What changed in this filing

/stocks — the workspaceLOADING

Item 2. Properties

2025-02-14 compared with 2024-02-09 · 280 added, 122 removed, 1353 unchanged (23% of the section changed)

1 unchanged sentence

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 - cobalt 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”).

Mineral Resource Summary Table as of November 30, 2024

3 unchanged sentences

Bornite – 50% Attributable Interest

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, 2023 and reviewed the reserves and resources in the S-K 1300 Arctic Report and the S-K 1300 Bornite Report and confirmed that the reserves and resources remain current as of November 30, 2023.

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.

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.

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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.

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.

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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 with a cut-off grade of 1.79% Cu.

The cut-off grades include the considerations of a $4.05/lb Cu price, process recovery of 87.2%, open pit mining costs of $3.21/t mined, underground mining cost of $73.62/t mined, process cost of $19.14/t processed, G&A cost of $4.14/t processed, treatment, refining, sales cost of $0.73/lb Cu in concentrate, road use cost of $8.04/t processed, 2% NSR royalty.

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.

Mineral Reserve Estimate as of November 30, 2024 for the Arctic Project, Alaska USA

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Probable Mineral Reserves – 50% Attributable Interest

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.

Mineral Reserves were estimated assuming open pit mining methods and include a combination of internal and contact dilution.

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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.

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.

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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 Arctic Project contained in this Form 10-K is derived from the (i) 2023 S-K 1300 report for Arctic titled “Arctic Project 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.

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”).

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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.

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.

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Trace amounts of electrum are also present.

Gangue minerals associated with the mineralized horizons include quartz, barite, white mica, chlorite, stilpnomelane, talc, calcite, dolomite and cymrite.

Gangue minerals

associated with the mineralized horizons include quartz, barite, white mica, chlorite, stilpnomelane, talc, calcite, dolomite and cymrite.

Deposit Types

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Ambler Sequence west of the Arctic deposit

Work Completed

COU, Dead Creek, Sunshine, Red

Geotechnical Structural Mapping

Work Completed

Arctic deposit surface geology

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Soils - VTEM 26-29, JA Creek, West Dead Creek, Dead Creek

Soils - Sub Arctic Valley, South Cliff, VTEM 26-29, VTEM-41, VTEM-23 , East and West Sunshine, Tom

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

Work Completed

Tom, Kogo/White Creek, SK, Cynbad, East Arctic, West Dead Creek, Dead Creek, 98-9/Pipe, Z, Nora, Ambler, Nani

Creek, 98-9/Pipe, Z, Nora, Ambler, Nani

Streams silts - Core area prospects

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2015, 2016, 2018, 2019, 2021, 2022

Arctic P FS and FS slope design

Arctic PFS and FS slope design

2015, 2016, 2017, 2018, 2019

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PEA – Open Pit

Work Completed

Pre-Feasibility Study

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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 conducted included mineralogy and flotation testing, locked cycle tests, comminution tests, copper/lead separation testwork, talc optimization testwork, and thickening and filtration testing.

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:

Historical testwork completed prior to 2012, primarily by Kennecott Research Centre in Utah, and Lakefield Research Ltd., Lakefield, Ontario;

Preliminary Trilogy testwork conducted at SGS Mineral Services, Vancouver (“SGS Vancouver”), in 2012 to 2015;

Preliminary Trilogy testwork conducted at SGS Mineral Services, Burnaby (“SGS Burnaby”), in 2012 to 2015;

Detailed Trilogy testwork conducted at ALS Metallurgy in Kamloops, BC (“ALS Metallurgy”) in 2015 to 2019;

Amber Metals testwork conducted at ALS Metallurgy and SGS Mineral Services in 2021 to 2022.

In 2012, SGS Vancouver 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.

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.

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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 Vancouver and ALS Metallurgy testwork programs to support the design and economics of efficient grinding of the Arctic materials.

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.

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Mineral Resource Estimate

Mineral Resources have not been previously disclosed under S-K 1300 standards prior to fiscal year ended November 30, 2022 and definitions in a filing with the United States Securities and Exchange Commission (SEC).

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 .

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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 2014 CIM Definition Standards in the NI 43-101 Arctic Report and 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.

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.

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All Indicated Mineral Resources have been converted to Mineral Reserves.

Mineral Resources are reported in place (point of reference) and on a 100% basis;

however, Trilogy Metals attributable interest is 50% of the tonnes and metal content.

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

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Inferred – 50% Attributable Interest

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, 2023 and reviewed the resources in the S-K 1300 Arctic Report confirmed that the resources remain current as of November 30, 2023.

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.

Mineral Resources were prepared in accordance with the standards and definitions of S-K 1300.

1 unchanged sentence

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.

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The Mineral Resource estimate is reported exclusive of those Mineral Resources that were converted to Mineral Reserves.

Trilogy Metals’ 50% attributable interest is stated in the table.

Figures may not sum due to rounding.

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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.

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.

The Mineral Resource estimate is reported inclusive of those Mineral Resources that were converted to Mineral Reserves.

Trilogy Metals’ attributable interest is 50% in the table.

Trilogy Metals’ attributable interest is 50% of the amounts in the table.

Figures may not sum due to rounding.

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Mineral Reserve Estimates

Mineral Reserves were not disclosed under S-K 1300 standards prior to fiscal year ended November 30, 2022 in a filing with the SEC.

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 CIM Definition Standards for Mineral Resources and Mineral Reserves (May 10, 2014) in the NI 43-101 Arctic Report and 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.

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.

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The Mineral Reserves statement is shown in Table 9.

Trilogy Metals attributable interest is 50% of the tonnes of the Mineral Reserves.

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

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Probable Mineral Reserves – 50% Attributable Interest

A Qualified Person and an employee of the Company, has reviewed the reserves in the S-K 1300 Arctic Report and confirmed that the reserves remain current as of November 30, 2023.

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.

Mineral Reserves were estimated assuming open pit mining methods and include a combination of internal and contact dilution.

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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.

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.

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and transport cost $270.98/t concentrate.

All selling terms are as of November 2022 and transport cost is as of July 2020.

Fixed royalty percentage of 1% NSR.

Trilogy Metals’ attributable interest is 50% of the tonnage stated in the table.

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:

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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 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.

A significant amount of baseline environmental data collection has occurred in the area including surface and groundwater

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

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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 by guiding, local development projects, employment through tribal and city councils, government aid, and employment both in and outside of their home villages.

Residents largely live a subsistence lifestyle with incomes supplemented

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.

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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%.

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.

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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 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.

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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.

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● Mine development

● Waste Rock placement and Tails Dam

● Waste Rock placement and Tailings Dam

● Arctic Project water management and treatment

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Precious metals attendant with the concentrates will be largely payable.

While 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.

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.

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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 Arctic Project.

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) 2023 S-K 1300 report for Bornite titled “Technical Report Summary on the Initial Assessment of the Bornite Mineral Resource, Northwest, Alaska, USA” dated November 30, 2022 prepared by Wood Canada Limited, which is unaffiliated with Trilogy (“S-K 1300 Bornite Report”) and the (ii) technical report titled “NI 43-101 Technical Report on the Mineral Resource Update of the Bornite Project, Northwest Alaska, USA” with an effective date of January 26, 2023, prepared by Wood Canada Limited (the “NI 43-101 Bornite 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 (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.

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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.

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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 dedicated to advancing the projects.

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.

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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 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;

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).

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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.

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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 reduction procedures limit their usefulness.

Where data are available in these earlier surveys, the lack of details in data acquisition, coordinate systems, and data

reduction procedures limit their usefulness.

The only complete geophysical report that is available concerns down-hole IP/resistivity results.

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1 Ore Body” in a 1986 paper in Economic Geology.

to the historical work, Ty Connor at the Colorado School of Mines recently completed a Master’s thesis which reported on the timing of alteration and mineralization at the Bornite deposit.

Kennecott conducted two technical reviews of the groundwater conditions and a summary of the findings related to the flooding of the exploration shaft.

20 unchanged sentences

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 (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.

The Bornite succession is now understood to be a carbonate slope deposit characterized by

(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.

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.

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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.

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.

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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).

Some appreciable silver values are also found at Bornite, particularly in association with bornite-rich mineralization in the South Reef area and Ruby Zone.

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.

Copper-cobalt-silver-zinc mineralization at Bornite forms disseminations, veins, and massive sulphides in stacked, semi-stratabound bodies closely associated with secondary hydrothermal dolomitization.

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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 by 49 km which totalled 2,852-line km.

The survey covered a rectangular block approximately 18 km

by 49 km which totalled 2,852-line km.

The survey was flown at 300 m line spacing with a line direction of N20E.

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and any alteration associated with mineralization.

Acquisition of this 2D dataset used 500 g seismic charges as a means of producing seismic energy.

Acquisition of this 2D

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.

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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.

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.

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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.

the Bornite sequence and to identify and distinguish different types/ages of dolomitization, including, if possible, their relation to mineralization.

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).

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The hole intersected argillaceous phyllite (probable Beaver Creek) followed by Bornite sequence:

alternating tan phyllitic limestone, tan limey phyllite, argillaceous/carbonaceous phyllitic limestone, limestone clastic breccia, limestone, and argillaceous limestone clastic breccias and dolostone clastic breccia.

alternating tan phyllitic limestone, tan limey phyllite, argillaceous/carbonaceous phyllitic limestone, limestone

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.

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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 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.

The results of these two holes are being compiled and interpreted.

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.

From 1957 to 2019, a total of 273 holes targeted the Bornite deposit during 24 different campaigns;

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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 surface and from 1968 to 1972, BX diameter core was most commonly drilled.

In 1968, drilling activity moved back to the

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).

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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.

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.

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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, 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.

The Wood QP is not aware of any drilling,

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

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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 deposit area by helicopter.

During the visit, he reviewed drill core, measured drill collars with a handheld GPS unit, visited the historical trench area and viewed the

deposit area by helicopter.

Wood’s geology and resource QP also measured five surface drill collars with a handheld GPS unit.

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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 testwork 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 testwork suggested that 97.64% of the copper was recoverable in a concentrate assaying 43.90% Cu.

grinding to 5% passing +200-mesh was required to obtain the liberation of copper minerals from pyrite necessary for such a high recovery.

Mineralogical testwork 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 testwork 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 testwork on mineralized samples collected from the South Reef area.

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 testwork aimed at producing saleable copper concentrates.

The testwork continued into 2013.

In 2017, Trilogy Metals contracted SGS to conduct detailed metallurgical testwork 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 testwork.

This testwork 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 testwork.

Metallurgical testwork 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 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 CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines (November 2019) and reported in accordance with CIM Definition Standards for Mineral Resources and Mineral Reserves (CIM Definitions Standards, 2014) and the standards and definitions of S-K 1300.

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.

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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 testwork to establish the appropriate process options available to produce marketable pyrite-cobalt concentrate.

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.

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The deposit is amenable to either open pit or underground mining methods.

Underground mining assumes a combination of longhole stoping and cut-and-fill methods with an average assumed mining cost $73.62/t mined.

Using these parameters an open pit marginal cut-off grade of 0.5% Cu and an underground break-even cut-off grade of 1.79% Cu were determined.

The underground mining shape is based on a 1.79% Cu grade shell and then a filter was applied to remove isolated blocks that are outside of the underground mining shape that would not meet reasonable prospects for eventual economic extraction.

A 20 m pillar was imposed between mining the pit shell and underground mining shapes.

The Wood QP considers industry consensus on a long-term price forecast on mineral reserves and cash flows of $3.50/lb Cu is reasonable.

It is in accordance with industry-accepted practice to use higher metal prices for the mineral resource

estimates than the pricing used for mineral reserves.

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.

Mineral Resources are classified in accordance with S-K 1300 and the CIM Definition Standards for Mineral Resources and Mineral Reserves (May 2014).

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 a breakeven cut-off grade of 1.79% Cu.

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).

Table 1 – Mineral Resources for the Bornite Deposit as of November 30, 2023

Table 1 – Bornite Mineral Resources Statement as at November 30, 2024

Average Grade

Contained Metal

Underground Development

Total Inferred – 100%

Total Inferred – 50% Attributable Interest

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, 2023 and reviewed the resources in the S-K 1300 Bornite Report and confirmed that the resources remain current as of November 30, 2023.

Mineral resources are prepared in accordance with the definitions in S-K 1300 and CIM Definitions Standards (2014).

No mineral reserves have been estimated on the Bornite Property.

Wood is the third-party firm responsible for preparing the mineral resource estimate.

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.

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.

Mineral resources are reported in place (point of reference).

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 with a cut-off grade of 1.79% Cu.

Trilogy Metals’ attributable interest is 50% of the tonnage and contained metal stated in the table.

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.

Underground development material uses a marginal cut-off of 0.70% Cu where the mining costs are excluded.

Figures may not sum due to rounding.

The mineral resources are reported in place (point of reference).

The mineral resource estimates are shown on a 100% ownership basis, of which Trilogy Metals’ share is 50%.

Table 2 – Portions of South Reef Mineral Resource Amenable to Underground Mining

Cut-off (Cu %)

Average Grade

Contained Metal

In-Pit South Reef 1

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Total South Reef

Subset of the mineral resource and is not additive to the in-pit mineral resource reported in Table 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.

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.

Restatement of the mineral resources outside of the pit as reported in Table 1 and is not additive to Table 1.

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 factors that could affect the mineral resource estimate include:

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

● Changes to the mineral resource estimate methodology

● Adjustments to address the perceived high-grade bias in the higher-grade copper

● 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

● Additional work may allow the inclusion of cobalt in future updates to the mineral resource statement and expand the mineral resource.

● Approval for developing road access to site.

● 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.

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

Average Grade

Mineral resources within the mine plan were estimated using sublevel stoping underground mining method and includes variable dilution and a mining recovery of 95%.

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.

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%.

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.

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.

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.

Table 4 – Summary of Capital Cost Estimate

Initial Capital

Sustaining Capital

Total Capital

Onsite Infrastructure

Offsite Infrastructure

Indirect Costs

Owners’ Costs

Provisions/Contingency

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

Unit Cost of Mineralized Material Processed

Underground Mining

Water Management

Surface Operations Cost

G&A = general and administrative

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.

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

Pre-Tax Valuation Indicators

Undiscounted Cumulative Cash Flow

Payback Period (from start of operations)

IRR Before Tax

Post-Tax Valuation Indicators

Undiscounted Cumulative Cash Flow

Payback Period (from start of operations)

IRR After Tax

NPV = net present value;

IRR = internal rate of return

Exploration, Development, and Production

Based on the mineral resource estimates and existing metallurgical testwork presented in this NI 43-101 Bornite Report and S-K 1300 Bornite Report, the QPs recommend Trilogy Metals continue to improve their understanding of the Bornite property’s structural geology and their confidence in the database with additional re sampling, drilling and database reviews, scoping study as well as conduct additional metallurgical testwork, hydrogeological and geotechnical assessments, and environmental studies totalling between $16.8 and $19.9 million.

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

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Much of the carbonate belt has still yet to be evaluated.

In addition, airborne geophysics completed in 2006 show the Bornite carbonate sequence and the bounding stratigraphy dip to the north under the Ambler Lowlands toward the Ambler Schist Belt.

In addition, airborne geophysics completed

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.

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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.

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.

Tonnes (Mt) 2023

Tonnes (Mt) 2024

Percentage Change

Contained Metal Cu (Mlb)

Percentage Change

Inferred In-Pit

Inferred Outside Pit South Reef

Inferred Outside Pit Ruby Zone

Total Inferred

Internal Controls Over Mineral Resource and Reserve Estimates

2 unchanged sentences

The corporate Qualified Person presents the mineral resource and reserve information to the Board’s Technical Committee for their review on a periodic basis.

Mineral Reserve and Resource Estimate Comparison Between November 30, 2023 and 2022

Mineral Reserves Comparison for Arctic

There were no changes to the mineral reserve estimates for the Arctic project from November 30, 2022 to November 30, 2023.

Mineral Resources Comparison for Arctic

There were no changes to the mineral resource estimates for the Arctic project from November 30, 2022 to November 30, 2023.

Mineral Resources Comparison for Bornite

There were no changes to the mineral resource estimates for the Bornite project from November 30, 2022 to November 30, 2023.

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 2. Properties