Trilogy Metals Inc. 10-K

Item 2. PROPERTIES Trilogy’s principal business is the exploration and development of the Upper Kobuk Mineral Projects located in the Ambler Mining District in Northwest Alaska, United States. The Upper Kobuk Mineral Projects are held by Ambler Metals LLC (“Ambler Metals”), a limited liability company owned equally by Trilogy and South32 Limited, and is comprised of the (i) Arctic Project, a development stage property, which contains a high-grade polymetallic volcanogenic massive sulfide deposit; and (ii) Bornite Project, an exploration stage property, which contains a carbonate-hosted copper deposit. Both projects are material to Trilogy and are described below under the headings “Arctic Project” and “Bornite Project”. Except as otherwise stated, the scientific and technical information relating to the Arctic Project contained in this Form 10-K is derived from the 2023 S-K 1300 report for the Arctic Project titled “Arctic Project S-K 1300 Technical Report Summary, Ambler Mining District, Alaska” dated November 30, 2022 prepared by Ausenco Engineering Canada Inc., Wood Canada Limited, SRK Consulting (Canada) Inc. and Brown and Caldwell, each of whom are not affiliated with Trilogy (“S-K 1300 Arctic Report”). Except as otherwise stated, the scientific and technical information relating to the Bornite Project contained in this Form 10-K is derived from the 2025 S-K 1300 report for Bornite titled “S-K 1300 Technical Report Summary on the Initial Assessment of the Bornite Project, Northwest Alaska, USA” dated November 30, 2024 prepared by Wood Canada Limited, SRK Consulting (Canada) Inc., Ausenco Engineering Canada ULC. and International Metallurgical & Environmental and Core Geoscience LLC, which are each unaffiliated with Trilogy (“S-K 1300 Bornite Report”). ​ ​ 26 Table of Contents ​ ​ ​ ​ ​ 27 Table of Contents Mineral Resource Summary Table as of November 30, 2024 Project Resource Tonnage Average Grade Contained Metal Content Cu Pb Zn Au Ag Cu Pb Zn Au Ag Alaska Category (Mt) (%) (%) (%) (g/t) (g/t) (Mlb) (Mlb) (Mlb) (koz) (Moz) Arctic – 50% Attributable Interest Inferred 2.25 1.92 0.70 2.93 0.43 35.6 94.5 34.5 144 31 2.5 Bornite – 50% Attributable Interest Inferred 104.45 1.42 ​ ​ ​ ​ 3,263.5 ​ ​ ​ ​ Notes: 1. A Qualified Person and an employee of the Company, has approved the mineral reserves and mineral resources included in this Annual Report on Form 10-K as of November 30, 2024 and reviewed the resources and material assumptions in the S-K 1300 Arctic Report and the S-K 1300 Bornite Report and confirmed that the resources and material assumptions remain current as of November 30, 2024. 2. Mineral Resources were prepared in accordance with the standards and definitions of S-K 1300 and represent disclosure of Mineral Resources under S-K 1300 standards and definitions. 3. The Mineral Resource estimate is reported exclusive of Mineral Reserves. There are no Mineral Reserves estimated on the Bornite property. 4. Trilogy Metals’ 50% attributable interest is stated in the table. 5. Figures may not sum due to rounding. 6. The mineral resources are reported in place (point of reference). Arctic Notes: 7. Mineral Resources stated are contained within a conceptual pit shell developed using metal prices of $3.00/lb Cu, $0.90/lb Pb, $1.00/lb Zn, $1,300/oz Au and $18/oz Ag and metallurgical recoveries of 92% Cu, 77% Pb, 88% Zn, 63% Au and 56% Ag and operating costs of $3/t mining and $35/t process and general and administrative costs. The assumed average pit slope angle is 43º. The commodity pricing used a combination of two year trialing actual metal prices, and market research and bank analyst forward price projections, prepared in June 2020. 8. As a result of flattening the north end of the reserve pit to stabilize the pit wall due to the presence of talc, a portion of the reserve pit extended beyond the resource constraining pit shell and a second pass of mineral resource tabulation was performed exterior to the constraining resource pit and interior to the constraining reserve pit which is included in the Mineral Resource tabulation. 9. The cut-off grade is 0.5% copper equivalent: CuEq = (Cu% x 0.92) + (Zn% x 0.290) + (Pb% x 0.231) + (Au g/t x 0.398) + (Ag g/t x 0.005). Bornite Notes: 10. Mineral resources are constrained by: an open pit shell at a cut-off grade of 0.5% Cu, with an average pit slope of 43 degrees; and underground mining shapes assuming cut-and-fill mining method based on a 1.79% Cu grade shell for Ruby Zone and an optimized underground mineable stope shape assuming sublevel stoping mine method based on a break-even cut-off grade of 1.45% for South Reef. The cut-off grades assume a $4.60/lb Cu price, process recovery of 90.47%, process cost of $21.00/t processed, treatment, refining, sales cost of $0.78/lb Cu in concentrate, road use cost of $8.04/t processed, and 2% NSR royalty. For the open pit, costs include mining costs of $3.34/t mined and G&A cost of $4.30/t processed. For mining at South Reef, costs include mining costs of $65.00/t mined and G&A cost of $14.50/t processed. For mining at Ruby Zone, costs include mining costs of $90.00/t mined and G&A cost of $14.50/t processed. The long-term metal price forecast used a combination of information derived from 22 financial institutions, from pricing used in technical reports filed with Canadian regulatory authorities over the previous 12-month period from the effective date of the mineral resource estimate, from pricing reported by major mining companies in public filings such as annual reports, historical average pricing. ​ 28 Table of Contents Mineral Reserve Estimate as of November 30, 2024 for the Arctic Project, Alaska USA Classification Tonnage Average Grade Mt Cu (%) Pb (%) Zn (%) Au (g/t) Ag (g/t) Probable Mineral Reserves – 50% Attributable Interest 23.35 2.11 0.56 2.90 0.42 31.8 Notes: 1. A Qualified Person and an employee of the Company, has approved the mineral reserves and mineral resources included in this Annual Report on Form 10-K as of November 30, 2024 and reviewed the reserves and the material assumptions in the S-K 1300 Arctic Report and confirmed that the reserves and material assumptions remain current as of November 30, 2024. 2. Mineral Reserves were estimated assuming open pit mining methods and include a combination of internal and contact dilution. Total dilution is expected to be between 30% and 40%. Pit slopes vary by sector and range from 26° to 56°. A marginal NSR cut-off of $38.8 /t is used. 3. Mineral Reserves are based on prices of $3.46/lb Cu, $0.91/lb Pb, $1.12/lb Zn, $1,615/oz Au, and $21.17/oz Ag. T he long-term metal price forecast used a combination of information derived from 22 financial institutions, from pricing used in technical reports filed with Canadian regulatory authorities over the previous 12-month period prior to the publication of the S-K 1300 Arctic report, from pricing reported by major mining companies in public filings such as annual reports in the previous 12-month period prior to the publication of the S-K 1300 Arctic report, spot pricing, and three-year trailing average pricing. 4. Variable process recoveries averaging 92% Cu in Cu concentrate, 62% Pb in Pb concentrate, 88% Zn in Zn concentrate, 47% Au in Cu concentrate, 33% Ag in Cu concentrate, 26% Au in Pb concentrate and 49% Ag in Pb concentrate. 5. Mineral Reserves are based on mining cost of $2.52/t incremented at $0.02/t/5m and $0.012/t/5m below and above 790 m elevation, respectively. 6. Costs applied to processed material following: process operating cost of $18.31/t, G&A of $5.83/t, sustaining capital cost of $2.37/t, closure cost of $4.27/t, road toll cost of $8.04/t. 7. Strip ratio (waste:ore) is 7.3:1. 8. Selling terms following: payables of 96.5% of Cu, 95% of Pb and 85% of Zn, treatment costs of $80/t Cu concentrate, $160/t Pb concentrate and $215/t Zn concentrate; refining costs of $0.08/lb Cu in Cu concentrate, and$10/oz Au, $1.25/oz Ag in Pb concentrate; and transport cost $270.98/t concentrate. 9. Fixed royalty percentage of 1% NSR. 10. Trilogy Metals’ 50% attributable interest is stated in the table. 11. The point of reference for the Mineral Reserves is defined at the point where the ore is delivered to the processing plant. 12. The metal prices and costs were fixed over the 13-year mine life. The following descriptions summarize selected information about the Upper Kobuk Mineral Projects, which are located in the Ambler Mining District of Alaska and include the Arctic Project and the Bornite Project. The Arctic Project and the Bornite Project are held by Ambler Metals, of which Trilogy holds a 50% interest. All mineral resources and mineral reserve estimates with respect to the Arctic Project and Bornite Project that are disclosed in this Annual Report on Form 10-K are reported on a 100% basis unless otherwise noted. Please also see “ Management’s Discussion and Analysis—Project Activities ” for more information on the development and nature of our interest in the Upper Kobuk Mineral Projects. The Company’s book value of its investment in Ambler Metals is $107.5 million as of November 30, 2024. Arctic Project The Company is subject to and required to disclose mineral resources and mineral reserves in accordance with Subpart 229.1300 of Regulation S-K – Disclosure by Registrants Engaged in Mining Operations (“S-K 1300”). While the S-K 1300 rules are similar to National Instrument 43-101 Standards of Disclosure for Mineral Projects (“NI 43-101”) rules in Canada, they are not identical and therefore two reports have been produced for the Arctic Project. The information in Item 2, Properties, contains pertinent information required under both NI 43-101 and S-K 1300. 29 Table of Contents Except as otherwise stated, the scientific and technical information relating to the Arctic Project contained in this Form 10-K is derived from the (i) 2023 S-K 1300 report for the Arctic Project titled “Arctic Project S-K 1300 Technical Report Summary, Ambler Mining District, Alaska” dated November 30, 2022 prepared by Ausenco Engineering Canada Inc., Wood Canada Limited, SRK Consulting (Canada) Inc. and Brown and Caldwell, each of whom are not affiliated with Trilogy (“S-K 1300 Arctic Report”) and the (ii) 2023 Arctic Report titled “Arctic Project NI 43-101 Technical Report on Feasibility Study, Ambler Mining District, Alaska” with an effective date of January 20, 2023, prepared by Ausenco Engineering Canada Inc., Wood Canada Limited, SRK Consulting (Canada) Inc. and Brown and Caldwell (“NI 43-101 Arctic Report”). The information regarding the Arctic Project is based on assumptions, qualifications and procedures which are not fully described herein. Reference should be made to the full text of the S-K 1300 Arctic Report and the NI 43-101 Arctic Report which has been filed, as applicable, with the relevant US and Canadian securities regulatory authorities. The NI 43-101 Arctic Report is available for review on SEDAR+ at www.sedarplus.ca and the S-K 1300 Arctic Report is available for review on EDGAR at www.sec.gov. Arctic Project Description, Location and Access Project Description NovaGold acquired the Arctic Project from Kennecott Exploration Company and Kennecott Arctic Company (collectively, “Kennecott”) in 2004. In 2011, NovaGold transferred all copper projects to NovaCopper Inc. and spun-out NovaCopper to its then existing shareholders in 2012. NovaCopper Inc. subsequently underwent a name change to Trilogy Metals Inc. in 2016. Under the Kennecott Purchase and Termination Agreement, Kennecott retained a 1% net smelter return (“NSR”) royalty that was subsequently sold by Kennecott. The 1% NSR runs with the lands and is purchasable at any time from the royalty holder for a one-time payment of $10 million. The Arctic Project is directly held by Ambler Metals LLC (“Amber Metals”), in a 50/50 joint venture formed between South32 and Trilogy in February 2020. Upon the formation of the joint venture, Trilogy contributed all of its Alaskan assets, including the Arctic Project and the NANA Agreement, to Ambler Metals in exchange for a 50% membership interest and at the same time, South32 contributed $145 million in cash for a 50% membership interest. The land tenure consists of 2,136 contiguous State claims totaling 230,736 acres (93,336 hectares), including 905 40-acre claims, 1231 160-acre claims, and 18 Federal patented claims comprising 271.9 acres (110 hectares) held in the name of Ambler Metals. Surface use of the private land held as Federal patented claims is limited only by reservations in the patents and by generally-applicable environmental laws. Surface use of State claims allows the owner of the mining claim to make such use of the surface as is “necessary for prospecting for, extraction of, or basic processing of minerals.” NANA controls lands granted under the Alaska Native Claims Settlement Act to the south of the Arctic Project boundary. Ambler Metals and NANA are parties to the NANA Agreement that consolidates the parties’ land holdings into an approximately 190,929 hectares land package and provides a framework for the exploration and development of the area. The NANA Agreement has a term of 20 years, with an option in favour of Ambler Metals to extend the term for an additional 10 years. If, following receipt of a feasibility study and the release for public comment of a related draft environmental impact statement, a decision is made to proceed with construction of a mine on the lands subject to the NANA Agreement, NANA will have 120 days to elect to either (a) exercise a non-transferrable back-in-right to acquire between 16% and 25% (as specified by NANA) of that specific project; or (b) not exercise its back-in-right, and instead receive a net proceeds royalty equal to 15% of the net proceeds realized from such project. In the event that NANA elects to exercise its back-in-right, the parties will, as soon as reasonably practicable, form a joint venture with NANA electing to participate between 16% to 25%, and Ambler Metals owning the balance of the interest in the joint venture. If Ambler Metals decides to proceed with construction of a mine on its own lands subject to the NANA Agreement, NANA will enter into a surface use agreement which will afford Ambler Metals access to the Arctic Project along routes approved by NANA. In consideration for the grant of such surface use rights, NANA will receive a 1% net smelter royalty on production and provide an annual payment on a per acre basis. ​ 30 Table of Contents Location and Access The Arctic Project is located in the Ambler Mining District of the southern Brooks Range, in the Northwest Arctic Borough (“NWAB”) of Alaska. The Arctic Project is geographically isolated with no current road access or nearby power infrastructure. The Arctic Project is about 270 km east of the town of Kotzebue, 37 km northeast of the village of Kobuk, and 260 km west of the Dalton Highway, an all-weather State maintained public road, at geographic coordinates N67.17° latitude and W156.39° longitude and Universal Transverse Mercator (UTM) North American Datum (NAD) 83, Zone 4 coordinates 7453080N, 613110E. Primary access to the Arctic Project is by air, using both fixed wing aircraft and helicopters. There are four well-maintained, approximately 1,500 m-long gravel airstrips located near the Arctic Project, capable of accommodating charter fixed wing aircraft. These airstrips are located 64 km west at Ambler, 46 km southwest at Shungnak, 37 km southwest at Kobuk, and 34 km southwest at Dahl Creek. There is daily commercial air service from Kotzebue to the village of Kobuk, the closest community to the Arctic Project. During the summer months, the Dahl Creek Camp airstrip is suitable for larger aircraft, such as a C-130 and DC-6. In addition to the four 1,500 m airstrips, there is a 700 m airstrip located at the Bornite Camp. The airstrip at Bornite is suited to smaller aircraft, which support the Bornite Camp with personnel and supplies. There is also a 450 m airstrip (Arctic airstrip) located at the base of Arctic Ridge that can support smaller aircraft. A winter trail and a one-lane dirt track suitable for high-clearance vehicles or construction equipment links the Arctic Project’s main camp located at Bornite to the Dahl Creek airstrip southwest of the Arctic deposit. An unimproved gravel track connects the Arctic airstrip with the Arctic deposit. History Prospectors in search of gold, travelling up the Kobuk River in 1898-99 (Grinnell, 1901), found small gold placer deposits in the southern Cosmos Hills, south of the Arctic deposit, which were worked intermittently over the ensuing decades. Around this time, copper mineralization at Ruby Creek and Pardner Hill in the northern Cosmos Hills was explored using small shafts and adits (Smith and Eakin, 1911). In 1947, Rhinehart “Rhiny” Berg staked claims over the Ruby Creek prospects, carried out extensive trenching and the first diamond drilling, and constructed an airstrip for access (alaskamininghalloffame.org 2012). Bear Creek Mining Company (“BCMC”), an exploration subsidiary of Kennecott, optioned the Ruby Creek property from Berg in 1957. The prospect became known as Bornite and Kennecott conducted extensive exploration over the next 31 Table of Contents decade, culminating in the discovery of the high-grade No. 1 zone and the sinking of an exploration shaft to conduct underground drilling. While exploring the Bornite deposit, BCMC carried out reconnaissance exploration throughout the western Brooks Range, including a large regional stream sediment survey in 1962. Initial follow up did not identify mineralization of interest however in 1965, Riz Bigelow (BCMC) and his team of geologists found boulders of massive sulphides at an anomaly (1400 ppm Cu) located 28 km northeast of Bornite that led to the discovery of outcropping mineralization the following year. The area was subsequently staked and, in 1967, nine core holes were drilled at the Arctic deposit, eight of which yielded massive sulphide intercepts over an almost 500-m strike length. BCMC conducted intensive exploration on the property until 1977 and then intermittently through to 1998. No drilling or additional exploration was conducted on the Arctic Project between 1999 and 2003. In addition to drilling and exploration at the Arctic deposit, BCMC also conducted exploration at numerous other prospects in the Ambler Mining District (most notably Dead Creek, Sunshine, Cliff, and Horse). The abundance of VMS prospects in the district resulted in a series of competing companies in the area, including Sunshine Mining Company, Anaconda Company, Noranda Exploration Company, GCO Minerals Company, Cominco American Resource Inc. (Cominco), Teck Cominco, Resource Associates of Alaska, Watts, Griffis and McOuat Ltd., and Houston Oil and Minerals Company, culminating into a claim staking war in the district in 1973. Falconbridge and Union Carbide also conducted work later in the district. District exploration by Sunshine Mining Company and Anaconda resulted in two additional significant discoveries in the district; the Sun deposit located 60 km east of the Arctic deposit, and the Smucker deposit located 36 km west of the Arctic deposit. These two deposits are outside the current Arctic Project area. District exploration continued until the early 1980s on the four larger deposits in the district (Arctic, Bornite, Smucker and Sun) when the district fell into a hiatus due to depressed metal prices. In 1987, Cominco acquired the claims covering the Sun and Smucker deposits from Anaconda. Teck Resources Limited, as Cominco’s successor company, continues to hold the Smucker deposit. In 2007, Andover Mining Corporation purchased a 100% interest in the Sun deposit for $13 million and explored the property through 2013. The Sun deposit and adjacent lands were acquired by Valhalla Metals Inc., a private company, which staked over the Sun deposit in 2017 after the creditors for the bankrupt Andover Mining Corporation failed to pay the annual rent of the state claims and submit the Annual Labour Statement. In 1981 and 1983, Kennecott received three US Mineral Survey patents (MS2245 totaling 240 acres over the Arctic deposit – later amended to include another 32 acres; and MS2233 and MS2234 for 25 claims totaling 516.5 acres at Bornite). The Bornite patented claims and surface development were subsequently sold to NANA Regional Corporation, Inc. in 1986. No production has occurred at the Arctic deposit or at any of the other deposits within the Ambler Mining District. Prior Ownership and Ownership Changes – Arctic Deposit and the Ambler Lands BCMC initially staked federal mining claims covering the Arctic deposit area beginning in 1966. The 1960’s drill programs defined a significant high-grade polymetallic resource at the Arctic deposit and, in the early 1970s, Kennecott began the patent process to obtain complete legal title to the Arctic deposit. In 1981, Kennecott received US Mineral Survey patent M2245 covering 16 mining claims totaling 240.018 acres. In 1983, US Mineral Survey patent M2245 was amended to include two additional claims totaling 31.91 acres. With the passage of the Alaska National Interest Lands Conservation Act in 1980, which expedited native land claims outlined in the ANSCA and State lands claims under the Alaska Statehood Act, both the State of Alaska and NANA selected significant areas of land within the Ambler Mining District. State selections covered much of the Ambler schist belt, host 32 Table of Contents to the volcanogenic massive sulphide deposits including the Arctic deposit, while NANA selected significant portions of the Ambler Lowlands to the immediate south of the Arctic deposit as well as much of the Cosmos Hills including the area immediately around Bornite. In 1995, Kennecott renewed exploration in the Ambler schist belt containing the Arctic deposit patented claims by staking an additional 48 state claims at Nora and 15 state claims at Sunshine Creek. In the fall of 1997, Kennecott staked 2,035 state claims in the belt consolidating their entire land position and acquiring the majority of the remaining prospective terrain in the VMS belt. Five more claims were subsequently added in 1998. After a short period of exploration which focused on geophysics and geochemistry combined with limited drilling, exploration work on the Arctic Project again entered a hiatus. On March 22, 2004, Alaska Gold Company (“Alaska Gold”), a wholly-owned subsidiary of NovaGold completed an Exploration and Option Agreement with Kennecott to earn an interest in the Ambler land holdings. Previous Exploration and Development Results – Arctic Deposit Kennecott’s ownership of the Arctic Project saw two periods of intensive work from 1965 to 1985 and from 1993 to 1998, before optioning the property to NovaGold in 2004. Though reports, memos, and files exist in Kennecott’s Salt Lake City office, only limited digital compilation of the data exists for the earliest generation of exploration at the Arctic deposit and within the VMS belt. Beginning in 1993, Kennecott initiated a re-evaluation of the Arctic deposit and assembled a computer database of previous work at the Arctic deposit and in the district. A computer-generated block model was constructed in 1995 and an updated resource estimate was performed using the block model. Subsequently, Kennecott staked a total of 2,035 State of Alaska claims in 1997 and, in 1998 undertook the first field program since 1985. Due to the number of companies and the patchwork exploration that occurred as a result of the 1973 staking war, much of the earliest exploration work on the Ambler Schist belt was lost during the post-1980 hiatus in district exploration. The following subsections outline the best documented data at the Arctic deposit as summarized in the 1998 Kennecott exploration report, including the assembled computer database; however, this outline is not considered to be either exhaustive or in-depth. In 1982, geologists with Kennecott, Anaconda and the State of Alaska published the definitive geologic map of the Ambler schist belt (Hitzman et al. 1982). The S-K 1300 Arctic Report and the NI 43-101 Arctic Report both summarize the known exploration mapping, geochemical, and geophysical programs conducted for VMS targets in the Ambler Mining District. Table 1 below summarizes the exploration mapping, geochemical, geophysical, and mining studies conducted on the Arctic deposit. Geological Setting, Mineralization and Deposit Types Regional Geology – Southern Brooks Range The Ambler Mining District occurs along the southern margin of the Brooks Range within an east-west trending zone of Devonian to Jurassic age submarine volcanic and sedimentary rocks (Hitzman et al., 1986). The district covers both: 1) VMS-like deposits and prospects hosted in the Devonian age Ambler Sequence (or Ambler Schist belt or Schist Belt), a group of metamorphosed bimodal volcanic rocks with interbedded tuffaceous, graphitic and calcareous volcaniclastic metasediments; and 2) epigenetic carbonate-hosted copper deposits occurring in Silurian to Devonian age carbonate and phyllitic rocks of the Bornite Carbonate Sequence. The Ambler Sequence occurs in the upper part of the Anirak Schist, the thickest member of the Schist belt or Coldfoot subterrane (Moore et al., 1994). VMS-like stratabound mineralization can be found along the entire 110 km strike length of the district. Immediately south of the Schist belt, in the Cosmos Hills, a time equivalent section of the Anirak Schist includes the approximately 1 km thick Bornite Carbonate 33 Table of Contents Sequence. Mineralization of both the VMS-like deposits of the Schist belt and the carbonate-hosted deposits of the Cosmos Hills has been dated at 375 to 387 Ma (Selby et al., 2009; McClelland et al., 2006). The Ambler Mining District is characterized by increasing metamorphic grade to the north, perpendicular to the strike of the east-west trending units. The district shows isoclinal folding in the northern portion and thrust faulting to south (Schmidt, 1983). The Devonian to Late Jurassic age Angayucham basalt and the Triassic to Jurassic age mafic volcanic rocks are in low-angle over thrust contact with various units of the Ambler Schist belt and Bornite Carbonate Sequence along the northern edge of the Ambler Lowlands. Ambler Sequence Geology Rocks that form the Ambler Sequence consist of a lithologically diverse sequence of lower Devonian age carbonate and siliciclastic strata with interlayered mafic lava flows and sills. The clastic strata, derived from terrigenous continental and volcanic sources, were deposited primarily by mass-gravity flow into the sub-wavebase environment of an extending marginal basin. The Ambler Sequence underwent two periods of intense, penetrative deformation. Sustained upper greenschist-facies metamorphism with coincident formation of a penetrative schistosity and isoclinal transposition of bedding marks the first deformation period. Pervasive similar-style folds on all scales deform the transposed bedding and schistosity, defining the subsequent event. At least two later non-penetrative compressional events deform these earlier fabrics. Observations of the structural and metamorphic history of the Ambler Mining District are consistent with current tectonic evolution models for the Schist belt, based on the work of others elsewhere in the southern Brooks Range (Gottschalk and Oldow, 1988; Till et al., 1988; Vogl et al., 2002). Arctic Deposit Geology Previous workers at the Arctic deposit (Russell 1995 and Schmidt 1983) describe three mineralized horizons: the Main Sulphide Horizon, the Upper South Horizon and the Warm Springs Horizon. The Main Sulphide Horizon was further subdivided into three zones: the southeast zone, the central zone and the northwest zone. Previous deposit modelling was grade-based resulting in numerous individual mineralized zones representing relatively thin sulphide horizons. Earlier work by Ambler Metals defined the Arctic deposit as two or more discrete horizons of sulphide mineralization contained in a complexly deformed isoclinal fold with an upright upper limb and an overturned lower limb hosting the main mineralization. Nearby drilling suggested that a third upright lower limb, likely occurs beneath the currently explored stratigraphy. Mineralization Mineralization occurs as stratiform semi-massive sulphide (“SMS”) to massive sulphide (“MS”) beds within primarily graphitic schists and fine-grained quartz mica schists. The sulfide beds average 4 m in thickness but vary from less than 1 m up to as much as 18 m in thickness. The sulfide mineralization occurs within eight modelled zones lying along the upper and lower limbs of the Arctic isoclinal anticline. The zones are all within an area of roughly 1 km 2 with mineralization extending to a depth of approximately 250 m below the surface. There are five zones of MS and SMS that occur at specific pseudo-stratigraphic levels which make up the bulk of the Mineral Resource estimate. The other three zones also occur at specific pseudo-stratigraphic levels, but are too discontinuous. Unlike more typical VMS deposits, mineralization is not characterized by steep metal zonation or massive pyritic zones. Mineralization dominantly consists of sheet-like zones of base metal sulfides with variable pyrite and only minor zonation, usually on a small scale. Mineralization is predominately coarse-grained sulphides comprising chalcopyrite, sphalerite, galena, tetrahedrite-tennantite, pyrite, arsenopyrite, and pyrrhotite. Sulphides occur as disseminated (<30%), semi-massive (30 to 50% sulphide) to massive (greater than 50% sulphide) layers. Trace amounts of electrum are also present. Gangue minerals 34 Table of Contents associated with the mineralized horizons include quartz, barite, white mica, chlorite, stilpnomelane, talc, calcite, dolomite and cymrite. Deposit Types The mineralization at the Arctic deposit and at several other known occurrences within the Ambler Sequence stratigraphy of the Ambler Mining District consists of Devonian age, polymetallic (zinc-copper-lead-silver-gold) VMS-like occurrences. Observations and interpretations at the Arctic deposit such as: 1) the tectonic setting with Devonian volcanism in an evolving continental rift; 2) the geologic setting with bimodal volcanic rocks including pillow basalts and felsic volcanic tuffs; 3) an alteration assemblage with well-defined magnesium-rich footwall alteration and sodium-rich hanging wall alteration; and 4) typical polymetallic base-metal mineralization with massive and semi-massive sulphides, are indicative of a VMS deposit that has undergone high strain and complex folding and faulting. A variety of VMS types have been well documented in the literature (Franklin et al., 2005), with the Ambler Schist belt deposits most like deposits associated with bimodal felsic dominant volcanism related to incipient rifting. However, the abundance of volcaniclastic rocks with argillaceous sedimentary rocks and the tabular nature of mineralization are considered by Piercey (2022) to be similar to felsic silicilastic VMS environments. Evidence exists for both exhalation and emplacement on the seafloor and replacement of rocks in the sub-seafloor, either via filling of void space or via dissolution of original rocks and replacement by new minerals (Piercey, 2022). For example, the presence of barite, attributed to the mixing of BaCl 2 (aq) from hydrothermal fluids with seawater sulphate (SO 4 (aq)) at the vent-seawater interface supports some of the mineralization at Arctic likely precipitated on the seafloor. In contrast, there is ample textural evidence of subseafloor replacement at Arctic, such as the presence of transitions from massive sulphides into selective replacement of interpreted permeable tuff beds in the hanging wall mudstones. The tonnage, grades, and stratigraphic setting of the Arctic deposit, and its broader tectonostratigraphic setting, are similar to other felsic siliclastic VMS environments globally. The deposit has strong similarities to deposits found the Finlayson Lake VMS district, Yukon, Bathurst district, New Brunswick, and some parts of the Iberian Pyrite Belt, Spain-Portugal (Piercey, 2022). A VMS model is considered applicable for use in exploration targeting in the Arctic Project area. Exploration Table 1 summarizes the exploration work conducted by NovaGold, Trilogy (formerly, NovaCopper) and Ambler Metals from 2004 to 2022. Field exploration was largely conducted during the period between 2004 to 2007 and 2021 to 2022 with associated engineering and characterization studies between 2008 and 2021. Table 1 - Summary of Overall Exploration Activities Targeting VMS Style Mineralization in the Ambler Sequence Stratigraphy and the Arctic Deposit ​ Work Completed Year Details Focus Geological Mapping - 2004 - Arctic deposit surface geology - 2005 - Ambler Sequence west of the Arctic deposit - 2006 - COU, Dead Creek, Sunshine, Red - 2015, 2016 SRK Geotechnical Structural Mapping 35 Table of Contents Work Completed Year Details Focus - 2016 - Arctic deposit surface geology - 2021 - Snow, Ambler, Nani, DH, Cliff, Sunshine, Dead Creek, BT, 98-9/Pipe, COU, SE Arctic, Nora - 2022 - Snow, Ambler, Nani, DH, Bud, Sunshine, Dead Creek, BT, 98-9/Pipe, COU, East Arctic, Nora, South Cliff, SK, Cynbad, Z, Tom Tom, Kogo/White Creek Geophysical Surveys SWIR Spectrometry 2004 2004 drill holes Alteration characterization TDEM 2005 2 loops Follow-up of Kennecott DIGHEM EM survey 2006 13 loops District targets 2007 6 loops Arctic extensions Downhole EM 2007 4 drill holes Arctic deposit VTEM Plus (Versatile Time Domain Electromagnetic) airborne helicopter geophysical 2019 400m line spacing with 200m infill with tie lines 4000m spacing Ambler Mining District and Cosmos Hills with infill over Arctic, Sunshine and Horse-Cliff ZTEM (Z-Axis Tipper Electromagnetic) airborne helicopter geophysical 2019 400m line spacing with tie lines 4000m spacing Ambler Mining District and Cosmos Hills with infill over Arctic, Sunshine and Horse-Cliff Geochemistry - 2005 - Stream silts – core area prospects - 2006 - Soils – core area prospects - - Stream silts – core area prospects - 2007 - Soils – Arctic deposit area - 2021 - Soils - VTEM 26-29, JA Creek, West Dead Creek, Dead Creek - 2022 - Soils - Sub Arctic Valley, South Cliff, VTEM 26-29, VTEM-41, VTEM-23 , East and West Sunshine, Tom Tom, Kogo/White Creek, SK, Cynbad, East Arctic, West Dead Creek, Dead 36 Table of Contents Work Completed Year Details Focus Creek, 98-9/Pipe, Z, Nora, Ambler, Nani - Streams silts - Core area prospects Survey Collar 2004 to 2011, 2018, 2019, 2021, 2022 DGPS All 2004 to 2019 NovaCopper drill holes 2004, 2008 Resurveys Historical Kennecott drill holes Photography/Topography 2010 - Photography/topography LiDAR Survey 2015, 2016 - LiDAR over Arctic Deposit Technical Studies Geotechnical 2010 BGC Preliminary geotechnical and hazards ML/ARD 2011 SRK Preliminary ML and ARD Metallurgy 2012 SGS Preliminary mineralogy and metallurgy Geotechnical and Hydrology 2012 BGC Preliminary rock mechanics and hydrology Geotechnical and Hydrology 2015, 2016, 2018, 2019, 2021, 2022 SRK Arctic PFS and FS slope design ML/ARD 2015, 2016, 2017, 2018, 2019 SRK Static kinetic tests and ABA update - ongoing Metallurgy 2015, 2016, 2017, 2018, 2019, 2021 SGS, ALS Cu-Pb Separation Testwork; Flotation and Variability Testwork; SAG Mill Comminution (SMC) Testwork, filtration Testwork, thickener Testwork, and tailings settling testing Project Evaluation Resource Estimation 2008 SRK Resource estimation PEA 2011 SRK PEA - Underground 2012 Tetra Tech PEA – Open Pit PFS 2018 Ausenco Pre-Feasibility Study FS 2020 Ausenco Feasibility Study 37 Table of Contents Note: SWIR = short wave infrared; LiDAR = light detection and ranging; ML = metal leaching; BGC = BGC Engineering Inc.; SGS = SGS Canada; ALS = ALS Metallurgy; PEA = preliminary economic assessment. Drilling Drilling at the Arctic deposit and within the Ambler Mining District has been ongoing since the initial discovery of mineralization in 1966. Approximately 67,639 m of drilling has been completed within the Ambler Mining District, including 55,038 m of drilling in 285 drill holes at the Arctic deposit or on potential extensions in 32 campaigns spanning 56 years. All drill holes, except 11 geotechnical holes in 2017, 24 geotechnical holes drilled in 2018, 8 geotechnical holes from the 2021 program and 34 exploration holes from the 2022 program, for which assay results were not available - were considered for use in the estimate of Mineral Resources. Geotechnical drilling is summarized in Table 2 and Table 3. The number of holes reported for each year are the holes that were staffed by a geotechnician at the rig and the primary purpose was to gather geotechnical data. Table 2 – Summary of Geotechnical Drilling 2011 2015 2016 2017 2018 2019 2021 2022 Number of Holes 5 2 3 11 24 4 8 5 Oriented core X X X ​ ​ X X X Water level monitoring X X X X X X X X Falling head packer tests X ​ ​ ​ ​ ​ ​ ​ Point load tests X X X ​ ​ X X X Uniaxial compressive strength ​ X X ​ ​ X ​ ​ Direct shear testing ​ X X ​ ​ X X X Modulus testing ​ X X ​ ​ X ​ ​ Triaxial testing ​ X X ​ ​ X X X Acoustic Televiewer ​ ​ X ​ ​ ​ ​ ​ Falling Head, Singleor Straddle packer tests X ​ X ​ ​ ​ ​ ​ Airlift pump test ​ ​ X ​ ​ ​ ​ ​ Hydraulic conductivity testing (slug testing) ​ ​ ​ X ​ ​ ​ ​ Cohesive and residual shear strength tests on soils ​ ​ ​ X X ​ ​ ​ Compressive strength test on core and rock ​ ​ ​ X X ​ ​ ​ Extended duration injection tests ​ ​ ​ ​ ​ X ​ ​ ​ 38 Table of Contents Table 3 – Summary of Geotechnical Drilling by Year and Purposes Year Purpose 2011 Obtain geotechnical data in areas of the deposit that may host underground infrastructure or could pose issues with underground mining. 2015 Collect geotechnical and hydrological data to better understand the wall rock characteristics and hydrology within the open pit area. 2016 Complete the 3 drill holes that were deferred/not completed from the 2015 program. 2017 Collect geotechnical and hydrological data for tailings management and waste rock facilities within the entire Sub Arctic Creek valley. 2018 Collect geotechnical and hydrological data for waste rock dump, tailings management facility, and surface infrastructure in the Upper Sub Arctic Creek Valley. 2019 Provide additional geotechnical and hydrological data for pit design for the Feasibility Study. 2021 Define talc horizons on east side of pit for pit design. 2022 Define extent of lower talc horizons on northeast side of pit for pit design. ​ NovaGold re-surveyed collars of selected historical holes in 2004 and again in 2008. The re-surveys showed little variation compared to the historical surveys. The downhole survey data show a pronounced deviation of the drill holes toward an orientation more normal to the foliation. Incomplete Kennecott data exist with regards to overall core recovery but based on 917 intervals of 3.05 m or less in the historical database, the average recovery was 92%. Kennecott RQD measurements in the 1998 program averaged 87.0%. There has been no systematic evaluation of recovery by rock type. Core recovery during NovaGold/NovaCopper/Trilogy Metals and Ambler Metals drill programs was good to excellent, resulting in quality samples with little to no bias. Sampling, Analysis and Data Verification Sampling and Analysis The data for the Arctic deposit were generated over three primary drilling campaigns: 1966 to 1986 when BCMC, a subsidiary of Kennecott was the primary operator, 1998 when Kennecott resumed work after a long hiatus, and 2004 to present under NovaGold, Trilogy (formerly, NovaCopper), and Ambler Metals. Between 2004 and 2005, NovaGold conducted a systematic drill core re-logging and re-sampling campaign of Kennecott and BCMC era drill holes AR-09 to AR-74. NovaGold either took 1 to 2 m samples every 10 m or sampled entire lengths of previously unsampled core within a minimum of 1 m and a maximum or 3 m intervals. The objective of the sampling was to generate a full ICP geochemistry dataset for the Arctic deposit and ensure continuous sampling throughout the deposit. From 2004 to 2019, sample intervals are determined by the geological relationships observed in the core and limited to a 2.5 m maximum length and 1 m minimum length. Sample intervals terminate at lithological and mineralization boundaries. After logging, the core was cut in half using diamond core saws. If core was not competent, it was split by using a spoon to transfer half of the core into the sample bag. One-half of the core was returned to the core box for storage on site and the other half was bagged, labelled, and sent to ALS Minerals Laboratories in Vancouver for analysis and the other half was archived in the core storage facility at the Bornite Camp facilities or at the Ambler Metals warehouse in Fairbanks. For the 2021 metallurgical holes, ¼ core was sampled for analysis at ALS, ¼ retained, and ½ sent for metallurgical testing. 39 Table of Contents Samples were logged into a tracking system on arrival at ALS Minerals, and weighed. Samples were then crushed dried, and a 250 g split pulverized to greater than 85% passing 75 μm. Samples were submitted for multielement analysis of a 0.25 gram sample by Inductively Coupled Plasma (ICP) Mass Spectrometry (MS) following a 4-acid digestion, and for gold analysis of a 30 gram sample by Fire Assay (FA) with an Atomic Absorption (AA) finish. Over limit ICP-MS Cu, Pb, and Zn samples were resubmitted for analysis of a 0.4 gram sample by ICP-Atomic Emission Spectroscopy (AES) or AA following a 4 acid digestion. The overlimit value for Cu, Pb, and Zn is 10,000 ppm. Over limit gold results were resubmitted for analysis of a 30 gram sample by FA with a Gravimetric finish. The overlimit value for Au is 10 ppm. The Lower detection limits for Cu, Pb, and Zn by ICP-MS are 0.2 ppm, 0.5 ppm, and 2 ppm respectively. The lower detection limit for Au by FAAA is 0.05 ppm. Between 2004 and 2005 NovaGold completed a resampling program of historic drill holes. As a result, 85% of the assay intervals now have recent assay results from ALS Minerals. All core and pulp reject samples submitted to the ALS Minerals laboratory since 2004 were accompanied by standard, blank and duplicate control samples. Secondary laboratory check samples were analysed at Acme in Vancouver or SGS Burnaby. The secondary laboratory check samples were selected to represent the data population using a random selection of 5% of the samples within percentile range groups. GeoSpark Consulting has prepared several reports summarizing the control sample results received between 2004 and 2019. Paired laboratory and field determinations for mineralized zone SG measurements from 1998 and the 2004 program show very low variation. SRK conducts monthly QA/QC review of kinetic test leachates for all operating kinetic tests. Data Verification Wood qualified persons reviewed database verification and laboratory QA/QC reports and made data entry error spot checks, inspected down hole survey results for anomalous kinks and excessive bends in the drill hole traces, reviewed reports summarizing the results of drill core sampling and assaying completed since 2004, reviewed the assay database for gaps and overlaps, and reviewed the historic re-assay program results. The following two significant issues were observed: ● A significant high bias in historic Cu and low bias in historic Pb assay results ● Apparent low bias in Random Forest assisted specific gravity predictions In the current assay table historic sample interval assay results are given priority over the historic sample interval re-assay results. This is not expected to have a material impact on the grade estimation but using the re-assay results would further mitigate the risk associated with the observed biases in the historic Cu and Pb values. Overall, the database verification and management and the laboratory QAQC monitoring completed by NovaGold, Trilogy Metals, and Ambler Metals has resulted in a reasonably reliable drill hole database suitable for supporting the Mineral Resource estimated for the Arctic deposit. Some deficiencies exist that when rectified will make the drill hole database even more robust. Mineral Processing and Metallurgical Testing Since 1970, metallurgical testwork has been conducted to evaluate the ability of the Arctic deposit to produce copper, lead and zinc concentrates. In general, the samples tested produced similar metallurgical performances and the Arctic Project has seen the development of a robust metal recovery process to support the current operational plans. Work 40 Table of Contents conducted included mineralogy and flotation testing, locked cycle tests, comminution tests, copper/lead separation testwork, talc optimization testwork, and thickening and filtration testing. Testwork can be broken into four key time periods: 1. Historical testwork completed prior to 2012, primarily by Kennecott Research Centre in Utah, and Lakefield Research Ltd., Lakefield, Ontario; 2. Preliminary Trilogy testwork conducted at SGS Mineral Services, Burnaby (“SGS Burnaby”), in 2012 to 2015; 3. Detailed Trilogy testwork conducted at ALS Metallurgy in Kamloops, BC (“ALS Metallurgy”) in 2015 to 2019; and 4. Amber Metals testwork conducted at ALS Metallurgy and SGS Mineral Services in 2021 to 2022. In 2012, SGS Burnaby conducted a metallurgical test program to further study metallurgical responses of the samples produced from Zones 1, 2, 3, and 5 of the Arctic deposit. The flotation test procedures used talc pre-flotation, conventional copper-lead bulk flotation and zinc flotation, followed by copper and lead separation. In general, the 2012-2015 test results indicated that the samples responded well to the flowsheet tested. The average results of the locked cycle tests (without copper and lead separation) were as follows: ● The copper recoveries to the bulk copper-lead concentrates ranged from 89% to 93% excluding the Zone 1 & 2 composite which produced a copper recovery of approximately 84%; the copper grades of the bulk concentrates were 24% to 28%. ● Approximately 92% to 94% of the lead was recovered to the bulk copper-lead concentrates containing 9% to 13% lead. ● The zinc recovery was 84.2% from Composite Zone 1 & 2, 93.0% from Composite Zone 3 and 90.5% from Composite Zone 5. On average, the zinc grades of the concentrates produced were higher than 55%, excluding the concentrate generated from Composite Zone 1 & 2, which contained only 44.5% zinc. ● Gold and silver were predominantly recovered into the bulk copper-lead concentrates. Gold recoveries to this concentrate ranged from 65% to 80%, and silver recoveries ranged from 80% to 86%. Using an open circuit procedure, the copper and lead separation tests on the bulk copper–lead concentrate produced from the locked cycle tests generated reasonable copper and lead separation. The copper concentrates produced contained approximately 28% to 31% copper, while the grades of the lead concentrates were in the range of 41% to 67% lead. In this testwork program, it appeared that most of the gold reported to the copper concentrate and on average the silver was equally recovered into the copper and lead concentrates. Subsequent testwork to better define the copper and lead separation process was conducted in 2017, including a more detailed evaluation of the precious metal deportment in the copper and lead separation process. Grindability testing was completed during both the SGS Burnaby and ALS Metallurgy testwork programs to support the design and economics of efficient grinding of the Arctic materials. SAG mill test results included a single JKTech drop-weight test and 19 SAG media competency tests using variability samples. Test results show the material is amenable to SAG milling and is relatively soft, with a reported breakage (axb) average value of 189.7. Bond ball mill work index (BWi) tests were completed on 44 samples and values ranged from 5.4 to 13.1 kWh/t with an average BWi of 8.82 kWh/t. Abrasion index (Ai) tests were completed on five samples and values fluctuated from 0.017 to 0.072 g for the measured samples. The data indicate that the samples are neither resistant nor abrasive to ball mill grinding. The materials are considered to be soft or very soft in terms of grinding requirements. The grinding testwork was used to support detailed grinding circuit design. 41 Table of Contents In 2017, ALS Metallurgy conducted detailed copper and lead separation flotation testwork using a bulk sample of copper– lead concentrate produced from the operation of a pilot plant. This testwork confirmed high lead recoveries in locked cycle testing of the copper–lead separation process and confirmed precious metal recoveries into the representative copper and lead concentrates. This testwork indicated a clear tendency of the gold values to follow the lead concentrate, giving it a significant gold grade and value. Detailed mineralogical analysis showed that a majority of gold values were occurring as liberated fine-grained gold particles. The conclusions of testwork conducted both in 2012 and 2017 indicate that the Arctic materials are well-suited to the production of high-quality copper and zinc concentrates using flotation techniques which are industry standard. Copper and zinc recovery data were reported in the range of 88% to 92%, which reflected the high-grade nature of the deposit as well as the coarse-grained nature of these minerals. Grade variations within the deposit will be observed as indicated by the grade variations observed in variability samples, however, mill feed variability is expected to be limited and readily manageable with good plant operational practices. Lead concentrates have the potential to be of good quality and can also be impacted by zones of very high talc. Considerable care will be required to ensure maximum talc recovery to remove talc, which has the potential to dilute lead concentrate grades. The lead concentrate is also shown to be rich in precious metals, which has some advantages in terms of marketability of this material. Ancillary testwork was completed by third party consultants on representative concentrate samples, to provide thickening and filtration data for the various concentrates. Settling and filtration rates were observed to be typical for sulfide concentrates and moisture contents in final filter cakes were observed to be lower than expected. Metallurgical testwork was completed to provide representative tailings samples for use in detailed solids settling and compaction testwork to provide data for tailings design studies. A detailed study of water treatment chemistry was undertaken to evaluate and confirm the option of destroying cyanide contained in solutions from the proposed copper–lead separation process. The use of an SO2/air process in a small-scale pilot plant demonstrated removal of 99% of the contained cyanide and supported the concept of maintaining low cyanide concentrations within the proposed tailings pond solutions. In 2021, various metallurgical testwork programs were conducted at ALS Metallurgy, SGS, and MO Group. ALS Metallurgy completed several testwork programs, including flotation testing with the Preflotation circuit only to establish talc performance; further flowsheet development test work to investigate the benefits of sequential flotation versus the original bulk flow sheet; and a variability testwork to support the development of improved metallurgical recovery models. The objective of the ALS Metallurgy program was to investigate bulk and sequential flotation flowsheets with composites formed from two parent composites, and then select a flowsheet for a geo-metallurgical evaluation through testing with variability samples. The mineralization was amenable to either a bulk flowsheet followed by copper-lead separation, or a sequential flowsheet, both following a pre-flotation stage to remove talc. Table 4 shows average performance obtained for the Avg Talc Composite in the Flowsheet Development phase of the testing. 42 Table of Contents Table 4 – Comparison of Bulk versus Sequential Locked-Cycle Test Results – ALS 2021 ​ Composite Assays Distribution (%) Cu (%) Pb (%) Zn (%) Ag (g/t) Au (g/t) Mg (%) Cu Pb Zn Ag Au Avg Talc Bulk Copper concentrate 28.0 0.86 4.27 181 4.17 0.46 87.3 8.3 9.1 36.0 60.9 Lead concentrate 7.90 39.0 6.30 1124 4.75 1.23 5.1 78.1 2.8 46.0 14.3 Zinc concentrate 0.87 0.38 55.9 41 0.35 0.04 1.9 2.6 83.3 5.7 3.5 Avg Talc - Sequential Copper concentrate 27.6 0.87 2.05 168 3.23 1.96 90.2 8.9 4.7 34.9 48.7 Lead concentrate 2.72 49.3 9.71 1360 5.31 1.40 1.2 69.9 3.1 39.4 11.2 Zinc concentrate 0.98 1.09 54.5 47 0.77 0.17 2.1 7.3 83.5 6.5 7.7 ​ Copper recovery to the copper concentrate was slightly higher for the sequential flowsheet; however, gold recovery to the copper concentrate was substantially lower. The lead concentrate grade for the Avg Talc composite could likely be improved over that shown above with optimization of copper-lead separation conditions given the higher lead concentrate grade measured with other composites. Zinc circuit performance was similar for the two flowsheets, although higher zinc recovery to the copper concentrate was recorded for the bulk circuit. Magnesium content in the copper concentrate was higher for the sequential circuit, but similar in the lead concentrate for both circuits. Based on economic analysis comparing the bulk and sequential circuit, the bulk circuit flowsheet was selected for the Variability testing. An overall metallurgical balance for the project is summarized in Table 5. The projected metallurgical recoveries are based on an expected average recovery over the life-of-mine (LOM), and results of metallurgical variability testwork conducted in 2021 and 2022. 43 Table of Contents Table 5 – Summary of Overall Metal Recovery – Arctic Project Process stream Mass % Concentrate Grade Metal Recoveries Cu % Pb % Zn % Au g/t Ag g/t Cu % Pb % Zn % Au % Ag % Process Feed 100 2.1 0.5 2.8 0.4 31.1 - - - - - Copper Conc. 6.3 30.3 1.7 0.7 3.4 160.5 92.1 19.4 1.6 52.2 32.4 Lead Conc. 0.6 2.0 53.9 5.9 14.1 2425.8 0.6 61.3 1.3 21.4 48.8 Zinc Conc. 4.7 1.0 0.5 53.6 0.3 38.3 2.2 4.4 88.4 3.2 5.7 Tailings 88.4 0.1 0.1 0.3 0.1 4.6 5.1 14.8 8.7 23.2 13.1 ​ SGS conducted SAG Power Index (SPI®) tests to investigate the effect of friable ores on the plant throughput. MO Group conducted talc circuit modelling using the data obtained from the ALS Metallurgy Preflotation test work program to investigate the benefits of talc circuit open and closed-circuit cleaning. The MO Group also conducted dewatering and filtration test work on the talc concentrate and final tailings generated from the Preflotation test work program. Thickening and filtration testwork were completed by the MO Group on representative preflotation concentrate and tailings samples, to investigate opportunities to improve water recovery and reduce operating costs. The results were used to incorporate a tailings thickener in the process plant flow sheet. Mineral Resource and Mineral Reserve Estimates Mineral Resource Estimate Mineral Resources were first disclosed under S-K 1300 standards for the fiscal year ended November 30, 2022 and definitions in a filing with the United States Securities and Exchange Commission (SEC). A description of the key assumptions, parameters, and methods used in the mineral resource estimate are included in Chapter 11 of the S-K 1300 Arctic Report . A brief discussion of the material assumptions and criteria used in the mineral resource estimation are as follows: Mineral resource estimates are performed from a 3D block model based on geostatistical applications using LeapFrog software. The block model has a parent block size measuring 10 x 10 x 5 m with a sub-block size measuring 2 x 2 x1 m and uses data derived from 171 drill holes within the Arctic deposit. The resource estimate was generated using drill hole sample assay results and the interpretation of a geological model which relates to the spatial distribution of copper, lead, zinc, gold and silver. Interpolation characteristics were defined based on the geology, drill hole spacing, and geostatistical analysis of the data. The effects of potentially anomalous high-grade sample data, composited to 2 m intervals, are controlled by capping each mineralization zone. The grade models have been validated using a combination of visual and statistical methods. The resources were classified according to their proximity to the sample data locations and are reported using the standards and definitions in S-K 1300 in the S-K 1300 Arctic Report. The tonnes, grade, and classification are the same under the two standards of S-K 1300 and CIM Definition Standards for Mineral Resources and Mineral Reserves (May 2014) for those estimates reported in this document. Model blocks estimated by three or more drill holes spaced at a maximum distance of 100 m are included in the Indicated category. Inferred blocks are within a maximum distance of 150 m from a drill hole. 44 Table of Contents The deposit is amenable to open pit extraction methods. Reasonable prospects for economic extraction were established by constraining mineralization within a pit shell based on technical and economic assumptions presented in Table 6. As a result of flattening the north end of the reserve pit to stabilize the pit wall due to the presence of talc, a portion of the reserve pit extended beyond the resource constraining pit shell. A second pass of resource tabulation was performed on the Indicated and Inferred classified blocks exterior to the resource constraining pit shell and interior to the reserve constraining pit shell, above a 0.5% copper equivalent (CuEq) cut-off. The formula for the CuEq is shown in footnote 5 of Table 7. Table 6 - Parameters Used to Generate a Resource-Constraining Pit Shell Optimization Parameter Unit Value Open Pit Mining Cost $/t mined 3 Milling Cost + G&A $/t processed 35 Pit Slope degree 43 Copper Price $/lb 3.00 Lead Price $/lb 0.90 Zinc Price $/lb 1.00 Gold Price $/oz 1,300 Silver Price $/oz 18 Metallurgical Recovery: Copper % 92 Lead % 77 Zinc % 88 Gold % 63 Silver % 56 Note: no adjustments for mining recovery or dilution. The metal prices and costs were fixed over the 13-year mine life. The metal prices are within the range of industry consensus of long-term average metal prices based on an assessment of industry peers, and long-term forecast prices by banks at the time of the mineral resource estimate. Trilogy’s attributable interest in the Mineral Resource estimate exclusive of Mineral Reserves is stated in Table 7a. The Mineral Resource estimate inclusive of Mineral Reserves is stated in Table 7b . All Indicated Mineral Resources have been converted to Mineral Reserves. Mineral Resources are reported in place (point of reference). The table below shows Mineral Resources on a 100% basis as well as Trilogy’s attributable interest of 50% of the tonnes and metal content. Table 7a – S-K 1300 Mineral Resource Summary Table, Exclusive of Mineral Reserves Resource Tonnage Average Grade Contained Metal Content Cu Pb Zn Au Ag Cu Pb Zn Au Ag Category (Mt) (%) (%) (%) (g/t) (g/t) (Mlb) (Mlb) (Mlb) (koz) (Moz) Inferred -100% 4.5 1.92 0.70 2.93 0.43 35.6 189 69 288 62 5 Inferred – 50% Attributable Interest 2.25 1.92 0.70 2.93 0.43 35.6 94.5 34.5 144 31 2.5 Notes: 45 Table of Contents 1. A Qualified Person and an employee of the Company, has approved the mineral resources included in this Annual Report on Form 10-K as of November 30, 2024 and reviewed the resources and material assumptions in the S-K 1300 Arctic Report and confirmed that the resources and material assumptions remain current as of November 30, 2024. 2. Mineral Resources were prepared in accordance with the standards and definitions of S-K 1300. 3. Mineral Resources stated are contained within a conceptual pit shell developed using metal prices of $3.00/lb Cu, $0.90/lb Pb, $1.00/lb Zn, $1,300/oz Au and $18/oz Ag and metallurgical recoveries of 92% Cu, 77% Pb, 88% Zn, 63% Au and 56% Ag and operating costs of $3/t mining and $35/t process and general and administrative costs. The assumed average pit slope angle is 43º. The commodity pricing used a combination of two year trailing actual metal prices, and market research and bank analyst forward price projections, prepared in June 2020. 4. As a result of flattening the north end of the reserve pit to stabilize the pit wall due to the presence of talc, a portion of the reserve pit extended beyond the resource constraining pit shell and a second pass of mineral resource tabulation was performed exterior to the constraining resource pit and interior to the constraining reserve pit which is included in the Mineral Resource tabulation. 5. The cut-off grade is 0.5% copper equivalent: CuEq = (Cu% x 0.92) + (Zn% x 0.290) + (Pb% x 0.231) + (Au g/t x 0.398) + (Ag g/t x 0.005). 6. The Mineral Resource estimate is reported exclusive of those Mineral Resources that were converted to Mineral Reserves. 7. Figures may not sum due to rounding. ​ Table 7b – NI 43-101 Mineral Resource Summary Table, Inclusive of Mineral Reserves Resource Tonnage Average Grade Contained Metal Content Cu Pb Zn Au Ag Cu Pb Zn Au Ag Confidence Category (Mt) (%) (%) (%) (g/t) (g/t) (Mlb) (Mlb) (Mlb) (koz) (Moz) Indicated 35.7 2.98 0.79 4.09 0.59 45.2 2,347 621 3,216 675 52 Inferred 4.5 1.92 0.70 2.93 0.43 35.6 189 69 288 62 5 Notes: 1. Mineral Resources are current as of November 30, 2022 and were verified by a Wood QP. 2. Mineral Resources stated are contained within a conceptual pit shell developed using metal prices of $3.00/lb Cu, $0.90/lb Pb, $1.00/lb Zn, $1300/oz Au and $18/oz Ag and metallurgical recoveries of 92% Cu, 77% Pb, 88% Zn, 63% Au and 56% Ag and operating costs of $3/t mining and $35/t process and G&A. The assumed average pit slope angle is 43°. 3. The cut-off grade is 0.5% copper equivalent. CuEq = (Cu%x0.92) + (Zn%x0.290) + (Pb%x0.231) + (Au g/tx0.398) + (Ag g/tx0.005). 4. As a result of flattening the north end of the reserve pit to stabilize the pit wall due to the presence of talc, a portion of the reserve pit extended beyond the resource constraining pit shell. Approximately 568kt of 1.72% Cu, 0.77% Pb, 0.23 g/t Au and 21.3 g/t Ag in the Indicated category, and approximately 319 kt of 2.01% Cu, 0.87% Pb, 2.53% Zn, 0.50 g/t Au and 37.5 g/t Ag in the Inferred category were added to the Mineral Resource tabulation. 5. The Mineral Resource estimate is reported inclusive of those Mineral Resources that were converted to Mineral Reserves. 6. Trilogy Metals’ attributable interest is 50% of the amounts in the table. 7. Figures may not sum due to rounding. Factors that may affect the mineral resource estimate are listed below: ● Uncertainties in sampling and drilling methods, data processing and handling. ● Metal price assumptions. ● Uncertainties in the cost assumptions used to determine the cut-off grade. ● Uncertainties in the geological and mineralization shapes, and geological and grade continuity assumptions. 46 Table of Contents ● Uncertainties in the historically predicted (estimated) SG values determined by Random Forest Regressor. ● Uncertainties in the geotechnical, mining, and metallurgical recovery assumptions. ● Uncertainties represented by historical assay values for payable metals. ● Uncertainties in the resource estimation parameters including parameters such as capping values, search ellipsoids, variogram models, number of composites. ● Changes in the Mineral Resource Classification criteria. ● Uncertainties to the input and design parameter assumptions that pertain to the conceptual pit constraining the estimates. ● Uncertainties in the assumptions made to the concentrate marketability, payability and penalty terms. ● Uncertainties in the assumptions regarding the continued ability to access the site, retain mineral and obtain surface rights titles, obtain environment and other regulatory permits, and maintain the social license to operate. Mineral Reserve Estimates Mineral Reserves were first disclosed under S-K 1300 standards for the fiscal year ended November 30, 2022 in a filing with the SEC. A description of the key assumptions, parameters, and methods used in the mineral reserve estimate are included in Chapter 12 of the S-K 1300 Arctic Report . A brief discussion of the material assumptions and criteria used in the mineral reserve estimation are as follows: Mineral Reserves were classified in accordance with the standards and definitions of S-K 1300 in the S-K 1300 Arctic Report. There are no differences in the resulting tonnes, grade, or classification between the two reporting standards of S-K 1300 and CIM Definition Standards for Mineral Resources and Mineral Reserves (May 2014) for those estimates reported in this document. Modifying factors were applied to the Indicated Mineral Resources to convert them to Probable Mineral Reserves. All of the Indicated Mineral Resources were converted to Probable Mineral Reserves. The point of reference for reporting the Mineral Reserves is at delivery to the mill, as such, the Mineral Reserves for the Arctic deposit incorporate appropriate mining dilution and mining recovery estimations. The pit shell that defines the ultimate pit limit was derived in Whittle using the Pseudoflow pit optimization algorithm. The optimization procedure uses the block value and pit slopes to determine a group of blocks representing pits of valid slopes that yield the maximum profit. The block value is calculated using information stored in the geological block model, commodity prices, mining and processing costs, process recovery, and the sales cost for the metals produced. The pit slopes are used as constraints for removal precedence of the blocks (Xiaoyu Bai, et al., 2017). Table 8 provides a summary of the primary optimization inputs. Metal prices and costs were fixed over the 13-year mine life . Table 8 – Optimization Inputs Parameter Unit Value Cu Conc. Pb Conc. Zn Conc. Metal Prices Copper $/lb 3.46 ​ ​ ​ Lead $/lb 0.91 ​ ​ ​ Zinc $/lb 1.12 ​ ​ ​ Gold $/oz 1,615 ​ ​ ​ 47 Table of Contents Parameter Unit Value Cu Conc. Pb Conc. Zn Conc. Silver $/oz 21.17 ​ ​ ​ Discount Rate % 8 ​ ​ ​ Dilution and Mine Losses % Estimated in a block-by-block basis, adding up 30% to 40%. Mining Cost Reference Bench Elevation m 790 ​ ​ ​ Base Cost $/t 2.52 ​ ​ ​ Incremental Mining Cost ​ ​ ​ ​ ​ Uphill (below 790m) $/t/5m 0.02 ​ ​ ​ Downhill (above 790m) $/t/5m 0.012 ​ ​ ​ Process Costs Operating Cost $/t milled 18.31 ​ ​ ​ G&A $/t milled 5.83 ​ ​ ​ Sustaining Capital $/t milled 2.37 ​ ​ ​ Road Toll Cost $/t milled 8.04 ​ ​ ​ Closure $/t milled 4.27 ​ ​ ​ Processing Rate kt/d 10 ​ ​ ​ Process Recovery Copper % ​ 89.9 2.4 2.7 Lead % ​ 8.1 79 2.2 Zinc % ​ 3.4 0.4 90.6 Gold % ​ 10.9 62.1 5.4 Silver % ​ 26.4 63.1 3.4 Payable – Main Element % ​ 96.5 95 85 Treatment Cost $/dmt ​ 80 160 215 Refining Cost Copper $/lb ​ 0.08 - - Gold $/oz ​ 5 10 - Silver $/oz ​ 0.5 1.25 - Transport Cost $/dmt 271 ​ ​ ​ Concentrate Losses % weight 0.42 ​ ​ ​ 48 Table of Contents Parameter Unit Value Cu Conc. Pb Conc. Zn Conc. Insurance Cost % 0.15 ​ ​ ​ Representation/Marketing $/wmt 2.5 ​ ​ ​ Slope Angles Geotechnical Sector 1 (2L-E) degrees Variable based on slope dip direction. IRA ranging from 26 to 56. Geotechnical Sector 2 (2L-W) degrees Variable based on slope dip direction IRA ranging from 38 to 56. Geotechnical Sector 3 (2U) degrees Variable based on slope dip direction IRA ranging from 29 to 56. Geotechnical Sector 4 (3) degrees Variable based on slope dip direction IRA ranging from 30 to 56. Geotechnical Sector 5 (4L) degrees Variable based on slope dip direction IRA ranging from 34 to 56. Geotechnical Sector 6 (4U) degrees Variable based on slope dip direction IRA ranging from 37 to 56. Royalties NANA Surface Use %NSR 1 ​ ​ ​ Note: IRA = inter ramp angle The Mineral Reserves statement is shown in Table 9. The table below shows Mineral Resources on a 100% basis as well as Trilogy’s attributable interest of 50% of the tonnes and metal content. Table 9 – Mineral Reserve Estimate Confidence Category Tonnage Average Grades Mt Cu (%) Pb (%) Zn (%) Au (g/t) Ag (g/t) Probable Mineral Reserves – 100% 46.7 2.11 0.56 2.90 0.42 31.8 Probable Mineral Reserves – 50% Attributable Interest ​ 23.35 2.11 0.56 2.90 0.42 31.8 Notes: 1. A Qualified Person and an employee of the Company, has reviewed the reserves and material assumptions in the S-K 1300 Arctic Report and confirmed that the reserves and the material assumptions remain current as of November 30, 2024. 2. Mineral Reserves were estimated assuming open pit mining methods and include a combination of internal and contact dilution. Total dilution is expected to be between 30% and 40%. Pit slopes vary by sector and range from 26° to 56°. A marginal NSR cut-off of $38.8/t is used. 3. Mineral Reserves are based on prices of $3.46/lb Cu, $0.91/lb Pb, $1.12/lb Zn, $1,615/oz Au, and $21.17/oz Ag. T he long-term metal price forecast used a combination of information derived from 22 financial institutions, from pricing used in technical reports filed with Canadian regulatory authorities over the previous 12-month period prior to the publication of the S-K 1300 Arctic report, from pricing reported by major mining companies in public filings such as annual reports in the previous 12-month period prior to the publication of the S-K 1300 Arctic report, spot pricing, and three-year trailing average pricing. 4. Variable process recoveries averaging 92.2% Cu in Cu concentrate, 62.2% Pb in Pb concentrate, 87.6% Zn in Zn concentrate, 16.0% Pb in Cu concentrate, 1.9% Zn in Cu concentrate, 47.2% Au in Cu concentrate, 32.7% Ag in Cu concentrate, 0.8% Cu in Pb concentrate, 1.3% Zn in Pb concentrate, 26.1% Au in Pb concentrate, 48.7% Ag in Pb concentrate, 2.1% Cu in Zn concentrate, 4.5% Pb in Zn concentrate, 3.3% Au in Zn concentrate, 5.8% Ag in Zn concentrate. 5. Mineral Reserves are based on mining cost of $2.52/t incremented at $0.02/t/5m and $0.012/t/5m below and above 790 m elevation, respectively. 49 Table of Contents 6. Costs applied to processed material following: process operating cost of $18.31/t, G&A of $5.83/t, sustaining capital cost of $2.37/t, closure cost of $4.27/t, road toll cost of $8.04/t. 7. Strip ratio (waste:ore) is 7.3:1. 8. Selling terms following: payables of 96.5% of Cu, 95% of Pb and 85% of Zn, treatment costs of $80/t Cu concentrate, $160/t Pb concentrate and $215/t Zn concentrate; refining costs of $0.08/lb Cu in Cu concentrate, and$10/oz Au, $1.25/oz Ag in Pb concentrate; and transport cost $270.98/t concentrate. All selling terms are as of November 2022 and transport cost is as of July 2020. 9. Fixed royalty percentage of 1% NSR. The Arctic Mineral Reserves are subject to the types of risks common to open pit polymetallic mining operations that exist in Alaska and may be materially affected by the following risk factors include: ● Changes in the metal prices from what was assumed; ● Changes to the assumptions used to generate the cut-offs; ● Changes in local interpretations of mineralization geometry and continuity of mineralized zones; ● Changes to geological and mineralization shapes, and geological and grade continuity assumptions; ● Changes to density and domain assignments from what was assumed; ● Changes to geotechnical, hydrogeological design assumptions; ● Changes to mining and metallurgical recovery assumptions; ● Change to the input and design parameter assumptions that pertain to the open pit constraining the estimates; ● Assumptions as to concentrate marketability, payability and penalty terms; ● Assumptions as to the continued ability to access the site, retain mineral tenure and obtain surface rights titles, obtain environment and other regulatory permits, and maintain the social license to operate. More specifically the presence of certain talc layers in the rock have not been included in the current geological model and could affect the metallurgical recoveries and slope stability. Additionally, there is currently no developed surface access to the Arctic Project area and beyond. Access to the Arctic Project is proposed to be via AAP, a road approximately 340 km (211 miles) long, extending west from the Dalton Highway where it would connect with the proposed Arctic Project area. Construction costs of the road are not yet final. The working assumption is that AIDEA would arrange financing in the form of a public-private partnership to construct and arrange for the construction and maintenance of the access road. AIDEA would charge a toll to multiple mining and industrial users (including the Arctic Project) in order to pay back the costs of financing the AAP. The amount paid in tolls by any user would be affected by the cost of the road, its financing structure, and the number of mines and other users of the road which could also include commercial transportation of materials and consumer items that would use the AAP to ship concentrates to the Port of Anchorage in Alaska and possibly provide goods and commercial materials to villages in the region. The Mineral Reserve estimation assumes toll payments of $5.52/t processed, plus a road maintenance fee of $2.52/t milled processed, resulting in a total road toll and maintenance LOM unit cost of $8.04/t processed. There is a risk that a negotiated road toll agreement may result in higher costs than what has been assumed. Mining Operations The Arctic Project is designed as a conventional truck-shovel operation with 144 t trucks and 15 m 3 shovels. The pit design includes four nested phases to balance stripping requirements while satisfying the concentrator requirements. 50 Table of Contents The design parameters include a ramp width of 30 m, road grades of 10%, bench height of 5 m, targeted mining width between 70 m and 100 m, berm interval of 20 m, variable slope angles by sector and a minimum mining width of 30 m. The smoothed final pit design contains approximately 46.7 Mt of ore and 340.2 Mt of waste for a resulting stripping ratio of 7.3:1. Within the 46.7 Mt of ore, the average grades are forecasted to be 2.11% Cu, 2.90% Zn, 0.56% Pb, 0.42 g/t Au and 31.8 g/t Ag. The scheduling constraints set the maximum mining capacity at 35 Mt/a, and the maximum process capacity at 10 kt/d. The production schedule based on the Probable Mineral Reserves shows a total life-of-mine (LOM) of 15 years, including 2 years of pre-production and 13 years of production. Processing and Recovery Operations The 10,000 t/d process plant design is conventional for the industry and will operate two 12-hour shifts per day, 365 d/yr with an overall plant availability of 92%. The process plant will produce three concentrates: 1) copper concentrate, 2) zinc concentrate, and 3) lead concentrate. Gold and silver are expected to be payable at a smelter; both gold and silver is expected to be payable in the copper and lead concentrates. While there are several deleterious elements reporting to the concentrates at levels that could incur penalties, there are no special processing provisions required to make a readily saleable concentrate. The presence of naturally hydrophobic talc minerals was consistently observed in the various testwork programs. There is little reason to expect concentrates will be impaired by talc contamination as talc can be effectively removed from the flotation process prior to base metal flotation. Talc and fluorine levels will be managed by optimization of the talc pre-float circuit, effectively removing talc and fluorine to ensure the quality of the lead concentrate. The mill feed will be hauled from the open pit to a primary crushing facility where the material will be crushed by a jaw crusher to a particle size of 80% passing 80 mm. The crushed material will be ground by two stages of grinding, consisting of one SAG mill and one ball mill in closed circuit with hydrocyclones (SAB circuit). The hydrocyclone overflow with a grind size of approximately 80% passing 70 μm will first undergo talc pre-flotation, and then be processed by conventional bulk flotation (to recover copper, lead, and associated gold and silver), followed by zinc flotation. The bulk rougher concentrate will be cleaned and followed by copper and lead separation to produce a lead concentrate and a copper concentrate. The final tailings from the zinc flotation circuit will be pumped to a tailing management facility (“TMF”). Copper, lead, and zinc concentrates will be thickened and pressure-filtered before being transported by truck to a port and shipped to smelters. Based on the mine plan developed for the NI 43-101 Arctic Report and S-K 1300 Arctic Report and metallurgical testwork results, the LOM average metal recoveries and concentrate grades are presented in Table 10. Table 10 – LOM Average Recovery and Concentrate Grade Description Units Cu con Pb con Zn con LOM Production t/y 234,132 23,300 174,202 Grade % 30.3% Cu 53.9% Pb 53.7% Zn Recovery % 92.1% Cu 52.2% Au 32.5% Ag 61.3% Pb 21.6% Au 48.6% Ag 88.5% Zn ​ The recovery plan includes provision for reagents, and water and power requirements. 51 Table of Contents Infrastructure, Permitting and Compliance Activities Infrastructure The Arctic Project site is a remote, greenfield site that is remote from existing infrastructure. Infrastructure that will be required for the mining and processing operations will include: ● Open pit mine ● Stockpiles and Waste Rock Facility (“WRF”) ● Truck workshop, truck wash, mine offices, mine dry facility and warehouse ● Power house ● Administration building ● Mill dry facility ● Plant workshop and warehouse ● Primary crushing building ● Fine ore stockpile building ● Process plant and laboratory ● Concentrate loadout building ● Reagent storage and handling building ● Explosive storage silos and magazines ● Avalanche mitigation structures ● TMF ● Surface water diversion and collection channels, culverts, and containment structures ● Waste rock collection pond (“WRCP”) ● Process water pond ● Water treatment plant (“WTP”) ● Camp Access The Arctic Project site will be accessed through a combination of State of Alaska-owned highways (existing), an AIDEA-owned private road (proposed) and Ambler-owned access roads (proposed). The AAP road is proposed by AIDEA to connect the Ambler Mining District to the Dalton Highway. The AAP road expected to be permitted as a private road with restricted access for industrial use. To connect the Arctic Project site and the existing exploration camp to the proposed AAP road, an access road (the Arctic access road) will need to be built. 52 Table of Contents The State of Alaska-owned, public Dahl Creek airport will require upgrades to support the planned regular transportation of crews to and from Fairbanks. The cost of these upgrades has been included in the capital cost estimate. Power Power generation will be by five diesel generators, producing a supply voltage of 13.8 kV. The total connected load will be 25.9 MW with a normal running load of 21.0 MW. Diesel will be supplied via existing fuel supply networks in the region and shipped along the AAP road. Accommodation The Arctic Project will require three self-contained camps, in two different locations, equipped with their own power and heat generation capabilities, potable water treatment plant, sewage treatment plant, and garbage incinerator. The existing 90-person Bornite Camp currently used for exploration will be expanded and used to start the construction of the Arctic access road and the logistics yard and construction camp. This Bornite Camp will be expanded and available prior to surface access from the Dalton Highway via the AAP road. A 250-person construction camp (“CC”) will be constructed at a location near the intersection of the AAP road and Arctic Mine Access road, across the road from the Logistics Yard. CC will be constructed when limited access via the AAP is available for the transport of camp modules. A Permanent Accommodations Facility (“PAF”) will be constructed in the same location as CC. The PAF will be constructed when the AAP is available to transportation of the modules by truck and will be operating for about 2 years prior to the commissioning of the Arctic Mill and production of concentrates. During this period, it will be used to accommodate both construction personnel and the initial Ambler Metals Mine Operations and support personnel required for pre-production mining. Waste Rock Facility The WRF will be developed north of the Arctic pit in the upper part of the Subarctic Creek valley. The WRF is designed as part of the tailings dam structure to provide a buttress for tailings containment in the adjacent footprint. The total volume of waste rock is expected to be 162.6 Mm 3 (340 Mt); however, there is potential for expanded volume in the waste if placement density is <2.0 t/m 3 . The WRF will have a final height of 340 m to an elevation of 990 masl and is planned to be constructed in lifts of either 5, 10 or 20 m height with catch benches every 20 m to achieve an overall slope angle of 2.5H:1V. Most of the waste rock is anticipated to be potentially acid-generating and there will be no separation of waste based on acid generation potential. Rather, seepage from the WRF will be collected and treated. Overburden Stockpiles There will also be three small overburden stockpiles to store the stripped topsoil and overburden from the TMF and WRF footprint. The topsoil stockpile will be placed between the haul roads with capacity to store up to 325,000 m 3 while the overburden stockpile will be located south of the WRF to store up to 2,200,000 m 3 . Tailings Management Facility The TMF will be located at the headwaters of Subarctic Creek, in the upper-most portion of the creek valley. The 59 hectares footprint of the TMF will be fully lined with a geomembrane liner. Tailings containment will be provided by an engineered dam, buttressed by the WRF that will be constructed immediately downstream of the TMF and the natural topography on the valley sides. A starter dam will be constructed to elevation 830 m. Three subsequent raises will bring the final dam crest elevation to 892 m, which is 98 m lower than the final elevation of the WRF. The TMF is designed to store approximately 37.4Mm 3 (41.2 Mt) of tailings produced over the 13-year mine life, 3.3 Mm 3 of additional pond water, as well as 1.5 times the probable maximum flood, with 2.5 m of freeboard. Water Management 53 Table of Contents The proposed mine development is located in the valley of Subarctic Creek, a tributary to the Shungnak River. A surface water management system will be constructed to segregate contact and non-contact water. Non-contact water will be diverted around mine infrastructure to Subarctic Creek. A groundwater seepage monitoring and collection system will be located down gradient of the WRF and seepage collection pond. Contact water will be conveyed to treatment facilities prior to discharge to the receiving environment. A WRCP will be located directly below the toe of the WRF and will be used to collect seepage from the WRF, runoff from the WRF and haul road corridor area, and water pumped from the open pit. The Arctic Project water and load balance model was updated to include the current water management plan. The model indicates that during operations, excess water from the WRCP will need to be treated prior to discharge to the receiving environment. During closure, water from the dewatering of the TMF will also need to be treated prior to discharge to the receiving environment. Water Treatment Plant It was assumed the site will be assigned water quality-based effluent limits matching the state’s Water Quality Standards for the nearby Subarctic Creek. Therefore, the WTP is designed to treat all parameters in the predicted site wastewater to the WQS of Subarctic Creek. This will eliminate the need for a mixing zone and allow treated water to be discharged year-round if needed. A single WTP, built in stages, will be used. During Operations phase the WTP will treat effluent from the WRCP, and during Closure phase effluent from the pit. The WTP will initially consist of chemical/physical treatment with reverse osmosis (“RO”) filtration. During operations, the RO reject will be sent to the TMF, and only RO permeate will be discharged to Subarctic Creek. When the TMF is closed at the end of the operations, a biological/chemical/physical plant will be added to treat the RO reject. The biologic plant discharge will be mixed with the RO prior to discharge. Market Studies Metal pricing was guided by 3-year trailing average prices and long-term price forecasts from analysts as published by CIBC in 2022. The metal price assumptions used in the economic analysis: ● Copper: $3.65/lb ● Zinc: $1.15/lb ● Lead: $1.00/lb ● Gold: $1,650/oz ● Silver: $21.00/oz Smelter terms were prepared in January 2023 by StoneHouse Consulting Inc. Smelter terms were applied for the delivery of copper, zinc and lead concentrate. It was assumed that delivery of all concentrates would be to a smelter in the Asia Pacific region at currently available freight rates. Total transport costs for the concentrate are estimated at $324.37/dmt. Environmental, Permitting, Social and Closure Considerations Environmental Considerations The Arctic Project area includes the Ambler Lowlands and Subarctic Creek within the Shungnak River drainage. A significant amount of baseline environmental data collection has occurred in the area including surface and groundwater 54 Table of Contents quality sampling, surface hydrology monitoring, wetlands mapping, aquatic life surveys, avian and mammal habitat surveys, cultural resource surveys, hydrogeology studies, meteorological monitoring, and ML/ARD studies. Permitting Considerations Current mineral exploration activities are conducted at the Arctic deposit under State of Alaska and NWAB permits. The State of Alaska Miscellaneous Land Use Permit and the NWAB Permit both expired at the end of 2022 and will be renewed. Mine development permitting will be largely driven by the underlying land ownership with regulatory requirements varying depending on land ownership. The Arctic Project area includes patented mining claims (private land under separate ownership by Ambler Metals and NANA), State of Alaska land, and NANA land (private land) Because the infrastructure for the Arctic Project is situated to a large extent on State land, it will likely be necessary to obtain a Plan of Operation Approval (which includes the Reclamation Plan and Closure Cost Estimate) from the Alaska Department of Natural Resources (“ADNR”). The Arctic Project will also require certificates to construct and operate dams (tailings and water storage) from the ADNR (Dam Safety Unit) as well as water use and discharge authorizations, an upland mining lease and a mill site lease, as well as several minor permits including those that authorize access to construction material sites from ADNR. The Alaska Department of Environmental Conservation (“ADEC”) would authorize waste management under an Integrated Waste Management permit, air emissions during construction and operations under an air permit, and an Alaska Pollutant Discharge Elimination System permit for any wastewater discharges, and a Multi-Sector General Permit for stormwater discharges. The ADEC would also be required to review the US Army Corps of Engineers Section 404 permit to certify that it complies with Section 401 of the Clean Water Act (“CWA”). The Alaska Department of Fish and Game would have to authorize any culverts or bridges that are required to cross fish-bearing streams or other impacts to fish-bearing streams that result in the altering or affecting fish habitat. The U.S. Army Corps of Engineers (“USACE”) would require a CWA Section 404 permit for dredging and filling activities in Waters of the United States including jurisdictional wetlands. The USACE Section 404 permitting action would require the USACE to comply with the NEPA and, for a project of this magnitude, the development of an Environmental Impact Statement (“EIS”) is anticipated. The USACE would likely be the lead federal agency for the NEPA process. As part of the Section 404 permitting process, the Arctic Project will have to meet USACE wetlands guidelines to avoid, minimize and mitigate impacts to waters of the US including wetlands. The Arctic Project will also have to obtain approval for a Master Plan from the NWAB. In addition, actions will have to be taken to change the borough zoning for the Arctic Project area from Subsistence Conservation and General Conservation to Resource Development and Transportation. The overall timeline required for permitting would be largely driven by the time required for the NEPA process, which is triggered by the submission of the Section 404 permit application to the USACE. The timeline includes the development and publication of a draft and final EIS and ends with a Record of Decision and Section 404-permit issuance. In Alaska, the EIS and other State and Federal permitting processes are generally coordinated so that permitting and environmental review occurs in parallel. The NEPA process could require about three years to complete and could potentially take longer. Social and Community The Arctic Project is located approximately 40 km northeast of the villages of Shungnak and Kobuk, and 65 km east-northeast of the community of Ambler. The population in these villages are 151 in Kobuk (2020 Census), 210 in Shungnak (2020 Census), and 275 in Ambler (2020 Census). Residents largely live a subsistence lifestyle with incomes supplemented 55 Table of Contents by guiding, local development projects, employment through tribal and city councils, government aid, and employment both in and outside of their home villages. The Arctic Project has the potential to significantly improve work opportunities for residents during the exploration phase, construction, and during full operation. Trilogy’s joint venture, Ambler Metals works directly with the Upper Kobuk villages and communities throughout the region to employ residents as mechanics, geotechnicians, core cutters, administrative staff, camp services, heavy equipment operators, drill helpers, and environmental technicians. Stakeholder outreach and community meetings in the region by the Arctic Project’s owners over many years have provided the opportunity to engage with residents, provide updated information on the project and future plans for the Upper Kobuk Mineral Project, hear concerns, answer questions, and build relationships. This engagement has also identified various hurdles residents have faced when applying for employment. Opportunities have been created for NANA shareholders to apply and receive educational scholarships, participate in job shadowing at Bornite, driver’s license courses, and heavy equipment operator training sponsored by the Arctic Project’s owners. It is the company’s goal to continue and grow these efforts throughout the permitting process and the life of the project – encouraging and supporting education, job training, employment, and economic growth. Closure Planning Mine reclamation and closure are largely driven by State of Alaska regulations that specify that a mine must be reclaimed concurrent with mining operations to the greatest extent possible and then closed in a way that leaves the site stable in terms of erosion and manages degradation of water quality from acid rock drainage or metal leaching on the site. A detailed Reclamation Plan and Closure Cost Estimate will be submitted to the State of Alaska agencies for review and approval in the future, during the formal mine permitting process. Owing to the fact that the Arctic Project is likely to have facilities on a combination of private (patented mining claims and native land) and State land, the Reclamation Plan will be submitted and approved as part of the Plan of Operations, which is approved by the ADNR. However, since the Reclamation and Closure plan must meet regulations of both ADNR and the ADEC, both agencies will review and approve the Reclamation Plan and Closure Cost Estimate. In addition, private landowners must formally concur with the portion of the Reclamation Plan for their lands so that it is compatible with their intended post-mining land use. The estimated closure costs are determined from unit rates based on projects located in Alaska. The indirect costs were included as percentages of the estimated direct costs. Long-term water treatment and maintenance of certain water management facilities were calculated separately, and a net present value (“NPV”)value is provided for the first 100 years, at a discount rate of 4.3%. Annual undiscounted costs associated with long-term operations of the WTP are estimated to be $11.7 million in Phase 1 closure (15-years post-closure) and $10.8 million in Phase 2 closure (85 years thereafter), amounting to $1,095 million over the 100-year closure period. These costs equate to $258 million when discounted at 4.3% p.a. to the first year of post-production. Capital and Operating Costs Capital Costs The capital cost estimate has an estimated accuracy of ±15% and uses Q3/Q4-2022 US dollars as the base currency within an estimated contingency of ±15%. The total estimated initial capital cost for the design, construction, installation, and commissioning of the Arctic Project is estimated to be $1,177 million. A summary of the estimated initial capital cost, sustaining capital cost and closure costs is shown in Table 11. 56 Table of Contents Table 11 – Capital Cost Summary WBS Level 1 WBS Level 1 Description Initial Capex ($ M) Sustaining Capex ($ M) Total Capex ($ M) 1000 Mining 277.4 17.5 294.9 2000 Crushing 42.5 0 42.5 3000 Process Plant 158.0 1.3 159.3 4000 Tailings 88.3 32.4 120.7 5000 On-site Infrastructure 172.8 35.1 207.9 6000 Off-site Infrastructure 75.8 0 75.8 Sub-total Direct Costs 834.1 86.3 920.4 7000 Indirects 177.4 15.1 192.5 8000 Provisions (Contingency) 138.5 13.0 151.5 9000 Owner Costs 26.8 0 26.8 Sub-total Indirect Costs 342.7 28.1 370.8 Project Total 1,176.8 114.4 1,291.2 Project Total – Closure Costs 170.8 ​ Operating Costs An average operating cost was estimated for the Arctic Project based on the proposed mining schedule. These costs included, mining, processing, G&A, surface services, and road toll costs. The average LOM operating cost for the Arctic Project is estimated to be $59.83/t milled. The breakdown of costs in Table 12 is estimated based on the LOM average mill feed rate of 3,650,000 t/y. All pre-production costs have been included in the capital cost estimate in “Properties – Arctic Project—Capital and Operating Costs – Capital Costs” above. 57 Table of Contents Table 12 – Overall Operating Cost Estimate Description LOM Average Unit Operating Cost ($/ t milled) Percentage of Total Annual Operating Costs Mining* 22.49 37.6% Processing 22.60 37.8% G&A 5.85 9.8% Road Toll and Maintenance 7.72 12.9% Water Treatment 1.17 2.0% Total Operating Cost 59.83 100% * Excludes pre-production costs Economic Analysis The results of the economic analyses discussed in this section represent forward-looking information as defined under U.S. and Canadian securities law. The results depend on inputs that are subject to several known and unknown risks, uncertainties, and other factors that may cause actual results to differ materially from those presented herein. Information that is forward-looking includes the following: Probable Mineral Reserves that have been modified from Indicated Mineral Resource estimates; assumed commodity prices and exchange rates; proposed mine and process production plan; projected mining and process recovery rates; ability to market the three types of concentrate on favourable terms; ability to control the levels of deleterious elements in some of the concentrate batches; sustaining costs and proposed operating costs; assumptions as to closure costs and closure requirements, including WTP requirements; assumptions as to development of the Ambler Access Project, timeframe of such development and assumed toll charges; assumptions as to ability to permit the project; assumptions about environmental, permitting and social risks. An economic analysis was undertaken on a 100% project ownership basis to determine the internal rate of return (“IRR”), NPV and payback on initial investment of the Arctic Project. Trilogy holds a 50% interest in the Arctic Project though its ownership in Ambler Metals. The Arctic Project consists of a three-year construction period, followed by 13 years of production. The pre-tax financial model incorporated the production schedule and smelter term assumptions to produce annual recovered payable metal, or gross revenue, in each concentrate stream by year. Off-site costs, including the applicable refining and treatment costs, penalties, concentrate transportation charges, marketing and representation fees, and royalties were then deducted from gross revenue to determine the NSR. The operating cash flow was then produced by deducting annual mining, processing, G&A, surface services, and road toll & maintenance charges from the NSR. Initial and sustaining capital was deducted from the operating cash flow in the years they occur, to determine the net cash flow before taxes. Initial capital cost includes all estimated expenditures in the construction period, from Year -3 to Year -1 inclusive. First production occurs at the beginning of Year 1. Sustaining capital expenditure includes all capital expenditures purchased after first production, including mine closure and rehabilitation. The model includes an allocation of a 1% NSR attributable to NANA. With total capital costs of $1,719 million over LOM ($1,177 million initial capital cost, $114 million sustaining capital cost and $428 million closure costs), the project demonstrates a pre-tax NPV of $1,500 million at an 8% discount rate, IRR of 25.8% and payback period of 2.9 years. Post-tax financials have an NPV of $1,108 million at an 8% discount rate, IRR of 22.8% and payback period of 3.1 years. The estimated cash flow forecast over LOM is $3,942.6 million undiscounted pre-tax cash flow, $1,500.3 million discounted pre-tax cash flow at an 8% discount rate, $3,019.9 million undiscounted post-tax cash flow and $1,108.1 discounted post-tax cash flow at an 8% discount rate. 58 Table of Contents Sensitivity Analysis Ausenco investigated the sensitivity of the Arctic Project’s pre-tax NPV, and IRR to several project variables. The following variables were elected for this analysis: ● Copper price ● Zinc price ● Lead price ● Gold price ● Silver price ● Capital costs ● On-site operating costs ● Off-site operating costs (royalties, refining and treatment charges, penalties, insurance, marketing, and representation fees, and concentrate transportation) Each variable was changed in increments of 10% between -20% to +20% while holding all other variables constant. The project NPV at an 8% discount rate is most sensitive to changes in copper price, followed by off-site operating costs, on-site operating costs, zinc price, capital costs, silver price, gold price and lead price. Exploration, Development, and Production Constraints and Interfaces The Arctic Project will be an integrated development with several consultants contributing to the overall design process. Specialist contractors will most likely be engaged for specific packages, such as the Arctic access road, and the construction camps, generally on a “design and construct” basis. It is essential that these parties work together to ensure data being used is both current and meaningful. Data transfer between parties shall be strictly controlled and in accordance with Document Control protocols. The early design interfaces for the Arctic Project will include at least: ● Mine development ● Waste Rock placement and Tailings Dam ● Arctic Project water management and treatment ● Arctic Access Road design and construction, in particular the pioneer road necessary to allow earliest possible access to the Mine pre-assembly construction site ● Bornite, Construction and Permanent Camps The Interface Management procedures will be developed to ensure services at the battery limits are clearly defined and understood by all parties affected. Key Project Milestones 59 Table of Contents Key project milestones will be developed once the project is committed to construction and the required permits are in hand. The Mine requires nominally two years of pre-strip operations, tailings pond starter dam development and water accumulation before actual production mining operations can commence. For that pre-strip work to start, the Arctic access road from the AAP intersection to the mine site will have to be constructed to at least a pioneer road condition that will allow the mine fleet and the support facilities to be delivered, built and made operational. Tailings pond construction must be to a height to allow natural collection of water in quantities that will allow plant operations to commence. Proven Technology The Arctic Project will utilize proven technology and equipment that can be built, operated and maintained under adverse weather conditions. The Design Criteria, Technical Specifications and Data sheets shall reflect the location, the environmental and initial logistics constraints that may affect the procurement and construction effort. Engineering, Procurement and Construction Management Approach Two engineering, procurement and construction management (“EPCM”) strategies have been identified that are structured to account for the abnormally long pre-strip mining operation. The first option is the basis for the capital and operating cost estimate. Early Engineering Only with 2-Stage Procurement There is a need to establish the mine facilities and assemble the Mine Fleet in time to allow the pre-strip operation to start some two years before the Process Plant receives its first ore. This means that there will be a significant amount of detailed engineering requiring completion well in advance of the time required for conventional engineering, procurement and construction of just the process plant and supporting infrastructure. This has been assessed as requiring detailed engineering to start some four years before the process plant starts production. In particular, the pioneer access road design and contracts and civil design for the Mine Support facilities will be required early in the schedule. By default, the rest of the civil design would need to attach to that early works for simple plant layout and construction coordination purposes. For that to occur the plant layout will be required to be established at an early stage. That in turn is dependent on sizing and selection of the major process equipment items and the receipt of vendor data to complete the plant layout. Effectively, the detailed design phase will need to follow the conventional approach and run its course but started at a time that meets the early works schedule requirements. Everything other than the mine support facilities will be designed some two years in advance of when it is needed. With the early equipment order placement, the supply phase could become inordinately long, extending over three years in most cases, when in fact the equipment is not likely to be needed until the last eighteen months prior to plant start¬up. An unorthodox but proven option to this extended design, supply and construction schedule is to have the EPCM Contractor procure the major equipment in two steps: ● Step 1: Procure only the vendor certified engineering data to allow detailed engineering to continue to completion but hold the manufacturing functions until later in the overall schedule, effectively a delay of around twelve to fifteen months. 60 Table of Contents ● Step 2: Based on agreed vendor manufacturing durations, apply a “late” release of the equipment for manufacture with deliveries effectively becoming a “Just-in Time” logistics operation. This strategy provides the following advantages: ● Engineering can start and continue to completion using critical certified vendor data without the need for an extended “standby” involvement. ● Procurement functions can work in parallel with the engineering group with no disconnect between the two disciplines. ● The procurement team can generally disband early in the schedule with just key personnel retained to provide continuity of support. ● The expediting team can mobilize later in the schedule to drive manufacture and delivery in a concerted campaign. ● Equipment deliveries can be orchestrated to suit the conditions at the time with everything consolidated into a transit compound for coordinated shipping to site. ● Reduced cashflow demands. Potential issues to be mitigated with this approach are: ● The vendors need to be clearly briefed as to what the system means to their manufacturing schedule. ● A payments formula needs to be in place to account for a delayed delivery strategy. ● Some vendors have difficulty in determining just what their actual engineering costs are. Early EPCM Leading to Plant Care and Maintenance Under this approach, the EPCM would work to conventional design and construction schedule, starting to suit the mine access requirements but following on to completion without interruption. That would bring the total process plant and supporting infrastructure to a mechanical completion condition nominally twelve to fifteen months before it is able to start work. The plant could not be commissioned through lack of ore and would have to be placed into care and maintenance mode until ore became available. This has an inherent advantage in that if the pre-strip operation was completed earlier than scheduled, and sufficient water is accumulated, the plant operations would be able to take advantage of the fact the plant was already mechanically complete. The care and maintenance requirements in that environment for that duration will require close assessment. Interpretations and Conclusions The Arctic deposit will be mined at an maximum annual rate of 35 Mt of ore per year with an overall stripping ratio of 7.3. Ore will be processed by conventional methods to annually produce 234 kt of copper, 23 kt of lead, and 174 kt of zinc, all in concentrates for provision to third party refiners. Waste and tailings materials will be stored in surface facilities, which will be closed and reclaimed at the end of the mine; contact water will be treated and discharged to the environment throughout the life of mine. Precious metals attendant with the concentrates will be largely payable. While 61 Table of Contents there are deleterious elements reporting to the concentrates at levels that could incur penalties, special processing provisions have been included in the flowsheet to make a readily saleable concentrate. In terms of project execution, the mine requires nominally two years of pre-strip operations, tailings pond starter dam development and water accumulation before actual production mining operations can commence. For that pre-strip work to start, the Arctic access road from the Ambler Access Project intersection to the mine site will have to be constructed to at least a pioneer road condition that will allow the mine fleet and the support facilities to be delivered, built, and made operational. Based on $1,177 million of initial capital costs, sustaining capital costs of $114 million, closure costs of $428 million, $2,969 million in LOM off-site operating costs and $2,794 million in LOM on-site operating costs, pre-tax financial results show a project IRR of 25.8% and an NPV of $1,500 million at an 8% discount rate and a 2.9-year payback period. Post-tax results show a project IRR of 22.8% and NPV of $1,108 million at an 8% discount rate and a 3.1-year payback period. Mineral Reserve and Resource Estimate Comparison Between November 30, 2024 and 2023 Mineral Reserves Comparison for Arctic There were no changes to the mineral reserve estimates for the Arctic project from November 30, 2023 to November 30, 2024. Mineral Resources Comparison for Arctic There were no changes to the mineral resource estimates for the Arctic project from November 30, 2023 to November 30, 2024. Bornite Project The Company is subject to and required to disclose mineral resources and mineral reserves in accordance with S-K 1300. While the S-K 1300 rules are similar to NI 43-101 rules in Canada, they are not identical and therefore two reports have been produced for the Bornite Project. The information in Item 2, Properties, contains pertinent information required under both NI 43-101 and S-K 1300. Except as otherwise stated, the scientific and technical information relating to the Bornite Project contained in this Form 10-K is derived from the (i) 2025 S-K 1300 report for Bornite titled “S-K 1300 Technical Report Summary on the Initial Assessment of the Bornite Project, Northwest Alaska, USA” dated November 30, 2024 prepared by Wood Canada Limited, SRK Consulting (Canada) Inc., Ausenco Engineering Canada ULC. and International Metallurgical & Environmental and Core Geoscience LLC, which are each unaffiliated with Trilogy (“S-K 1300 Bornite Report” or the “Bornite Study”) and the (ii) technical report titled “NI 43-101 Technical Report on the Preliminary Economic Assessment of the Bornite Project, Northwest Alaska, USA”with an effective date of January 15, 2025, prepared by Wood Canada Limited, SRK Consulting (Canada) Inc., Ausenco Engineering Canada ULC. and International Metallurgical & Environmental and Core Geoscience LLC, which are each unaffiliated with Trilogy (the “NI 43-101 Bornite Report”). The information regarding the Bornite Project is based on assumptions, qualifications and procedures which are not fully described herein. Reference should be made to the full text of the S-K 1300 Bornite Report and the NI 43-101 Bornite Report which has been filed, as applicable, with certain Canadian securities regulatory authorities pursuant to NI 43-101. The NI 43-101 Bornite Report is available for review on SEDAR+ at www.sedarplus.ca and the S-K 1300 Bornite Report is available for review on EDGAR at www.sec.gov. ​ Property Description, Location, and Access 62 Table of Contents The Bornite property is located in the Ambler Mining District of the southern Brooks Range in the NWAB of Alaska. The property is located in Ambler River A-2 quadrangle, Kateel River Meridian T 19N, R 9E, sections 4, 5, 8 and 9. The Bornite Project is located 248 km east of the town of Kotzebue, 19 km north of the village of Kobuk, 275 km west of the Dalton Highway (an all-weather state maintained public road) at geographic coordinates N67.07° latitude and W156.94° longitude (Universal Transverse Mercator North American Datum 83, Zone 4W coordinates 7440449N, 589811E). Primary access to the Bornite Project is by air, using both fixed wing aircraft and helicopters. There are four well maintained, approximately 1,500 m-long gravel airstrips located near the property, capable of accommodating charter fixed wing aircraft. These airstrips are located 40 km west at Ambler, 23 km southwest at Shungnak, 19 km south at Kobuk, and 15 km south at Dahl Creek. There is daily commercial air service from Kotzebue to the village of Kobuk, the closest community to the property. There are also flights between Fairbanks and some of the local villages. During the summer months, the Dahl Creek airstrip is suitable for larger aircraft, such as C-130 and DC-6. There is also a 700 m airstrip located at the Bornite camp. The airstrip at Bornite is suited to smaller aircraft, which support the Bornite camp with personnel and supplies. A two-lane, two-wheel drive gravel road links the Bornite camp to the 1,525 m Dahl Creek airstrip and village of Kobuk. On February 11, 2020, Trilogy Metals transferred the UKMP, including the Bornite property, to a 50/50 joint venture named Ambler Metals. With NANA’s approval, Trilogy Metals also contributed, along with the UKMP, its rights under the NANA Agreement to Ambler Metals while its joint venture partner, South32, contributed $145 million. The NANA Agreement provides that NANA will grant Trilogy Metals the nonexclusive right to enter onto, and the exclusive right to explore, the Bornite Lands and the ANCSA Lands (each as defined in the NANA Agreement) and in connection therewith, to construct and utilize temporary access roads, camps, airstrips, and other incidental works. The NANA Agreement has a term of 20 years, with an option in favour of Trilogy Metals to extend the term for an additional 10 years. The NANA Agreement may be terminated by mutual agreement of the parties or by NANA if Trilogy Metals does not meet requirements of aggregate expenditures over two consecutive calendar years are not at least $600,000 on NANA’s lands. Trilogy Metals has confirmed they met this expenditure requirement to date. The NANA Agreement outlines a partnership agreement for the development of the UKMP. If, following receipt of a feasibility study and the release for public comment of a related draft environmental impact statement, Ambler Metals decides to proceed with construction of a mine on the lands subject to the NANA Agreement, Ambler Metals will notify NANA in writing and NANA will have 120 days to elect to either (a) exercise a non-transferrable back-in-right to acquire between 16% and 25% (as specified by NANA) of that specific project; or (b) not exercise its back-in-right, and instead receive a net proceeds royalty equal to 15% of the net proceeds realized by Ambler Metals from such project. The cost 63 Table of Contents to exercise such back-in-right is equal to the percentage interest in the property multiplied by the difference between (i) all costs incurred by Ambler Metals or its affiliates on the property, including historical costs incurred prior to the date of the NANA Agreement together with interest on the historical costs; and (ii) $40 million (subject to exceptions). This amount will be payable by NANA to Ambler Metals in cash at the time the parties enter into a joint venture agreement and in no event will the amount be less than zero. In the event that NANA elects to exercise its back-in-right, the parties will, as soon as reasonably practicable, form a joint venture with NANA electing to participate between 16% to 25%, and Ambler Metals will own the balance of interest in the joint venture. Upon formation of the joint venture, the joint venture will assume all obligations of Ambler Metals and be entitled to all the benefits of Ambler Metals under the NANA Agreement in connection with the mine to be developed and the related lands. A party’s failure to pay its proportionate share of costs in connection with the joint venture will result in dilution of its interest. Each party will have a right of first refusal over any proposed transfer of the other party’s interest in the joint venture other than to an affiliate or for the purposes of granting security. A transfer by either party of a NSR royalty on the property or any net proceeds royalty interest in the property other than for financing purposes will also be subject to a first right of refusal. In connection with possible development on the Bornite Lands, Ambler Metals and NANA will execute a mining lease to allow Ambler Metals or the joint venture to construct and operate a mine on the Bornite Lands. These leases will provide NANA a 2% NSR royalty as to production from the Bornite Lands. If Ambler Metals decides to proceed with construction of a mine on its own lands subject to the NANA Agreement, NANA will enter into a surface-use agreement with Ambler Metals which will afford Ambler Metals access to the project along routes approved by NANA. In consideration for the grant of such surface use rights, Ambler Metals will grant NANA a 1% NSR royalty on production and an annual payment of $755 per acre (as adjusted for inflation each year beginning with the second anniversary of the effective date of the NANA Agreement and for each of the first 400 acres (and $100 for each additional acre) of the lands owned by NANA and used for access which are disturbed and not reclaimed. Environmental Liabilities Under the NANA Agreement, NANA is required to complete a baseline environmental report following the cleanup of the former mining camp on the Bornite Lands; this work must be completed to Alaska Department of Environmental Conservation standards. Cleanup includes the removal and disposal, as required by law, of all hazardous substances present on the Bornite Lands. NANA has indemnified and will hold Trilogy Metals harmless for any loss, cost, expense, or damage suffered or incurred attributable to the environmental condition of the Bornite Lands at the date of the baseline report which relate to any activities prior to the date of the agreement. Reclamation of mineral exploration activities at the Bornite property is completed under the guidelines presented by the State of Alaska in the Multi-Year Hardrock Exploration Permit #2183 issued by the Department of Natural Resources Division of Mining, Land, and Water. Permits Multiple permits are required during the exploration phase of the Bornite property. Permits are issued from Federal, State, and Regional agencies, including: the Environmental Protection Agency, US Army Corps of Engineers, ADEC, Alaska Department of Fish and Game, ADNR, and NWAB. The State of Alaska permit for exploration on the Bornite property, known as the Annual Hardrock Exploration Activity (“AHEA”) Permit, is obtained and renewed every five years through the ADNR – Division of Mining, Land and Water. Trilogy Metals held an AHEA exploration permit in good standing with the ADNR and has done so each year since 2004 under Alaska Gold. The Bornite property is within the NWAB therefore requiring a Title 9 Miscellaneous Land Use permit for mineral exploration, fuel storage, gravel extraction, and the operation of a landfill. The Bornite camp, Bornite landfill, and Dahl Creek camp are permitted by the ADEC. After the formation of the joint venture, Ambler Metals has renewed the necessary permits for exploration and related camp operations. 64 Table of Contents As the Bornite Project progresses, additional permits for environmental baseline and engineering studies will be necessary at Federal, State, and Regional levels. The NANA Agreement made in October 2011 includes the promotion of education opportunities for shareholders in the region. Ambler Metals have been periodically meeting with neighbouring communities providing updates on project plans and participate in a subsistence advisory committee with representatives from NANA Region villages and NANA. The QP is not aware of any significant factors and risks that may affect access, title, or the right or ability to perform work on the Bornite property other than what is described in the NI 43-101 Bornite Report and the S-K 1300 Bornite Report. The mineral resource estimates with respect to the Bornite Project are reported on a 100% basis, of which Trilogy’s share is 50%. History Kennecott and Bear Creek Mining Tenure Prospectors in search of gold, travelling up the Kobuk River in 1898 to 1899 found several small gold placer deposits in the southern Cosmos Hills that were worked intermittently over the ensuing decades. Around this time, copper mineralization at Ruby Creek and Pardner Hill was explored using small shafts and adits. At Ruby Creek, Smith describes bornite and chalcopyrite and lesser amounts of galena and pyrite filling open spaces in brecciated zones in limestone and in places replacing dolomite breccia. In 1947, Rhinehart “Rhiny” Berg staked claims over the Ruby Creek prospects, carried out extensive trenching and the first diamond drilling, and constructed an airstrip for access. In 1957, BCMC, Kennecott’s exploration subsidiary, optioned the property from Berg. Exploration drilling in 1961 and 1962 culminated in the discovery of the “No.1 Ore Body” where drill hole RC-34 cut 20 m of 24% Cu (the “No. 1 Ore Body” is a historical term used by BCMC that does not connote economic viability in the present context; it is convenient to continue to use the term to describe exploration work in a specific area that was previously referred to as the Ruby Creek Zone and is now referred to as simply the Ruby Zone). The discovery of the “No. 1 Ore Body” led to the development of an exploration shaft in 1965 through 1966, the development of an exploration drift and the completion of underground drilling in 1967. The discovery of the Arctic project in 1965 prompted a hiatus in exploration at Bornite, and only limited drilling occurred up until 1997. In the late 1990s, Kennecott resumed its evaluation of the Bornite deposit and the mineralization in the Cosmos Hills with an intensive soil, stream, and rock chip geochemical sampling program using a 32-element inductively couple plasma (“ICP”) analyses. Grid soil sampling yielded 765 samples. Ridge and spur sampling resulted in an additional 850 soil samples in the following year. Skeletonized core samples (85 samples) from key historical drill holes were also analyzed using 32 element ICP analytical methods. Geochemical sampling identified multiple areas of elevated copper and zinc in the Bornite region. Kennecott completed numerous geophysical surveys as an integral part of exploration throughout its tenure on the Bornite property. Various reports, notes, figures, and data files stored in Kennecott’s Salt Lake City exploration office indicated that geophysical work included, but was not limited to, the following: ● Airborne magnetic and EM surveys (fixed-wing INPUT) (1950s) ● Gravity, single point, audio-frequency magnetotelluric, EM, borehole and surface induced polarization (“IP”)/resistivity surveys (1960s) ● Gravity, airborne magnetic, and controlled-source audio-frequency surveys (1990s). We have minimal information or documentation associated with these geophysical surveys conducted prior to the 1990s. Where data are available in these earlier surveys, the lack of details in data acquisition, coordinate systems, and data 65 Table of Contents reduction procedures limit their usefulness. The only complete geophysical report that is available concerns down-hole IP/resistivity results. Most notable is the 1996 Bouguer gravity survey from the Bornite deposit into the Ambler Lowlands. The Bornite deposit itself is seen as a significant 3 milligal anomaly. Numerous 2 milligal to > 6 milligal anomalies occur under cover in the Ambler Lowlands and near the Aurora Mountain and Pardner Hill occurrences. In addition to the geophysical surveys conducted by Kennecott, the ADNR completed an aeromagnetic survey of portions of the Ambler Mining District in 1974-1975. Several studies have been undertaken reviewing the geology and geochemistry of the Bornite deposit. Most notable is Murray Hitzman’s PhD dissertation at Stanford University and Don Runnel’s PhD dissertation at Harvard University. Bernstein and Cox reported on mineralization of the “No. 1 Ore Body” in a 1986 paper in Economic Geology. Kennecott conducted two technical reviews of the groundwater conditions and a summary of the findings related to the flooding of the exploration shaft. In 1961, Kennecott collected 32 coarse reject samples from five drill holes to support preliminary metallurgical test work at Bornite. Samples targeted high-grade (> 10%) copper mineralization from the Upper Reef at the Ruby Zone. Geological Setting, Mineralization and Deposit Types Geology The Bornite Project is located within the Arctic Alaska Terrane, a sequence of mostly Paleozoic continental margin rocks that make up the Brooks Range and North Slope of Alaska. It is within the Phyllite Belt geologic subdivision, which together with the higher-metamorphic grade Schist Belt, stretches almost the entire length of the southern Brooks Range and is considered to represent the hinterland of the Jura-Cretaceous Brookian orogeny. The southern margin of the Phyllite Belt is marked by mélange and low-angle faults associated with the Kobuk River fault zone, while the northern boundary is thought to be gradational with the higher-grade metamorphic rocks of the Schist Belt. The geology of the Bornite resource area is composed of alternating intervals of carbonate rocks (limestone and dolostone) and calcareous phyllite. Limestone transitions laterally into dolostone near zones of mineralization and is considered hydrothermally altered. Spatial relationships and petrographic work suggest that dolomitization is genetically related to early stages of the copper mineralizing system; however, recent re-logging has questioned this view. In 2015, Trilogy tried to improve the understanding of the distribution and nature of the various lithologic units and their context within a sedimentary depositional model. A new interpretation, based on lithogeochemical signatures of the various units along with their historical visual logging, concluded that stacked debris flows composed of basal non-argillaceous channelized breccias were overlain by upward fining upward sequence of increasingly argillaceous breccias capped by high calcium (Ca) phyllites, confined laterally in channels between either massive or thin-bedded platform carbonates. Two mineralized stacked debrite successions were named the Lower and Upper Reefs. The Upper Reef grades upward into argillaceous limestones instead of discrete high Ca phyllites indicating a waning of debris supply. Based on this interpretation, a series of individual debrites were identified and modeled. In contrast to the locally derived high-Ca phyllites of the debrite-dominated Bornite carbonate sequence, low calcium (Ca) phyllites are abundant in the allochthonous Anirak schist (quartz phyllite) and the Beaver Creek phyllite that underlie and overlie the Bornite carbonate sequence, respectively. In addition to depositional lithostratigraphy, a cross-cutting mineralized breccia called the P-Breccia has been identified in and around the South Reef deposit. Though poorly defined due to lack of drilling in the area, the P-Breccia zone—which contains excellent copper grade—lies at the apex of the Iron Mountain discontinuity. Although clearly post-deformational, it remains unclear whether the P-Breccia is a post-depositional structural, hydrothermal or solution-collapse breccia. A short lithostratigraphic project carried out during the 2021 field season updated the interpretation of the depositional environment of the Bornite succession; this resulted in significant differences when compared to the previously summarized interpretations. The Bornite succession is now understood to be a carbonate slope deposit characterized by 66 Table of Contents (a) lime mudstone, exported to the slope from a contemporaneous shallow-marine carbonate factory, variably mixed with and interlayered with (b) background argillaceous sediment that is locally carbonaceous. Superimposed on these calcite-dominated normal slope strata are locally impressive thicknesses of dolomudstone-clast conglomerate (formerly breccia). Slope limestone and siltstone-mudstone were originally centimetrically to decimetrically bedded, but are commonly ductilely deformed, producing the variably limey phyllites that exhibit sub-mm scale foliation. In contrast, the dolostone-clast conglomerates and individual dolomudstone clasts responded brittlely to Brookian stress and show no significant shearing or plastic deformation. Instead, plastic deformation is largely restricted to the various phyllitic layers around the peripheries of the dolostone bodies. Structural fabrics observed on the Bornite property include rare bedding and two distinct metamorphic foliations. Bedding (S0) can be measured only rarely where phyllite and carbonate are interbedded and it is unclear to what extent it is transposed. The pervasive foliation (S1) is often mylonitic and exhibits both an imprinted stretching lineation and preferred top direction. It is easily measured in phyllites and is commonly reflected by colour banding and/or stylolamination (flaggy habit in outcrop) of the carbonates. Some limestone outcrops, in particular the thin bedded limestone on Aurora Mountain and the marbles at the base of Coral Hill, also exhibit a stretching lineation. Core-logging shows that S1 is folded gently on a 10 m scale and locally tightly folded at the decimetre scale forming a common S2 axial planar cleavage. S2 is folded gently on a 10 m scale forming an upright mesoscale S3 foliation. S1 and S3 foliations are thought to be Jura-Cretaceous in age. Structural mapping in 2021 recognized a well-developed stretching lineation (i.e., L-tectonite) in the carbonate-phyllite rocks, typically oriented shallowly towards the north-northeast or south-southwest. Top directions indicate movement to the south or south-southwest along the vector of the stretching lineation. Moreover, new mapping indicates that stiff Bornite rocks, in particular metric to hectametric dolostone bodies, have been boudinaged into 3D ellipsoids. Slip is accommodated by phyllites. Interpretation of this mapping should be performed to determine whether such a tectonic style plays a role in the distribution of copper mineralization. Owing to their greater rigidity, dolostone bodies of secondary dolostone manifest strain differently: tan hydrothermal dolostone tends to be broken into centimetre- to decimetre-scale blocks, whereas grey (diagenetic?) dolostone may exhibit unusual, contorted forms, some resembling human fingers or swan necks, as evident in outcrop. Dolostone is rarely cut by plastically deformed zones and instead forms metric to hectametric lenses (augens) encased in plastically deformed calc-mylonite and calc-phyllite. This deformation, presumably a product of the Jura-Cretaceous Brookian orogeny, complicates sedimentological interpretations. Mineralization at Bornite forms tabular mineralized zones that coalesce into crudely stratabound bodies hosted in dolostone conglomerate/breccia. Two significant dolomitic horizons that host mineralization have been identified by drilling and include: 1) the Lower Reef, a substantial 100 m to 300 m thick dolomitized zone lying immediately above the basal quartz phyllite unit of the Anirak schist and 2) the Upper Reef, a 100 m to 150 m thick dolomite horizon that sits roughly 300 m higher in the section. The Lower Reef is separated from the Upper Reef by a zone of ductilely sheared phyllites up to 60 m thick. The Lower Reef dolostone outcrops along the southern margin of the Ruby Zone and is spatially extensive throughout the deposit area. It hosts a significant portion of the shallow mineral resources in the Ruby Zone as well as higher grade mineral resources down-dip and to the northeast in the South Reef area. The Upper Reef hosts relatively high-grade mineral resources to the north in the Ruby Zone. The Upper Reef appears to lie at an important northeast-trending facies transition to the northwest of the main drilled area and appears to be at least partially thrust over the Lower Reef stratigraphy to the southeast. Drill results from 2013 show dolomitization and copper mineralization in the Upper and Lower Reefs coalescing into a single unit along the northern limits of current exploration. The northeast- trending Ruby Zone and South Reef areas also coalesce into a roughly 1,000 m wide zone of >200 m thick dolomite containing significant copper mineralization dipping north at roughly 5 to 10°. The 2017 drill results show that the mineralized dolomite interval continues for at least another 700m down-dip to the northeast from mineralization in the Upper and Lower Reefs. 67 Table of Contents Mineralization Copper mineralization at Bornite comprises chalcopyrite, bornite, and chalcocite distributed in stacked, stratabound zones exploiting favourable lithologies (conglomerate/berccia) within the Bornite sequence. Mineralization occurs, in order of increasing grade, as disseminations, irregular and discontinuous stringer-style veining, breccia matrix replacement, and stratabound massive sulphides. The distribution of copper minerals is zoned around the bottom-centre of each zone of mineralization, with bornite-chalcocite-chalcopyrite at the core progressing outward to a fringe of chalcopyrite-pyrite. Additional volumetrically minor copper minerals include carrollite, digenite, tennantite-tetrahedrite, and covellite. Stringer pyrite and locally significant sphalerite occur above and around the copper zones and locally massive pyrite and sparse pyrrhotite are associated with siderite alteration below copper mineralization in the Lower Reef. Significant cobalt mineralization is found accompanying bornite-chalcocite mineralization. Cobalt often occurs with high-grade copper as carrollite (Co2CuS4) and as cobaltiferous rims on recrystallized pyrite grains. Preliminary geometallurgical work by Trilogy showed that cobalt occurs primarily as cobaltiferious pyrite (approximately 80% of the contained cobalt) and within other cobalt minerals such as carrollite, and cobaltite (CoAsS). Germanium is also seen to be associated with copper mineralization. In 2011, 50 mostly continuous core samples selected from four drill holes were found to have germanium values ranging from <1 to 83 ppm and averaging 10.7 ppm using sample preparation methods specifically for germanium (compared to a maximum value of 1.15 ppm using a standard analytical method). More recently, values ranging from <1 to 125 ppm and averaging 10.5 ppm were measured in 84 core samples taken from five drill holes from South Reef as part of a Master of Science thesis on the distribution of germanium at South Reef by Alex Jones at the Colorado School of Mines. The average grades obtained from a few samples does not represent the overall germanium grade within the deposit. Further interest in germanium would require additional sampling and metallurgical test work to understand its economic potential. Deposit Type Copper-cobalt-silver-zinc mineralization at Bornite forms disseminations, veins, and massive sulphides in stacked, semi-stratabound bodies closely associated with secondary hydrothermal dolomitization. The cross-cutting nature of the mineralization along with the presence of early pyrite and sphalerite in sedimentary breccia clasts suggest an epigenetic origin that was temporally very close after the deposition of host strata. Re-Os dating supports this interpretation. Data are limited regarding the sources and nature of the copper-rich fluids that formed the Bornite deposit, but they suggest that mineralizing fluids may have formed from the interaction of saline basin fluids with mafic volcanic rocks in the area. An early epigenetic carbonate-hosted Cu-Co model is applicable for exploration targeting in the project area. Exploration Exploration work completed by Kennecott is summarized above. In addition to the extensive drilling completed during the more than 40-year tenure of Kennecott in the district, Kennecott completed widespread surface geochemical sampling, regional and property scale mapping, and numerous geophysical surveys employing a wide variety of techniques. Most of this data has been acquired by us and forms the basis for renewed exploration that targets Bornite-style mineralization in the Bornite carbonate sequence. ​ 2006 NOVAGOLD In 2006, NOVAGOLD contracted Fugro Airborne Surveys to complete a detailed helicopter DIGHEM (frequency-domain EM), magnetic and radiometric survey of the Cosmos Hills. The survey covered a rectangular block approximately 18 km 68 Table of Contents by 49 km which totalled 2,852-line km. The survey was flown at 300 m line spacing with a line direction of N20E. The DIGHEM helicopter survey system produced detailed profile data of magnetics, EM responses and radiometrics (total count, uranium, thorium, and potassium) and was processed into maps of magnetics, discrete EM anomalies, EM apparent resistivity, and radiometric responses. 2010 NOVAGOLD In 2010, in anticipation of completing the NANA Agreement, NANA granted NOVAGOLD permission to begin low level exploration at Bornite. This consisted of re-logging and re-analyzing select drill holes using a NitonTM portable XRF. In addition to the 2010 re-logging effort, NOVAGOLD contracted a consulting geophysicist to compile a unified airborne magnetic map for the Ambler Mining District from Kennecott, Alaska DNR, and NOVAGOLD airborne geophysical surveys. 2011 NOVAGOLD In 2011, NOVAGOLD contracted Zonge International Inc. (“Zonge”) to conduct both dipole-dipole complex resistivity induced polarization (“CRIP”) and natural source audio-magnetotelluric (“NSAMT”) surveys over the northern end of Bornite to develop tools for additional exploration targeting under cover to the north. NSAMT data were acquired along two lines totaling 5.15 line-km; one line is oriented generally north-south through the centre of the survey area and the other line is the southernmost east-west line in the survey area. CRIP data were acquired on five lines: four east-west lines and one north-south line, for a total coverage of 14.1 line-km and 79 collected CRIP stations. The initial objective of the survey was to investigate geological structures and the distribution of sulphides possibly associated with copper mineralization. Results from the paired surveys show that wide-spaced dipole-dipole resistivity is the most effective technique to directly target the mineralization package. Broad, low-resistivity anomalies reflecting pyrite haloes and mineralization appear to define the limits of the fluid package. Well-defined and often very strong chargeability anomalies are also present but appear in part to be masked by phyllitic units which also have strong chargeability signatures. NSAMT shows similar resistivity features as the IP, but these are less well resolved. 2012 NovaCopper Considering the success of the 2011 geophysical program, we contracted Zonge to conduct a major district-wide dipole/dipole IP survey, a down-hole IP radial array survey in the South Reef area, and an extensive physical property characterization study of the various lithologies to better interpret the existing historical geophysical data. Zonge completed 48 line-km of 200 m dipole/dipole IP during 2012, infilling and expanding on the 2011 survey, and stretching across the most prospective part of the outcropping permissive Bornite carbonate sequence. The results show a well-defined low resistivity area associated with mineralization and variable IP signatures attributed both to mineralization and the overlying Beaver Creek phyllite. Numerous target areas occur in the immediate Bornite area with lesser targets occurring in the Aurora Mountain and Pardner Hill areas and in the far east of the survey area. During the 2012 drill program at South Reef, a single drill hole was targeted on a low resistivity area approximately 500 m to 600 m southeast of the South Reef mineralization trend. Although the drill hole intersected some dolomite alteration in the appropriate stratigraphy, no significant sulphides were encountered. In addition to the extensive ground IP survey, Zonge also completed 9 km of down-hole radial IP using an electrode placed in drill hole RC12-0197 to further delineate the trend and potential in and around the South Reef. Extensive physical property data including resistivity, chargeability, specific gravity, and magnetic susceptibility were captured for use in modelling the existing ground IP and gravity surveys, and the airborne EM and magnetic surveys. In addition to geophysical focused exploration, a district wide geologic map was compiled integrating Kennecott’s 1970’s mapping of the Cosmos Hills with selective Trilogy mapping in 2012. 69 Table of Contents 2013 NovaCopper The emphasis of the 2013 program was to further validate and refine the 2012 geologic map of the Cosmos Hills. A deep penetrating soil and vegetation geochemical orientation survey was completed over the South Reef deposit, using various partial leaches and pH methods. The initial, approximately 1 km, test lines suggest a good response for several of the partial leaches of the soils but little response in the vegetative samples. Follow-up is warranted to the north of the deposit into the Ambler Lowlands. 2014 NovaCopper During 2014, exploration work was limited to a re-logging and re-sampling program of historical Kennecott drill core. 2015 NovaCopper As a follow-up to the 2013 field program, a deep penetrating soil and vegetation geochemical survey was extended north of the deposit into the Ambler Lowlands. Trilogy geologists completed a litho-geochemical desktop study and a comprehensive update to the 3D lithology model. 2017 Trilogy The 2017 field program extended the 2013 and 2015 deep penetrating geochemical (“DPG”) soil survey another 500m to the northeast. The 2013 soil line was extended 1,500m to the east to test over the covered projection of the Two Grey Hills carbonate section. The 3D lithology model was updated to incorporate the 2017 drill program results. Trilogy also completed a close spaced ground gravity survey over a 2 km by 4km grid with 100 m station spacing over the resource area and extending northeast over the 2017 drill target area. The complete Bouguer anomaly residual plot (removes a strong decreasing to the northeast regional gradient) shows good correlation with the Lower Reef mineralization that outcrops on surface with the gravity high gradually decreasing down-dip to the northeast. As part of the overall gravity program, Mira Geosciences created a petrophysical model for the Bornite deposit that synthesized the expected gravity response on surface (forward model) for the 2017 gravity stations. This forward model matches very closely with the actual survey data over the deposit area but diverges on the south end where the expected response of gravity low is actually a strong gravity high that may reflect shallow mineralization up-dip along the South Reef trend. Mira also completed a geologically constrained 3D inversion using the 2017 gravity data. Two areas of anomalously high densities (>2.9 g/cc) were identified. The first area extends up to 750m to the east-northeast of RC17-0239, which was one of the more successful holes in 2017 and is coincident with the Iron Mountain structure. The second anomaly is located just above the Anirak contact (Lower Reef) to the west of the 2017 target area and 700m to the north of the closest drill hole (RC-53), which is weakly mineralized along that horizon. This area falls along the northwest-southeast high grade thickness trend. 2018 Trilogy During the 2018 field season, Trilogy Metals carried out additional DPG and a 2D seismic survey at Bornite. In addition, geophysical and geochemical data from Bornite were studied using existing datasets. Soil sampling was completed on the westerly extension of the DPG lines on the northwestern portion of the Bornite deposit. DPG was used to assist with outlining the edges of the deposit as well as to corroborate gravity anomalies defined during the 2017 field season. A 2D seismic survey was completed by HiSeis (3D seismic imaging) in June 2018. This 2D acquisition program was designed to test whether seismic reflection was suitable for the Bornite deposit and to understand the logistics of any future 3D seismic survey over the project area. Two 6 km 2D seismic lines, a dip line and a strike line, were acquired with a total of 792 unique source locations to attempt to image hanging wall and footwall shears; other faults and shears; folding of stratigraphy; internal (within Bornite sequence) phyllite units; facies changes within the dolostones; and direct detection of massive sulphide mineralization; and any alteration associated with mineralization. Acquisition of this 2D 70 Table of Contents dataset used 500 g seismic charges as a means of producing seismic energy. All seismic vibrations were measured on a fully active line of 1,189 geophone receivers which provided up to 6 km of offset on either side of the source using the Aries I seismic acquisition system. Supporting rock property data were acquired from drill core stored in Fairbanks, Alaska. Mira Geosciences completed a 3D inversion model of the 100 m spaced ground gravity data that were collected over the Bornite deposit during the 2017 exploration season. Using geology to constrain the model, three areas of anomalously higher gravity were defined. Unfortunately, none of these intervals were properly tested in 2017 with two holes, those at Anomaly “B” and “C”, ending above the gravity anomalies. Two of the three identified anomalies from the 2017 inversion modelling changed in size and relative orientation with the updated geologic model. Anomaly B, which stretches to the northwest from hole RC17-0238 decreased in extent, likely the result of a thicker-than-previously-modelled Upper Reef carbonate section in RC17-0238. Anomaly C is much broader and less defined, indicating that it may be the result of underestimating the SG in the lithology model. This anomaly remains untested with the failures of drill holes RC17-0242 and RC18-0245 and should be redrilled in the future. Anomaly A is relatively unchanged and remains coincident with the Iron Mountain structure. Holes RC18-0246, RC18-0249, and RC18-0250 tested the southwest edge of the anomaly where it joins the South Reef trend. Hole RC18-0250 suggests that mineralization wanes to the east, though this hole may have just missed mineralization controlled by the Iron Mountain structure. The northeast extent of this anomaly is still considered a viable exploration target. South32 completed a QAQC review, lithogeochemical-alteration assessment, and a vectoring/targeting exercise on downhole geochemical data on the Bornite deposit. The purpose of this exercise was to use downhole analyses to assess the geology, alteration, and mineralogy of the deposit to vector towards mineralization. The Bornite sequence can be classified into three geochemical groups including: 1) very low immobiles; 2) low immobiles; and 3) higher immobiles. The latter was then subdivided into five groups based on Al, Cr, and V concentrations. The very low and low immobile groups are predominately limestones and dolomites (including breccias), whereas increasing Al in higher immobiles represent the increasingly argillaceous/micaceous units (phyllites). High Al samples in the lower Bornite sequence can be discriminated from those in the upper sequence based on high Ni:Cu ratios. In the South Reef area, lithogeochemistry, supported Trilogy Metals’ geologic model, identified the lower, central and upper Bornite sequence units and distinguished many of the logged phyllites from breccias. The results support Trilogy Metals’ interpretation that the Ruby Zone in the Lower Reef is hosted in units corresponding to the South Reef central sequence. 2019 Trilogy In 2019, Trilogy Metals contracted Geotech Ltd. (“Geotech”) of Aurora, Ontario to complete VTEM Plus (versatile time domain electromagnetic) and ZTEM (z-axis tipper electromagnetic) airborne helicopter geophysical surveys over the Cosmos Hills and the Ambler VMS belt. Magnetics were measured using a cesium vapour sensor, while radiometrics was not collected due to snow cover. The VTEM survey was flown along 200 m spaced lines, oriented northwest-southeast over the entire Bornite carbonate sequence north of the Cosmos Arch (which hosts the Bornite deposit), with additional lines at 100 m spacing directly above the Bornite resource. A second set of perpendicular lines (southwest-northeast) were flown at 200 m spacing over just the general Bornite area. Tie lines at ~4,000 m spacing were flown perpendicular to the EM flight lines to provide control for the magnetic survey. The VTEM results from the Bornite sequence are complex and appear to be mostly reflecting bedrock lithologies (the graphitic phyllites). The conductive plates that were modelled are generally coincident with the interpreted phyllite units, as are the apparent anomalies tested by holes RC19-0263 and RC19-0266. ​ 2020 Ambler Metals 71 Table of Contents Trilogy Metals and South32 decided not to proceed with the 2020 exploration program due to the coronavirus pandemic. The Bornite geologic model was updated using the 2019 drill program results. The Irish Centre for Research in Applied Geosciences initiated a machine-learning geochemical modelling project to help define the controls on high-grade copper mineralization. 2021 Ambler Metals During the 2021 field season, the understanding of the Bornite deposit and the potential for additional deposits was advanced with a new interpretation of the carbonate sequence at Bornite and an improved structural understanding of the Cosmos Hills. A specialist in carbonate geology from Laurentian University re-logged two fences/sections of drill holes, east-west and north-south, through the Bornite deposit, to identify, distinguish and correlate lithofacies within the Bornite sequence and to identify and distinguish different types/ages of dolomitization, including, if possible, their relation to mineralization. Turner describes the Bornite sequence as a tectonized normal carbonate slope deposit that consists of calcitic material (lime mud) derived from a nearby shallow-marine source area, interlayered with variable amounts of background terrigenous mud (argillaceous proportion increases with distance downslope). The observed sequence includes massive lime mudstone, thin-bedded argillaceous lime mudstone, lime mudstone centimetrically interbedded with terrigenous mudstone, calcareous siltstone, and limestone-clast slope conglomerates. Brookian deformation strained these argillaceous limestone slope deposits to varying degrees producing phyllites and recrystallized, strained limestones/marbles. Importantly, superimposed on the active limestone slope system is the local presence of dolostone-clast conglomerate. Dolostone clasts are equant and irregular; predominantly dolomudstone (locally with fossil fragments) and are likely derived from subaqueous horst blocks of pre-existing older dolostone and shed into the slope limestone system. The fault scarp(s) that shed dolostone clasts were probably part of a seafloor paleotopographic system that developed during regional extension and associated fault-mediated syn-depositional subsidence. Also initiated in 2021 was structural mapping around Pardner Hill and Aurora Mountain. Initial results indicate: (1) Large carbonate bodies, such as Pardner Hill, Shield Mountain, and probably also Aurora Mountain, are fault klippen in allochthonous contact with the structurally subjacent Anirak schist; (2) Dolostone bodies are typically boudinaged forming metric to hectametric 3-D ellipsoids encased in ductilely deformed phyllites and, in some places, calc-mylonites (limestone protolith); (3) Top-South (to SSW) deformation at a number of outcrops in the Cosmos Hills suggest that this entire structural block may have been juxtaposed southward from the position of the Ambler Lowlands or, potentially, from off the top of the Ambler Highlands (Arctic area) during exhumation that was part of the Brookian orogeny; (4) the fault contact with the overlying Beaver Creek phyllite is likely a low-angle normal fault that cuts out of the Bornite deposit to the southeast where Beaver Creek is in structural contact with Anirak schist. Two diamond drill holes targeting the Bornite copper-hosting carbonate sequence in the Cosmos Hills and Ambler Lowlands were completed during the 2021 field season. Hole ALL21-001 targeted the northeast projection of the Bornite carbonate sequence under cover in the Ambler Lowlands about 7 km east-northeast of Bornite. The second hole, hole RC21-0267 was located at West Bornite, along the Coxcomb Ridge Pardner Hill saddle, 3.5 km west of the Bornite deposit. Hole ALL21-001 intercepted alternating units of limestone clastic breccia, dolostone clastic breccia, limestone and dolostone with textures similar to the Beaver Creek carbonates; alternating intervals of argillaceous phyllite, argillaceous limey phyllite, argillaceous phyllitic limestone, and argillaceous limestone clastic breccias. The phyllitic units host trace pyrite mineralization and have geochemical signatures that are similar to Beaver Creek phyllites. Unfortunately, the hole was lost at 335 m without drilling through the carbonate stratigraphy. Hole RC21-0267 tested the down-dip projection of weakly mineralized dolomitic breccia mapped in the saddle between Coxcomb Ridge and Pardner Hill. The hole intersected argillaceous phyllite (probable Beaver Creek) followed by Bornite sequence: alternating tan phyllitic limestone, tan limey phyllite, argillaceous/carbonaceous phyllitic limestone, limestone 72 Table of Contents clastic breccia, limestone, and argillaceous limestone clastic breccias and dolostone clastic breccia. Trace to locally 1% chalcopyrite, with lesser amounts of sphalerite, and tennantite/tetrahedrite occur through-out a 180 m thickness of dolostone clastic breccia, mostly as disseminations within the breccia matrix and in this carbonate veins. Within this zone a 54.9 m thick interval averages 0.165% Cu starting from 196.5 m. RC21-0267 ended in a quartz phyllite fault zone at 435 m. Ambler Metals (2022) During the 2022 field season, structural mapping around Pardner Hill and Aurora Mountain carried out in 2021 was extended to the south to Cosmos Mountain and to the east to Inerevuk Mountain. In addition, two of seven planned holes were drilled, hole RC22-0268 at Bornite West to follow up the mineralized interval encountered during the 2021 drilling, and the other at Pardner Hill, hole PH22-0180 to test the down-dip potential of the historical Pardner Hill resource to the south. Both holes intersected copper mineralization but intersections were narrower and lower grade compared to nearby holes. Ambler Metals (2023) During 2023, exploration work was limited to a detailed study of the geochemistry results of soil samples collected in the Cosmos Hills and Ambler Lowlands during the 2021 and 2022 field seasons. Ambler Metals (2024) During 2024, exploration work was limited to organizing geospatial data for the Bornite Property, including a new GIS directory structure and digitization of geological maps and structural field data. Drilling From 1957 to 2019, a total of 273 holes targeted the Bornite deposit during 24 different campaigns; 222 surface core holes and 51 underground core holes were drilled, totalling 106,406 m. All of the drill campaigns prior to 2011 were completed by Kennecott or its exploration subsidiary, BCMC, and the drill campaigns since 2011 were completed by NovaGold (2011), NovaCopper (2012 and 2013) or Trilogy. In the summer of 2017, Trilogy Metals initiated eleven holes, but four were abandoned due to drilling problems. The seven remaining drill holes stepped-out to the north for distances between 250 m to 400 m from the previous drill holes; these were distances considered too far to support the estimation of mineral resources at that time. In the summer of 2018, Trilogy Metals conducted a drilling program that included the completion of 12 holes that infilled gaps in previous drilling in the northern, down-dip part of the deposit as well as in the central area between the Ruby Zone and South Reef area. Three additional holes were collared but were abandoned due to drilling problems. In the summer of 2019, Trilogy Metals completed another drilling program comprising eight holes that tested the continuity of the mineralization within the Bornite deposit and two holes that tested exploration targets located about 1 km south and southeast of the deposit. Between 2012 and 2014, Trilogy Metals geologists re-logged and re-sampled legacy drill holes in the Ruby Zone and South Reef area which were previously drilled and only selectively sampled by Kennecott. These assays were used in the estimation of the current mineral resource, except where duplicates of Kennecott samples were collected. In the case of duplicates, the original assay information was given priority in the mineral resource database. In the initial years of drilling at Bornite, Kennecott relied on AX diameter core (30.2 mm diameter), but, as drilling migrated towards deeper targets, a change to BX diameter core (41.3 mm diameter) was implemented to help limit deviation. From 1966 to 1967, drilling activity at Bornite moved underground and EX diameter core (21.5 mm diameter) was implemented to define the Ruby Zone Upper Reef “No.1 Ore Body”. In 1968, drilling activity moved back to the 73 Table of Contents surface and from 1968 to 1972, BX diameter core was most commonly drilled. In later years, core size increased to NX (54.0 mm diameter) and finally, in 2011, core size increased to NQ (47.6 mm diameter) and HQ (63.5 mm diameter). Over the years, progressively larger diameter drill rods have been used in an effort to minimize drill hole deviations. There is limited information with respect to the specific drill core handling procedures used by BCMC/Kennecott. All drill data collected during 1957 to 1997 were logged on paper drill logs with copies were stored in the Kennecott office in Salt Lake City, Utah. Electronic, scanned copies of the paper logs are held by Trilogy and stored in the Fairbanks field office. Drill core was sawed or split in half with a splitter, half was submitted to various assay labratories and the remainder was stored in the Kennecott/BCMC core storage facility at the Bornite deposit. In 1995, Kennecott converted the drill assay data, geologic core logs and the down-hole collar survey data into an electronic format. In 2009, NOVAGOLD geologists verified the geologic data from the original paper logs against the Kennecott electronic format and then merged the data into a MicrosoftTM SQL database. Sampling of drill core by Kennecott/BCMC focused primarily on the moderate-to-high grade mineralized zones. Intervals of visible sulphide mineralization containing roughly >0.5% to 1% Cu were selected for analysis by Union Assay Office Inc. of Salt Lake City, Utah. This approach left numerous intervals containing weak to moderate copper mineralization, un-sampled in the historical drill core. During the 2012 exploration program, we began sampling a portion of this remaining drill core in select holes in the South Reef area. Trilogy extended this sampling program to the Ruby Zone in 2013 and 2014. Throughout our tenure at Bornite, the following core handling procedures have been implemented (including programs conducted by NOVAGOLD and NovaCopper). Core is slung by helicopter or transported by truck or all-terrain vehicle from the drill rig to the core-logging facility. Upon delivery, geologists and geotechnicians open and inspect the core boxes for any irregularities. They first mark the location of each drilling block on the core box, and then convert footages on the blocks into metric equivalents. Geo-technicians or geologists measure the intervals (or from/to) for each box of core and include this information, together with the drill hole ID and box number, on a metal tag stapled to the end of each box. Geo-technicians then measure the core to calculate percent recovery and rock quality designation (“RQD”). RQD is the sum of the total length of all pieces of core in a run over 12 cm. The total length of core in each run is measured and compared to the corresponding run length to determine percent recovery. Core is then logged with lithology and visual alteration features captured on observed interval breaks. Mineralization data, including sulphide species (recorded as percent), sulphide type (recorded as a relative amount) and gangue and vein mineralogy are collected for each sample interval with an average interval of approximately 2 m. Structural data is collected as point data. Geologists then mark sample intervals to indicate each lithology or other geologically appropriate intervals. Sample intervals of core are typically between 1 m and 3 m in length but are not to exceed 3 m long. Occasionally, if warranted by the need for better resolution of geology or mineralization, smaller sample intervals have been used. Geologists staple sample tags on the core boxes at the start of each sample interval and mark the core itself with a wax pencil to designate sample intervals. This sampling approach is considered sound and appropriate for this style of mineralization and alteration. Drill core is digitally photographed prior to sampling. Drill core is cut in half using diamond core saws. Specific attention to core orientation is maintained during core sawing to ensure that representative samples are obtained. One-half of the core is retained in the core box for storage on site, or at our Fairbanks warehouse, and the other half is bagged and labeled for analysis. Samples are selected for specific gravity measurements. In 2013 and 2014, 33 historical drill holes and 37 historical drill holes, respectively, in the Ruby Zone were re-logged, re-sampled and re-assayed as these holes had previously only been selectively sampled by Kennecott. Entire holes were re-logged using Trilogy protocols discussed above. Samples were submitted either as half-core, where previously sampled, or whole core where un-sampled (to ensure that a sufficient volume of material was provided for analysis). Sample intervals were matched to historical intervals whenever possible or selected to reflect Trilogy sampling procedures described above. The objectives of the re-assay/re-logging program were threefold: 1) to implement a QAQC program on intervals previously sampled by Kennecott in order to confirm the validity of its results; 2) to identify additional lower grade (0.2%-0.5% Cu), which was not previously sampled; and 3) to provide additional multi-element ICP data to assist in the geologic interpretation of the deposit. Preliminary geotechnical data was collected from drill core such as RQD and limited hydrogeology data has been obtained which is sufficient to support early-stage resource estimation. The Wood QP is not aware of any drilling, 74 Table of Contents sampling or recovery factors that could materially impact the accuracy and reliability of the copper results supporting the mineral resource estimate other than what is described in the sections that follow. Sampling, Analysis and Data Verification There is limited documentation available describing the sample preparation, security, and analysis of drill core samples with mixed in QAQC check assays. Gold and silver were likely analyzed by fire assay off site. Between 2012 and 2014, Trilogy Metals completed a re-assay and re-sampling program of the historical drill holes. As a result, 67% of the historical hole assay values are now supported by a current and documented QAQC program The drill core sampling procedures are described above. After the drill core was sawed in half, one half was retained for future reference and the other half was sent to ALS Minerals (formerly ALS Chemex) in Vancouver, British Columbia for analyses. Core samples were shipped from the Bornite camp when backhaul capacity was available on the chartered aircraft; this was generally five to six days a week. Rice bags, containing two to four individual poly-bagged core samples, were marked and labeled with the ALS Minerals address, project name (Bornite), drill hole number, bag number, and the enclosed sample numbers. Rice bags were secured with a pre-numbered plastic security tie, assembled into loads for transport by chartered flights on a commercial airline to Fairbanks, Alaska, and delivered directly to the ALS Minerals preparation facility by a contracted expeditor. Control samples were also inserted into these shipments at the rate of one standard, one blank and one duplicate per 17 core samples. Samples were logged into a tracking system on arrival at ALS Minerals and weighed. Samples were then crushed, dried, and a 250 g split was pulverized to greater than 85% passing 75 μm. Security measures taken during historical Kennecott and BCMC programs are not known to Trilogy Metals; however, Trilogy Metals is not aware of any reason to suspect that any of these samples have been tampered with. The 2011 to 2019 samples were either in the custody of NOVAGOLD or Trilogy Metals personnel, or the assay laboratories at all times and the chain of custody of the samples is well documented. Copper and cobalt data were derived using a 48-element suite assayed by inductively coupled plasma-mass spectrometry (“ICP-MS”) and atomic emission spectroscopy (“ICP-AES”) methodologies, following a four-acid digestion. The lower detection limits for copper and cobalt are 0.2ppm and 0.1 ppm, respectively. The upper limits were 10,000ppm. Over limit (>1.0%) copper and cobalt analyses were completed by atomic absorption (“AA”), following a four-acid digestion. In 2011 and 2012, gold assays were determined using fire analysis followed by an atomic absorption spectroscopy (“AAS”) finish. Gold was not analyzed in 2013 or 2014. The lower detection limit was 0.005 ppm Au; the upper limit was 10 ppm Au. ALS Minerals has attained International Organization for Standardization (“ISO”) 9001:2000 registration. In addition, the ALS Minerals laboratory in Vancouver is accredited to ISO 17025 by Standards Council of Canada for a number of specific test procedures including fire assay of gold by AA, ICP and gravimetric finish, multi-element ICP and AA assays for silver, copper, lead and zinc. Trilogy has no relationship with any of the primary or check assay labs used on the Bornite Project. In 2012, 2013, 2014, and 2017 through to 2019, Trilogy Metals staff performed continuous validation of the drill data during the logging process and after the field program was complete. Trilogy Metals also retained independent consultant GeoSpark Consulting Inc. (“GeoSpark”) to import digital drill data to the master database and conduct QAQC checks upon import; conduct a QAQC review of paired historical assays and Trilogy Metals 2012, 2013 and 2014 re-assays; monitor an independent check assay program for the 2012, 2013 and 2014 campaigns; and generate a QAQC report for each of the drilling campaigns conducted in 2012, 2013, 2014, 2017, 2018 and 2019, including a 2017 review of the cobalt data. QAQC monitoring by GeoSpark included assessment laboratory precision and accuracy using assay results from certified reference standards, blanks and duplicates inserted into the sample stream by Trilogy Metals personnel. Wood’s geology and resource QP visited the Bornite property from August 29 to September 8, 2022. During the visit, he reviewed drill core, measured drill collars with a handheld GPS unit, visited the historical trench area and viewed the 75 Table of Contents deposit area by helicopter. Wood’s geology and resource QP also measured five surface drill collars with a handheld GPS unit. Out of five drill collars, one drill collar was off more than 40 m when compared to the collar database. After further investigation, Ambler Metals identified seven drill collars in the database with planned coordinates, rather than the surveyed coordinates. The QP has reviewed the metallurgical testwork reports, the analytical procedures, qualification of the laboratory, and presentation of the test results and considers all to have followed industry accepted practice. Inspection of the historical drill hole data has revealed some issues with collar, down hole survey and assay results. There are 183 historical holes representing 46% of the total drilled metres in the Bornite database 177 of which are in the Ruby Zone and six of which are in the South Reef area. There are no significant concerns with the current collar survey records.Issues identified are manageable by the significant number of drilling and sampling that has been undertaken, and restriction of the resource classification to the Inferred category. Wood’s geology and resource QP’s review of the database transcription error checks is considered adequate and provides sufficient support for the database to be judged as acceptably error free. In the opinion of the QP the metallurgical data is adequate for the purposes used in the NI 43-101 Bornite Report and the S-K 1300 Bornite Report. Mineral Processing and Metallurgical Testing In 1961, Kennecott collected 32 coarse reject samples from five drill holes intersecting the Bornite deposit (RC-34, RC-54, RC-60, RC-61, and RC-65) to support preliminary metallurgical test work conducted at KRC. Samples targeted high-grade (>10%) copper mineralization from the Ruby Zone Upper Reef (“No. 1 Ore Body”) (BCMC, 1961). Locked-cycle laboratory test work suggested that 97.64% of the copper was recoverable in a concentrate assaying 43.90% Cu. Fine-grinding to 5% passing +200-mesh was required to obtain the liberation of copper minerals from pyrite necessary for such a high recovery. Mineralogical test work on the composite sample showed high-grade mineralization of the Ruby Zone Upper Reef is dominated by bornite with subordinate chalcocite and chalcopyrite. A total of four metallurgical test work programs have been conducted on materials from the Bornite Property under the supervision of Trilogy Metals. In 2012, Trilogy Metals contracted ALS Metallurgy to conduct preliminary sample characterization and flotation test work on mineralized samples collected from the South Reef area. To the extent known, the samples are representative of the styles and types of mineralization present in the South Reef area. The program at ALS Metallurgy was based on traditional grinding and flotation test work aimed at producing saleable copper concentrates. The test work continued into 2013. In 2017, Trilogy Metals contracted SGS to conduct detailed metallurgical test work on a series of samples that represent the lower grade mineralization within the constraining pit shell. This work followed the preliminary flowsheet and process options outlined in the 2012/2013 test work. This test work continued into 2018. Additional metallurgical testing was conducted by ALS Metallurgy in 2018/2019 and again in 2020/2021 which followed on from the process development of the earlier test work. Metallurgical test work to date indicates that the Bornite mineralization can be treated using standard grinding and flotation methods to produce clean copper concentrates with good results being obtained. The copper concentrate that would be produced is considered in general terms a clean concentrate, and it is unlikely that penalties would be imposed as no significant amounts of deleterious elements are contained in the concentrate. Mineral Resource Estimates The mineral resources were prepared in accordance with the standards and definitions of S-K 1300. The QP considers the sample preparation, security and analytical procedures adequate to support an Inferred mineral resource. 76 Table of Contents The Bornite database comprises a total of 273 diamond drill (core) holes totalling 106,406 m; 203 holes target the Ruby Zone to the west and 58 holes target the South Reef area to the east. The remaining 12 holes in the database are exploratory in nature and test for satellite mineralization proximal to the Bornite deposit or represent holes that encountered problems and were therefore abandoned. A total of 242 drill holes are used in the mineral resource estimate contains a total of 39,740 samples that were analyzed for copper content and 34,177 that were analyzed for cobalt content. Most holes drilled by Trilogy, plus a few select historical holes drilled by Kennecott, contain additional analyses for elements such as zinc, lead, gold, silver, and cobalt. At this time, only copper has reasonable prospectus for eventual economic extraction. During the 2012, 2013 and 2014 field seasons, Trilogy collected samples from drill hole intervals that were not previously sampled. It is assumed that Kennecott did not sample these intervals because, visually, they did not exhibit the presence of high-grade copper mineralization (amenable to underground mining). In previous mineral resource estimates, these un-sampled intervals were assigned a default grade of 0% Cu. At this current stage, the majority of the core drilled by Kennecott has been sampled and analyzed for copper content and are included in the database. The sampling and assaying for cobalt is less extensive. Where assay data are not available, these intervals are assigned a zero grade for cobalt (0% Co) when the host rocks are phyllite, or they are left blank when the host rocks are carbonates. Individual sample intervals range from 3 cm to 39.58 m long and average 2.09 m. Drill hole spacing at the Ruby Zone varies from approximately 10 m to 20 m for underground holes and 50 m to 100 m or more for holes drilled from surface. All holes testing the South Reef area are collared from surface and typically intersect mineralization at approximately 100 m to 200 m spacing. Specific gravity (“SG”) measurements were conducted on 7,476 samples in the database and range from a minimum of 2.12 to a maximum of 5.20 and average 2.89. The distribution of SG data is considered sufficient to support resource estimation. The geologic model interpreted for the Bornite deposit consists primarily of a series of inter-bedded carbonate and phyllitic rocks that dip gently to the north and overlay a quartz-phyllite footwall. The geologic model comprises 18 individual phyllite domains and 16 separate carbonate domains plus a series of separate domains representing the hanging wall (Beaver Creek phyllite), the footwall (quartz-phyllite Anirak schist), and the overlying overburden. Some of the phyllite and carbonate units are continuous across the entire deposit area and others pinch out and are more localized. The parts of the deposit with the highest grades occur within areas where semi-massive and massive sulphides are present. The density of drilling is insufficient in most areas to allow for the interpretation of these massive sulphide domains, and a probability shell approach is used to identify areas where higher grade mineralization is likely to occur. Two probability shells were generated: one at a threshold of 2% Cu and another at a threshold of 0.2% Cu. The 2% Cu shell generally correlates with the presence of massive and semi-massive zones of bornite and chalcopyrite mineralization, and the 0.2% Cu shell correlates with the visual presence of chalcopyrite mineralization. Cobalt mineralization is strongly associated with both sets of copper mineralization. The higher grade shell occurs mainly in the South Reef area and is based primarily on visual observations of the distribution of sample data suggesting that a relatively continuous zone of higher grade copper mineralization occurs above a threshold grade of 2% Cu. Approximately 90% of the sample data in the South Reef area is below 2% Cu and 10% of the data is greater than 2% Cu. A relatively small (>2%) copper probability shell is also generated in the Upper Reef area of the Ruby Zone. Approximately one half of the samples in the carbonate domains have copper grades above the lower grade threshold of 0.2% copper. This limit roughly segregates areas of mineralized versus unmineralized rocks and is still below the anticipated cut-off grade of the mineral resource, ensuring that sufficient internal dilution is retained in the mineral resource model. There are also areas where the phyllite domains contain appreciable copper grades (above the 0.2% Cu threshold), but these tend to be rare and localized occurrences. 77 Table of Contents Indicator values are assigned to 2 m composites at the grade thresholds, and indicator variograms are produced. Probability values are estimated in model blocks using ordinary kriging; the vertical range and locations are controlled dynamically using elevations relative to the trend planes described previously. A series of shells are generated at varying probability thresholds and are then compared to the distribution of the underlying sample data. The higher grade shell represents areas where there is greater than a 30% probability that the grade will be more than 2% Cu. The lower grade shell envelopes areas where there is a greater than 50% probability that the grade will exceed 0.2% Cu. At this stage of project evaluation, copper is the only economic contributor at Bornite. There is potential for reasonable prospects of eventual economic extraction for cobalt with additional drill information and metallurgical test work to establish the appropriate process options available to produce marketable pyrite-cobalt concentrate. Currently there is insufficient information to identify reasonable process method for economic recovery of cobalt or a market for the pyrite-cobalt concentrate. The Bornite deposit comprises several zones of relatively continuous moderate- to high-grade copper mineralization that extends from surface to depths of more than 800 m below surface. The deposit is amenable to either open pit or underground mining methods. Underground mining assumes a combination of the sub-level stoping method for South Reef and cut-and-fill method for Ruby Zone with assumed mining cost $65.00/t and $90.00/t mined, respectively. Using these parameters an open pit marginal cut-off grade of 0.5% Cu and an underground break-even cut-off grade of 1.45% Cu for South Reef and 1.79% Cu for Ruby Zone were determined. The underground mining shape for Ruby Zone is based on a 1.79% Cu grade shell while the underground mining shape for South Reef utilizes a mineable stope optimizer based on 1.45% Cu. Underground development material not included within the mineable stope shape that is mined to gain access to the stopes and is above a marginal cut-off grade of 0.7% Cu can be selectively handled and stored in a low-grade stockpile to be processed at the end of the mine life. This material is included in the mineral resource estimate as a separate line item. The Wood QP considers industry consensus on a long-term price forecast on production schedules and cash flows of $4.20/lb Cu is reasonable over the life of the expected mine plan. It is in accordance with industry-accepted practice to use higher metal prices for the mineral resource estimates than the consensus price used for production schedules and cash flows. The copper price forecast of $4.20/lb was increased by approximately 10% to provide the mineral resource estimate copper price assumption of $4.60/lb. This ensures that the mineral resources in the S-K 1300 Bornite Report production schedule are a subset of the total mineral resources. The operating costs accuracy is ±50% with a contingency of less than 25%. Mineral Resources are classified in accordance with S-K 1300. The Wood QP reviewed and performed validation checks on the mineral resource model and based on the results prepared a revised mineral resource statement that is summarized in Table 1. The mineral resource estimates are based on a combination of open pit and underground mining methods and a copper price of $4.60/lb. Mineral resources amenable to open pit methods are constrained within a pit shell above a marginal cut-off grade of 0.5% Cu and those amenable by underground methods are constrained within a grade shell defined by breakeven cut-off grades of 1.45% Cu for South Reef and of 1.79% Cu for Ruby Zone. A portion of the in-pit mineral resource is well above the 1.79% Cu cut-off and would be amenable to underground mining methods providing flexibility on how to develop the deposit (Table 2). 78 Table of Contents Table 1 – Bornite Mineral Resources Statement as at November 30, 2024 Class Type/Area Cut-off (Cu %) Tonnes (Mt) Average Grade Cu (%) Contained Metal Cu (Mlb) Inferred In-Pit 0.50 170.4 1.15 4,303 ​ Outside-Pit South Reef 1.45 27.5 2.78 1,687 ​ Outside-Pit Ruby Zone 1.79 10.4 2.28 521 ​ Underground Development 0.70 0.7 0.98 16 Total Inferred – 100% ​ ​ 208.9 1.42 6,527 Total Inferred – 50% Attributable Interest ​ ​ 104.45 1.42 3,263.5 Notes: 1. Wood is the third-party firm responsible for preparing the mineral resource estimate. 2. Mineral resources are prepared in accordance with S-K 1300 definitions. Mineral resources are exclusive of mineral reserves. There have been no mineral reserves estimated on the Bornite Property. 3. The assessment is preliminary in nature, it includes Inferred mineral resources that are considered too speculative geologically to have modifying factors applied to them that would enable them to be categorized as mineral reserves, and there is no certainty that this economic assessment will be realized. 4. Mineral resources are reported in place (point of reference). 5. Mineral resources are constrained by: an open pit shell at a cut-off grade of 0.50% Cu, with an average pit slope of 43 degrees; and underground mining shapes assuming cut-and-fill mining method based on a 1.79% Cu grade shell for Ruby Zone and an optimized underground mineable stope shape assuming sublevel stoping mine method based on a break-even cut-off grade of 1.45% for South Reef. The cut-off grades assume a $4.60/lb Cu price over the expected 17-year LOM, process recovery of 90.47%, process cost of $21.00/t processed, treatment, refining, sales cost of $0.78/lb Cu in concentrate, road use cost of $8.04/t processed, and 2% NSR royalty. For the open pit, costs include mining costs of $3.34/t mined and G&A cost of $4.30/t processed. For mining at South Reef, costs include mining costs of $65.00/t mined and G&A cost of $14.50/t processed. For mining at Ruby Zone, costs include mining costs of $90.00/t mined and G&A cost of $14.50/t processed. The long-term metal price forecast used a combination of information derived from 22 financial institutions, from pricing used in technical reports filed with Canadian regulatory authorities over the previous 12-month period from the effective date of the mineral resource estimate, from pricing reported by major mining companies in public filings such as annual reports, historical average pricing. 6. Underground development material uses a marginal cut-off of 0.70% Cu where the mining costs are excluded. 7. Figures may not sum due to rounding. 8. The mineral resource estimates are shown on a 100% ownership basis, of which Trilogy Metals’ share is 50%. ​ 79 Table of Contents Table 2 – Portions of South Reef Mineral Resource Amenable to Underground Mining Class Type/Area Cut-off (Cu %) Tonnes (Mt) Average Grade (Cu %) Contained Cu (Mlb) Inferred In-Pit South Reef 1 1.45 14.2 2.80 876 ​ Outside-Pit South Reef 2 1.45 27.5 2.78 1,687 Inferred Total South Reef ​ 41.7 2.79 2,563 Notes: 1. The 1.45% Cu break-even cut-off assumes sublevel stoping mine method. The cut-off grades assume a $4.60/lb Cu price, process recovery of 90.47%, process cost of $21.00/t processed, mining costs of $65.00/t mined and G&A cost of $14.50/t processed, treatment, refining, sales cost of $0.78/lb Cu in concentrate, road use cost of $8.04/t processed, and 2% NSR royalty. 2. Subset of the mineral resource using a higher cut-off to what was used in Table 1 and is not additive to the in-pit mineral resource reported in Table 1. 3. Restatement of the mineral resources outside of the pit as reported in Table 1 and is not additive to Table 1. 4. Trilogy’s attributable interest is 50% of the tonnage and contained metals. ​ Some of the in-pit mineral resources are of sufficiently high grade to allow mining by underground mining methods which allows flexibility on how they could eventually be extracted. Additional to what are described elsewhere in the S-K 1300 Bornite Report that could affect the mineral resource estimate include: ● Unrecognized complexity and other changes to the interpretation of the geological model and grade shell ● Mineral resource estimation involves judgement and interpretations by a QP. Different QPs could come up with different results ● Uncertainties regarding bias in the higher-grade copper ● Unrecognized metallurgical variability ● Uncertainties in the quantities of water underground that may need to be managed ● Uncertainty in government approval for developing road access to site Mining Operations The Bornite mine consists of an underground operation to exploit the higher-grade South Reef. The underground mine will focus on South Reef using sublevel stoping. Stope shape optimizations were run to generate production stopes using cut-off grades determined from preliminary cost modelling, stope optimization parameters and process recoveries. Throughput and cut-off grade were optimized resulting in 6,000 t/d and 1.6% Cu cut-off, respectively. South Reef will be accessed from surface via twin declines, one for the material handling system and the second for mobile equipment and personnel access. It is expected that an exploration decline will have been developed prior to the start of underground development allowing access to the deposit quicker. The material handling system utilizes 63-tonne diesel trucks to haul development mineralized material and waste and a conveyor system to transport production mineralized material to the run-of-mine (“ROM”) pad on surface. Underground development will require two years pre-production and a year of ramp up before reaching 6,000 t/d production. The Bornite life-of-mine (“LOM”) is 17 years. 80 Table of Contents A subset of the mineral resources within the LOM plan is summarized in Table 3. Table 3 – Subset of the Bornite Mineral Resource Estimate within the Initial Assessment Mine Plan Confidence Category Tonnes (Mt) Average Grade (Cu %) Contained Cu (Mlb) Inferred 36.9 2.61 2,125 Notes: 1. Mineral resources within the mine plan were estimated using sublevel stoping underground mining method and includes variable dilution and a mining recovery of 95%. 2. The assessment is preliminary in nature, it includes inferred mineral resources that are considered too speculative geologically to have modifying factors applied to them that would enable them to be categorized as mineral reserves and there is no certainty that this economic assessment will be realized. 3. Input assumptions used to determine mineable stope shapes include a copper price of $4.20/lb, mine operating cost of $73.29/t, process operating cost of $19.84/t, G&A and surface costs of $9.64/t, haulage and road use costs of $28.78/t, closure and water treatment costs of $1.26/t, shipping, treatment, refining and selling costs of $0.78/lb Cu, process recovery of 90%, and NSR royalty of 2%. 4. Production stope cut-off of 1.6% Cu and development cut-off 0.7% Cu.The production stope cut-off input assumptions include a copper price of $4.20/lb, mine operating cost of $44.08/t, process operating cost of $24.82/t, G&A and surface cost of $17.3/t, and sustaining costs of $8.52/t, road use costs of $14.4/t, shipping, treatment, refining and selling costs of $0.78/lb Cu, process recovery of 90.89% and average NSR royalty of 2.25%. Forecast copper prices used for mine planning and cash flow analysis are as of September 6, 2024. The forecast price of $4.20 reflects the average forecasted price from 18 financial institutions. 5. Trilogy’s attributable interest is 50% of the tonnage and contained metal. ​ Processing and Recovery Operations The recovery test work conducted in the ALS Metallurgy test work program KM3621 was not optimized and is preliminary in terms of results. The SGS flotation test work and the balance of ALS Metallurgy test work, by comparison, is more exhaustive in terms of process optimization, and these results show higher copper recoveries and better overall results. ​ Bornite material will be processed in the Arctic process plant that has currently been designed to a feasibility study level. The process plant will process 10,000 t/d of material on a two week on, one week off campaign basis. The process plant will operate at an overall availability of 64%, processing an annual average of 2,215,000 tonnes of mineralized material to produce a copper concentrate. Modifications to the Arctic flowsheet to allow the processing of Bornite material at the end of the Arctic LOM include: ● decommissioning the talc, zinc and lead flotation circuits as these are not required to process Bornite material. ● incorporating some of the zinc circuit flotation and dewatering equipment in the copper flotation and dewatering circuit which is anticipated to handle higher copper loadings. ● a new regrind mill will be required to operate in parallel to the existing copper and zinc regrind mills. A new tailings filtration plant will dewater up to 50% of the plant tailings for paste backfill purposes. Filtered tailings will be transported by dual tractor trailer from the Arctic plant to the Bornite paste backfill plant. Power consumption will be less than the total output capacity currently required for the Arctic process plant. 81 Table of Contents Infrastructure, Permitting and Compliance Activities Surface infrastructure is limited at the Bornite site as the Bornite Project will leverage off of existing infrastructure at Arctic once Arctic mineral reserves have been exhausted. Onsite infrastructure and services required to support the Bornite Project include mining facilities including a paste fill plant, waste transfer pad, ROM stockpile, topsoil stockpile, underground portal, power plant, fuel storage, upgraded Ruby Creek section, dewatering wells, water treatment pond, contact and non-contact diversions/ditches. It is assumed that the Arctic camp will be sufficient to accommodate Bornite personnel. Access to site will be from the north, along the south route from the AAP road and from the south from the Dahl Creek airport. A waste transfer pad with capacity of 40,000 tonnes will temporarily store waste and low grade mineralized material from underground and will be hauled to the Arctic waste rock facility for long term storage. Low-grade mineralized material will be processed at the end of mine life. A ROM stockpile with a capacity of 30,000 tonnes equating to five days of production will store mineralized material and serve as a loading point for haulage to the Arctic mill by the over-the-road (“OTR”) truck fleet. Tailings produced from processing the mineralized material from Bornite at the Arctic mill, will be stored in an expanded Arctic tailings storage facility (“TSF”) and within the Arctic pit. The existing TSF will be expanded to hold the additional 16 Mm 3 while the pit will store 2.5 Mm 3 with the possibility of storing more if required. It is assumed that approximately 50% of the tailings would be sent to the filter press at the Arctic mill to be used to produce paste backfill and is backhauled to the Bornite site. A portal diesel power plant comprising of six diesel gensets will provide power for peak site demand of 13.3 MWe. Perimeter dewatering wells are planned to limit the inflow of water into the underground mine. This water will be conveyed back into Ruby Creek. The upgraded Ruby Creek section and Ruby Creek valley dewatering wells are intended to disconnect flow in Ruby Creek from the underlying groundwater system and reduce infiltration into the mine. Diversion ditches around site will intercept any water runoff before it becomes contact water. Contact water will be treated before release into the environment. Capital and Operating Costs A Class 5 capital cost estimate was prepared in accordance with AACE International Guidelines Practice No. 47R-11 with an expected accuracy of ±50% and a contingency of 14.4% overall. All costs are expressed in fourth-quarter 2024 US dollars. The Bornite Project’s initial capital cost, as summarized in Table 4 is $503.4 million, including indirect costs of $80.6 million and contingency of $72.5 million. A sustaining capital of $363.1 million considers equipment replacement costs and pipeline and ditch construction for water management and electrical. The total Bornite Project capital, inclusive of initial and sustaining costs is estimated at $866.5 million. 82 Table of Contents Table 4 – Summary of Capital Cost Estimate WBS Description Initial Capital ($M) Sustaining Capital ($M) Total Capital ($M) 1000 Mining 214.9 300.6 515.5 2000 Crushing - - - 3000 Process 28.6 - 28.6 4000 Tailings 10.4 - 10.4 5000 Onsite Infrastructure 85.3 20.7 106.0 6000 Offsite Infrastructure 1.7 - 1.7 Subtotal ​ 340.8 321.3 662.1 7000 Indirect Costs 80.6 4.1 84.7 9000 Owners’ Costs 9.5 1.2 10.7 8000 Provisions/Contingency 72.5 36.5 109.0 Total ​ 503.4 363.1 866.5 Note: 1. Figures may not sum due to rounding. ​ Operating Costs Total operating costs over the LOM have been estimated at $3,651.6 million with a breakdown summarized in Table 5. The operating costs accuracy is ±50% with a contingency of less than 25%. Table 5 – Total Operating Costs over LOM Cost Area LOM Cost ($M) Avg. Unit Cost of Mineralized Material Processed ($/t) Underground Mining 1,392.5 37.74 OTR Haulage 197.3 5.35 Process 915.8 24.82 AAP Road 528.7 14.33 G&A 495.2 13.42 Water Management 105.8 2.87 Surface Operations Cost 16.4 0.44 Total 3,651.6 98.97 Note: 1. G&A = general and administrative 2. Figures may not sum due to rounding. ​ Financial Model The results of the economic analysis in the Bornite Study represents forward-looking information that is subject to a number of known and unknown risks, uncertainties, and other factors that may cause actual results to differ materially from those presented here. Forward-looking information includes mineral resource estimates in the Bornite Study mine plan and the cash flows derived from them, forecast copper prices used, capital and operating cost estimates, estimated copper production, and payback period. Actual results may vary from the forward-looking information with the mineral resource estimates, costs, copper prices, metallurgical recoveries, and taxes being different from what was assumed in the Bornite Study. 83 Table of Contents The assessment is preliminary in nature, it includes inferred mineral resources that are considered too speculative geologically to have modifying factors applied to them that would enable them to be categorized as mineral reserves, and there is no certainty that this economic assessment will be realized. The Bornite Study has been evaluated using a discounted cash flow (“DCF”) analysis. Cash inflows consist of annual revenue projections for the mine. Cash outflows such as capital, pre-production mining costs, operating costs, taxes, and royalties, are subtracted from the inflows to arrive at the annual cash flow projections. Cash flows are taken to occur at the end of each period. The after-tax evaluation of the Bornite Project under the assumptions used in the Bornite Study generates positive results. Before-tax and after-tax financial results are presented in Table 6. The financial analysis is presented on a 100% basis on which Trilogy Metals has a 50% attributable interest. The financial model on which the analysis is based includes 100% inferred mineral resources. The results of the economic analysis excluding inferred mineral resources would not be economically viable. The Bornite Project is most sensitive to changes in copper selling price and copper feed grade, followed by changes to operating cots and total capital costs. Table 6 – Financial Results Description Unit Value Pre-Tax Valuation Indicators ​ ​ Undiscounted Cumulative Cash Flow $M 1,582.5 NPV @ 8% $M 552.1 Payback Period (from start of operations) years 4.0 IRR Before Tax % 23.6 Post-Tax Valuation Indicators ​ ​ Undiscounted Cumulative Cash Flow $M 1,218.8 NPV @ 8% $M 393.9 Payback Period (from start of operations) years 4.4 IRR After Tax % 20.0 Note: NPV = net present value; IRR = internal rate of return Exploration, Development, and Production Based on the mineral resource estimates and existing metallurgical test work presented in the Bornite Study, the QPs recommend the following: developing an advanced exploration decline to access South Reef for further drilling, hydrogeology, geotechnical and rock mechanics work, metallurgical test work, investigations around re-purposing the Arctic process plant to receive Bornite mineralized material, tailings studies considering additional locations and technologies, a hydrological program, geochemistry assessments, a site water and load balance (water quality predictions) and water treatment needs, and environmental baseline studies with estimated costs totaling $172.4 million. Exploration Potential Outcropping exposures of the mineralization-hosting carbonate stratigraphy along with large areas of dolomite alteration occur over approximately 18 km of strike along the northern flank of the Cosmos Hills. Historical exploration drilling focused solely on outcropping mineralization and subsurface extensions at the Bornite, Aurora Mountain, and Pardner Hill areas. Much of the carbonate belt has still yet to be evaluated. In addition, airborne geophysics completed 84 Table of Contents in 2006 show the Bornite carbonate sequence and the bounding stratigraphy dip to the north under the Ambler Lowlands toward the Ambler Schist Belt. This opens a large area to explore for deposits beneath the till and recent sediments that occupy the lowlands. Exploration by Kennecott and Trilogy Metals has used a variety of methodologies. In 1996, Kennecott completed an initial gravity survey of the Ambler Lowlands showing significant gravimetric anomalies that may indicate structural dislocations and potential alteration and mineralization. In 2011, Trilogy Metals investigated both deep IP and NSAMT geophysical techniques. Results from the 2011 program led to a 2012 district-wide, 200 m dipole-dipole, deep-penetrating IP survey. Along with extensive physical property data captured for all lithologies, airborne EM and magnetic data, the IP data was used to develop a comprehensive geophysical model of the district to support future exploration targeting. In 2017, Trilogy Metals conducted a more detailed gravity survey that delineated significant north-northeast to northeast oriented structures which appear in part to control local basin morphology and mineralization. Geochemical methods include conventional and DPG and lithogeochemical vectoring. Test lines using DPG methods with various selective partial leaches of metals proved effective in recognizing margins of South Reef mineralization at significant depths under cover. A recent analysis of the extensive ICP trace element data set at Bornite demonstrates some significant alteration vectors including iron content of various hydrothermal dolomites. Simple XRF analysis of dolomites in the field might prove effective in vectoring toward Fe-poor mineralized dolomite sections. A better understanding of the basin development and its structural framework is critical to the exploration of Bornite-style systems. Dating of mineralization in the Ambler Mining District suggests that the Ambler schist belt that hosts the Arctic deposit and the Bornite carbonate-hosted mineralization are close to contemporaneous. However, some textural and metamorphic observations suggest a possible Jura-Cretaceous or younger age for Bornite and as such, mineralization at Bornite is suspected to slightly post-date host stratigraphy. This early and extensive syngenetic/early epigenetic signature, along with the overall fluid chemistry of the system investigated by early workers, such as Hitzman (1983 and 1986), point to large saline basin-generated fluid transport as the mechanism controlling the metallogeny of the Ambler Mining District. Importantly, similar metallogenies related to saline, basin-generated fluids and their associated deposits form some of the largest copper districts in the world. A portion of the Ruby Zone deposit is near surface that is amenable to open pit mining. This material was not included in the mine plan to limit surface capital related to a required expansion of the tailings facility at Arctic, but pending further study work, could be included in a future mine plan. A portion of the Ruby Zone deposit is amenable to underground mining. A preliminary design included 6.3 Mt at 2.38% Cu utilizing a cut-and-fill mining method, but this was removed to improve project economics by limiting sustaining capital and the required expansion of the tailings facility at Arctic. Depending on copper price and geological interpretation of the resource, sublevel stoping could be an appropriate mining method. The Bornite Project is not currently in production; for contemplated exploration or development activities see above. 85 Table of Contents Mineral Resource Estimate Comparison for Bornite Between November 30, 2024 and 2023 For ease of comparison, the estimates for each project are shown on a 100% basis. Trilogy’s attributable interest is 50% of the tonnage and contained metal stated in the tables. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Category ​ Tonnes (Mt) 2023 ​ Tonnes (Mt) 2024 ​ Percentage Change Contained Metal Cu (Mlb) 2023 Contained Metal Cu (Mlb) 2024 ​ Percentage Change Inferred In-Pit 170.4 170.4 0.0% 4303 4303 0.0% Inferred Outside Pit South Reef 22.0 27.5 25.0% 1690 1687 -0.2% Inferred Outside Pit Ruby Zone 10.4 10.4 0.0% 521 521 0.0% Total Inferred 202.7 208.2 2.7% 6514 6511 0.0% ​ Internal Controls Over Mineral Resource and Reserve Estimates Trilogy has internal controls for reviewing and documenting the information supporting the mineral resource and mineral reserve estimates, describing the methods used, and ensuring the validity of the estimates. Information that is used to compile mineral resources and reserves is prepared and certified by appropriately qualified persons at the project sits and is subject to our internal review process which includes review by appropriate management and a Qualified Person employed by Trilogy. The corporate Qualified Person presents the mineral resource and reserve information to the Board’s Technical Committee for their review on a periodic basis. ​