Item 2. Properties
Item 2. Properties
CAUTIONARY NOTE REGARDING DISCLOSURE OF MINERAL PROPERTIES
Mineral Reserves and Resources
We are subject to the reporting requirements of the Exchange Act and applicable Canadian securities laws, and as a result we report our mineral resources according to two different standards. U.S. reporting requirements, are governed by Item 1300 of Regulation S-K (“S-K 1300”), as issued by the SEC. Canadian reporting requirements for disclosure of mineral properties are governed by National Instrument 43-101 Standards of Disclosure for Mineral Projects, as adopted from the definitions provided by the Canadian Institute of Mining, Metallurgy and Petroleum. Both sets of reporting standards have similar goals in terms of conveying an appropriate level of confidence in the disclosures being reported, but the standards generally embody slightly different approaches and definitions.
In our public filings in the U.S. and Canada and in certain other announcements not filed with the SEC, we disclose measured, indicated and inferred resources, each as defined in S-K 1300. The estimation of measured resources and indicated resources involve greater uncertainty as to their existence and economic feasibility than the estimation of proven and probable reserves, and therefore investors are cautioned not to assume that all or any part of measured or indicated resources will ever be converted into S-K 1300-compliant reserves. The estimation of inferred resources involves far greater uncertainty as to their existence and economic viability than the estimation of other categories of resources, and therefore it cannot be assumed that all or any part of inferred resources will ever be upgraded to a higher category. Therefore, investors are cautioned not to assume that all or any part of inferred resources exist, or that they can be mined legally or economically.
Technical Report Summaries and Qualified Persons
The scientific and technical information concerning our mineral projects in this Annual Report on Form 10-K have been reviewed and approved by “qualified persons” under S-K 1300, including our Chief Operating Officer, Walter Hunt. For a description of the key assumptions, parameters and methods used to estimate mineral reserves and mineral resources included in this Annual Report on Form 10-K, as well as data verification procedures and a general discussion of the extent to which the estimates may be affected by any known environmental, permitting, legal, title, taxation, sociopolitical, marketing or other relevant factors, please review the Technical Report Summaries for each of the Company’s material properties which are incorporated by reference into, this Annual Report on Form 10-K.
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Golden Crest Project (United States)
1. Property Description and Location
(map of Golden Crest project)
The Golden Crest project is in the northern Black Hills of western South Dakota in Lawrence County. A map of the project location is shown above. The Golden Crest project is comprised of 1,707 unpatented lode claims, with an associated area of approximately 33,000 acres. Two hundred forty-one of the claims are leased from Golden Crest II, LLC , a Wyoming limited liability company (“GC LLC”) and 27 unpatented claims (“Easter Claims”) are leased from the Easter Project, LLC, a Wyoming limited liability company. All the remaining claims are owned by Solitario and were staked throughout 2021 and 2022.
Solitario acquired its interest in the GC Claims in May 2021 by entering into the Golden Crest Agreement with GC LLC. Terms of the Golden Crest Agreement include scheduled payments to the underlying owner of $65,000 paid upon signing and an obligation to pay the underlying owner $60,000 at the first anniversary date. To continue the lease, Solitario has agreed to pay, at its option, the underlying owner escalating annual payments over a five-year period that total $340,000 and annual payments of $150,000 thereafter. Solitario has agreed to pay the underlying owner an additional success fee of $1.00 per ounce of gold in the event Solitario files a 43-101 qualified resource of up to 1.5 million ounces of gold or a maximum of $1,500,000. Solitario has agreed to perform escalating work commitments, at Solitario’s option, on the GC Claims totaling $3,000,000 in work expenditures during the first five years of the lease. Solitario has fulfilled its $600,000 work commitment for the first two years. The term of the Golden Crest Agreement is for twenty years and is automatically extended as long as Solitario is performing any exploration, development or mining activities on the GC Claims. The underlying owner will retain a 2.0% Net Smelter Return royalty. Solitario has the option, but not the obligation, to reduce the Net Smelter Return royalty to 1.0% by paying the underlying owner $1,000,000. GC LLC reserves a three-mile area of interest to its original claim position.
In February of 2022, Solitario entered into a lease agreement (the “Easter Agreement”) whereby Solitario acquired exclusive exploration rights to the Easter Claims in the Black Hills region of South Dakota. The Easter Claims are part of Solitario’s Golden Crest project. Terms of the Easter Agreement include $10,000 paid upon signing, scheduled annual payments to the underlying owner totaling $180,000 through the tenth anniversary, and $30,000 per year thereafter. Solitario has agreed to escalating work commitments, at Solitario’s option, on the Easter Claims totaling $660,000 during the first five years of the lease, with the first year totaling $20,000. All other terms of the Easter Agreement are substantially the same as the Golden Crest Agreement, except there is no area of interest.
Federal maintenance fees and county registration due in 2022 will be approximately $333,000 for all Golden Crest claims currently held by Solitario.
2. Accessibility, Climate, Local Resources, Infrastructure and Physiology
Access to the Golden Crest project by road is by traveling south of the city of Spearfish, SD along several paved and/or gravel roads. US Highway 14A, and US Highway 85 are near the eastern and southern boundaries of the Golden Crest project. Maintained gravel roads extending westward and northward from Highways 14A and 85 as well as numerous unmaintained, numbered secondary United States Forest Service (“USFS”) roads provide additional ingress to the Golden Crest Project.
The Golden Crest Project is in forested highlands with subdued relief separated by steep-sided canyons. Elevations in the immediate area range from approximately 1,500 m to 2000 m. Spearfish Creek, a stream with a perennial flow, is situated east of the property while most other creeks on the property are generally dry in the summer months. Vegetation consists of mixed forest composed of deciduous hardwoods and conifers with sporadic meadows and locally dense underbrush. Stands of timber of commercial value cover the property at higher elevations and are managed by the USFS. Logging activities have been widespread on large portions of the property in the past five to twenty years and are ongoing.
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Climate at the Golden Crest project area is temperate, characterized by hot summers, cold winters and pronounced seasonal variation in precipitation and temperatures. Average annual temperature, as measured at the Spearfish weather station, is 55°F with seasonal variation averages highs of 32°F and 80°F in winter and summer respectively. The average amount of annual rainfall is approximately 26 inches along with 44 inches of snowfall (as measured at the Spearfish recording station). Average precipitation is greater at the higher elevations of the property itself. The mineral exploration season is generally from early April to late November.
The closest population center is Spearfish, South Dakota (population 11,500), which represents the largest city in Lawrence County (population: 25,800). Spearfish is located along Interstate Highway 90, linking Rapid City, South Dakota to Gillette, Wyoming. Spearfish supports light industry, ranching and tourism and hosts a small university, Black Hills State University. The nearest towns to the project area are Lead (population 3,000) and the nearby town of Deadwood (population 1,500), which is the county seat of Lawrence County and a major tourism and gaming center for the area. Mining related employment continues to be an important segment of Lawrence County’s economy. The closest regional airport servicing the area is at Rapid City, situated approximately 80 km southeast along Interstate Highway 90. All major commercial and industrial services are available in Rapid City. Other mining services are available in Lead, South Dakota due to the legacy of the Homestake Mining Company (“Homestake”) operations and the currently producing Wharf mine operated by Coeur Mining. Solitario maintains an office in Spearfish, South Dakota.
3. History
The state of South Dakota ranks third among US states for historic gold production, totaling approximately 51 million ounces produced through 2020, most of which came from the world class Homestake Mine in Lead. The first documented gold discovery in the Black Hills was made by prospectors attached to the Custer Expedition of 1874, who discovered placer gold in gravel bars along French Creek near the present site of Custer, South Dakota. The first known lode claims in the Black Hills were located in the spring of 1876 at the head of Gold Run and Deadwood Gulches. Beginning in the 1890’s, hundreds of mines and mining companies sprang to life in the northern Black Hills, clustered within a relatively small area measuring 20 km long by 16 km wide, and centered around the cities of Lead and Deadwood. Collectively this area, known as the Lead Gold District, is one of the richest gold districts in the world. Gold mining has occurred continuously in the district for 145 years, a record unmatched by any other US gold mining district.
Despite the importance of the Lead Gold District among American mining camps, during the last 140 years very little regional exploration has been conducted on the property which comprises the Golden Crest project. Although the Golden Crest project is adjacent to the Lead Gold District, the lack of regional exploration is apparently due to the widespread cover of the gold bearing Precambrian rocks by younger sedimentary formations. The Golden Crest project is within several kilometers of district mines with significant historical production, yet only a handful of prospect pits occur on the property. It is also thought that the subdued topography, soil cover and absence of outcrops of the distinctive Precambrian rocks that host the ore in the main Lead Gold District resulted in the project area being largely overlooked for such a long time. There is no prior documented work on the property with the exception of three exploration core holes drilled by Homestake in 1993-1994, a small cluster of small prospect pits and a very limited stream sediment survey.
GC LLC staked the 241 GC Claims in 2021. Solitario acquired these claims in May of 2021. Prior to Solitario’s acquisition of the GC Claims, GC LLC completed a minimal amount of work comprised mainly of rock sampling throughout the area. GC LLC discovered gold bearing rocks, mainly along recently disturbed logging roads, in the area where Homestake collected and documented gold anomalies in dry stream sediments. The Easter Claims property, previously known as the 11th Hour Mine, had a longer history with minor production in the early 1900’s where by 1906 nearly 4000 feet of underground workings had been developed. However, an attempt to mill the mined ore was a technological failure and no further work was known to have been completed after 1909.
4. Geological Setting
Geologically, the Black Hills consists of Archean and Proterozoic crystalline rocks that are overlain by Paleozoic rocks ranging in age from Cambrian to Pennsylvanian. Precambrian rocks in the Lead window consist primarily of Precambrian metasedimentary rocks and minor extrusive metabasalts and intrusive gabbros. The Paleozoic sequence of marine sedimentary rocks (mainly carbonates and calcareous sediments) contains five formations, dominated by the Cambro-Ordovician Deadwood Formation at its base and the Mississippian-aged Pahasapa Group (regionally known as the Madison Group) at its top. Thin stratigraphic units including the Ordovician Winnipeg and Whitewood Formations and Devonian Englewood Formation are present. The Deadwood Formation is the most important Paleozoic host for Tertiary replacement gold mineralization and paleoplacer gold deposits. The Mississippian Pahasapa Group contains three recognizable members that correlate to the Lodgepole Limestone, Mission Canyon Limestone and Charles Formation of the regional Madison Group. The Pahasapa Group is overlain in stratigraphic unconformity by the Minnelusa Formation, a package of Pennsylvanian-aged shallow marine and continental red beds and evaporite successions up to 180 m thick. The upper Pahasapa was strongly karsted in the Black Hills prior to deposition of the Minnelusa, producing the world’s largest known paleo-cave systems.
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This karsted carbonate package is an important lithologic host for alteration and mineralization across the Golden Crest project. The thickness of the Paleozoic sedimentary package varies from east to west across the Lead District from less than 240 m thick east of Deadwood to over 365 m thick at Tinton in the west. Tertiary igneous rocks preferentially invade several shale horizons in the Deadwood Formation and have locally inflated the thickness of the Cambro-Ordovician section by up to 300 m. Igneous rocks rarely intrude higher stratigraphic units except for a few pre-mineralization laccolithic stocks and plugs.
The Golden Crest project area is centered on a broad synform separating the Lead and Tinton domes in the west-central part of the Lead Gold District. Geographically the synform constitutes a broad plateau 40 km long and up to 20 km across with little structural or topographic relief. The surface of the plateau is dominated by Upper Paleozoic rock units, the Mississippian Pahasapa Group and the Pennsylvanian Minnelusa Formation. No Precambrian is exposed on the Golden Crest project property and only three diamond drill holes have been drilled into these Precambrian rocks.
5. Prior Exploration and Recent Work
The first known mineral exploration work on the property was a limited dry stream sediment survey conducted by Homestake from 1988 to 1993 over a 250 square kilometer area. The results of this survey pointed to a seven square kilometer area of anomalous gold values that was subsequently staked by the GC LLC and leased by Solitario. Homestake drilled three deep exploration core holes in 1993-1994 on Solitario’s current property, but not in the area of the anomalous gold values in dry stream sediments. The objective of these holes was to test for the presence of the Precambrian Homestake Formation that hosts the prolific past-producing 42 million-ounce Homestake gold deposit. Two of the three holes intersected the Homestake Formation.
From approximately 2017 to 2020, GC LLC conducted surface exploration consisting of collecting 251 rock float samples mainly exposed in and near recently constructed logging roads. Of these, 103 samples contained gold values greater than 20 parts per billion (“ppb”) gold, with 12 samples containing greater than 1,000 ppb gold. Many of the collected rock samples were siliceous hydrothermal breccias (jasperoids) that occurred as narrow veinlets cutting the limestone formation at surface.
In March 2021 Solitario started exploration activities in the area. Exploration largely consisted of widespread sampling of suspected mineralized and hydrothermally altered rock float, primarily from the Pahasapa and Minnelusa Formations and systematic soil sampling on a grid. Outcrop or subcrop is rare so rock sampling is often limited to float which is resistant to weathering. The topography of most of the property is flat to very gently rolling so the lateral transport of the surficial rocks is minimal.
Apart from the float rock which is highly resistant to weathering, the inference of the subcropping geology is limited to areas where the topography is less flat and those areas where road cuts or road beds expose “C” horizon soils. The inability to observe outcrop limits the ability to detect and interpret the geometry and thickness of zones of alteration, so a soil sampling program was initiated property-wide to assist in the identification of new target areas for mapping and more detailed rock sampling. Exploration work during the past two years has consisted of grid soil sampling, select grab rock sampling of float and less commonly bedrock, hand-dug trenching, geologic mapping and Induced Polarization ground geophysics.
6. Mineralization
The Black Hills are unique for the remarkable spatial superposition of several genetic styles of gold mineralization formed over >2 billion years of geologic history. In excess of 90 million ounces of gold (recorded past production + unmined resources reported from published sources believed to be accurate, but not verified) are contained within five distinct styles of gold deposits in roughly a 300 square kilometer area. This is thought to represent the greatest endowment per square kilometer of any gold district in the United States. The repeated formation of large gold deposits over time in the same small geographic area argues for a fundamentally gold-enriched area of the earth’s crust that has persisted since the Archean time. Solitario’s property does not contain any historic producing mines nor resources and the presence of nearby gold deposits does not indicate that economic gold deposits are present on the Golden Crest project.
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A Laramide-aged igneous belt of alkalic magmatic intrusive centers occurs along a linear WNW-trending belt for approximately 150 km across the northern Black Hills and includes dozens of intrusive stocks and laccoliths and innumerable dikes and sills concentrated in five magmatic centers. These Tertiary-aged intrusive rocks have remobilized important orogenic gold mineralization in the Precambrian basement into overlying Paleozoic rocks. In the Ruby Basin camp at the Wharf Mine Complex, thick pre-mineral igneous sills acted as permeability barriers within the Deadwood Formation that resulted in the deposition of gold mineralization.
Alteration, gold and trace element enrichment in the Pahasapa formation at the Golden Crest project is viewed as a possible indication of replacement-style epithermal mineralization in stratigraphic units lower in the sedimentary sequence (e.g. Upper and Lower Deadwood Formation). Ore-forming magmatic hydrothermal fluids ascended from mineralizing centers may have passed through overlying Paleozoic carbonate sections along subvertical faults and fractures, becoming progressively cooler and diluted by ground water, and depositing trace elements and gold. This extensive hydrothermal fluid interaction is interpreted to have resulted in widespread low-temperature alteration of limestones, silicification and geochemical anomalism +/- gold mineralization in the Pahasapa Formation.
Over twenty gold-enriched target areas have been identified by Solitario by select rock grab sampling. All of these prospects have returned anomalous gold assays, with fourteen containing multi-gram gold per tonne and the remaining prospects returned values between 0.1 and one-gram gold. with fourteen containing multi-gram gold per tonne and the remaining prospects returned values between 0.1 and one-gram gold.
Late in the 2021 field season, Solitario received very high-grade gold values from select surface grab rock samples at the Downpour target area. Additional surface sampling was conducted in the immediate area of the high-grade samples and eight continuous three-meter (total 24 meters) rock-chip channel samples were also collected. In 2022, Solitario sampled an additional 127.5 meters of trenching at Downpour, where significant high-grade intervals were found as shown in the lefthand Downpour Target map below.
Solitario also expanded its exploration search area at the Downpour Prospect in 2022 and successfully enlarged the potential target area for high-grade gold mineralization. As shown on the Rock Grab Sample Assay Map on the righthand side below, mineralization at Downpour has now been identified over an 800-meter-long strike length, with a width of up to 500 meters wide. This prospect remains open in three directions.
Downpour trenching results with assay values in gpt gold.
Greater Downpour area with rock grab sample assay results.
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In 2022, Solitario discovered a new area of significant mineralization within a generalized area called Ponderosa. Select grab sampling of float, weathered bedrock and bedrock yielded both low- and high-grade gold mineralization. Three centers of mineralization were initially identified by select grab samples: Geyser, Spur and Zig Zag. Based on these very favorable results, a trenching program was initiated in all three areas. Assay results for both the select rock grab samples and trenching samples are presented on the map below:
Geyser-Spur-Zig Zag prospect area with gold (gpt) assays for rock grab samples and trench samples.
All areas of trenching on the Golden Crest properties are manually completed using hand tools and are reclaimed as soon as sampling is complete. Revegetation is accomplished utilizing a seed mixture approved by the USFS.
7. Drilling :
No drilling has been conducted at the Golden Crest project by Solitario but is scheduled to begin before the end of the second quarter of 2023, pending permit approvals (see Exploration and Development section below).
8. Sampling, Analysis and Security of Samples
The collection of all select surface grab rock samples was supervised by project geologists, including chain of custody. Rock grab samples were reconnaissance select composite samples that usually displayed alteration, typically silicification, and hydrothermal brecciation. Many of the select grab samples were rock float. These samples were derived from the underlying bedrock in the immediate area, with little transport due to the subdued relief. In all cases the samples are composites within a small area of less than one-square meter or composites of sub-crop or outcrop. The significance of these samples is limited to determining whether gold, or trace elements usually associated with gold, are present within rocks affected by hydrothermal alteration fluids and assay results may not be representative of, nor verify economically mineable mineralization at depth.
Chip-channel and trenching and composite samples were more systematically collected as a measured continuous sample of bedrock, Bedrock + weathered bedrock and weathered bedrock. The chip channel assays are thought to be the most representative of bedrock mineralization in comparison to trench samples that contained weathered bedrock and/or soil. In all cases, chip channel and trenching samples are considered more representative than select grab samples. Samples were analyzed by ALS Laboratories in Reno, NV, a laboratory accredited in accordance with the standards of ISO 17025:2017. The samples were crushed and pulverized, and sample pulps were analyzed using industry standard fire assay methods. A certified reference sample or duplicate was inserted at least every 20th sample.
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9. Prefeasibility Studies : No prefeasibility studies have been conducted on the Golden Crest project.
10. Reserves and Resources : There are no reported mineral reserves or mineral resources on the Golden Crest Project.
11. Drill Hole Permitting, General Reclamation and ESG
Solitario submitted a Plan of Operations (“POO”) to the USFS in late-2021 for 25 widely spaced drill hole locations throughout our property position. After USFS comments, and Solitario responses to those comments, the POO was deemed complete in May of 2022. Respec Company LLC (“Respec”) was engaged by the USFS to complete an Environmental Assessment (“EA”) on Solitario’s proposed POO activities. A draft EA is nearing completion. After a comment period the USFS, in coordination with Respec, will analyze and prepare responses to the public comments, make any required changes to the analysis, prepare a final EA and determine if a Finding of No Significant Impact (FONSI) is appropriate. A USFS decision and an administrative record is anticipated to be filed by the end of the second quarter 2023.
Solitario is committed to a “best practices” policy for all of its exploration activities, whether on private or public lands. For example, all proposed drill hole locations will be located adjacent to or on logging roads or other logging related surface disturbances. In this way drill hole sites will minimize or eliminate new surface disturbance on public land. All rock and soil sampling, as well as hand-tool trenching, conducted to date has been reclaimed as soon as practical after taking of surface samples. We have monitored the impacts of these activities, and in all instances, virtually no visual impacts exist after completion of reclamation. Drilling proposed under the POO and analyzed in the EA will be conducted in accordance with the provisions of the decision document issued by the USFS and any state permits granted for proposed actions.
12. Planned Exploration and Development
For 2023, Solitario is planning to conduct a 4,000-5,000-meter drilling program consisting of approximately eight to twelve exploration core holes. The initiation of this program is dependent upon receiving permit approvals, which are expected before the end of the second quarter of 2023 (see Section 11 above for drill hole permitting process and status). Solitario will also continue its surface exploration program at the Golden Crest project consisting of prospecting for new areas of mineralization through the collection of select rock grab samples, systematic soil sampling, trenching and geophysics.
Florida Canyon Zinc Project (Peru)
Gustavson & Associates completed the S-K 1300 Florida Canyon TRS which is entitled S-K 1300 Technical Report Summary Florida Canyon Zinc Project, Amazonas Department, Peru; Effective Date: February 1, 2022, Report Date: March 15, 2022.
The following summary descriptions of the Florida Canyon project does not purport to be a complete description and is qualified in its entirety by reference to the full text of the S-K 1300 Florida Canyon TRS, which is incorporated by reference as Exhibit 96.1 to this Annual Report on Form 10-K. There has not been material change in the mineral reserves or mineral resources for the Florida Canyon Zinc project since the date of the last technical report summary for the property.
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1. Property Description and Location
(Map of Florida Canyon Property, formerly Bongará)
On August 15, 2006, Solitario signed a Letter Agreement with Votorantim Metais Cajamarquilla, S.A., a wholly-owned subsidiary of Votorantim (now known as Nexa) (both companies are referred to in this Item 2 as ”Nexa”) on Solitario's 100%-owned Florida Canyon zinc project (formerly called the Bongará project), On March 24, 2007, Solitario signed the Framework Agreement with Votorantim for the Exploration and Potential Development of Mining Properties (the “Framework Agreement”), pursuant to, and replacing, the 2006 Letter Agreement. In 2015 Votorantim transferred its interest in the Florida Canyon project to Milpo, an 80%-owned affiliate of Votorantim. In October of 2017, Milpo and Votorantim merged to form Nexa. Nexa is listed on the NYSE under the trading symbol “NEXA.” For the remainder of this Florida Canyon property section, all references to Votorantim, Milpo or Nexa are collectively referred to as Nexa.
The Florida Canyon project consists of 16 concessions comprising 12,600 hectares of mineral rights originally granted to Minera Bongará S.A., our subsidiary incorporated in Peru. The property is located in the Department of Amazonas, northern Peru. Solitario's and Nexa’s property interests are held through the ownership of shares in Minera Bongará S.A., a joint operating company that holds a 100% interest in the mineral rights and other project assets. Solitario currently owns a 39% interest in the Florida Canyon project.
During 2015 Nexa completed the steps required to earn a 61% interest in the Florida Canyon project, with Solitario retaining a 39% interest. Nexa may earn an additional 9% interest (up to a 70% shareholding interest) in Minera Bongará S.A., by sole-funding future annual exploration and development expenditures until a production decision is made. The option to earn the 70% interest can be exercised by Nexa at any time by committing to place the project into production based upon a completed feasibility study. Nexa is the project manager. Once Nexa has committed to place the project into production based upon a feasibility study, it has further agreed to finance Solitario's 30% participating interest until production with a loan facility from Nexa to Solitario. Solitario will repay this loan facility through 50% of Solitario's cash flow distributions from the joint operating company. Solitario completed the funding of $1,580,000 of a drilling program during 2019. Solitario was not obligated to fund under the terms of the Framework Agreement. The paid funding of the drilling program will be treated as an advance on Solitario’s commitment to fund 30% of any future construction development costs of Florida Canyon under the original joint venture agreement. Accordingly, in the event the Florida Canyon project is developed, which cannot be assured at this time, the funds paid to Nexa under this arrangement will reduce the amount of Solitario’s obligation to fund 30% of future development costs, and/or repay loans from Nexa for future development costs at the Florida Canyon project.
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According to Peruvian law, concessions may be held indefinitely, subject only to payment of annual fees to the government. In June 2023, payments of approximately $360,000 to the Peruvian government will be due in order to maintain all the Florida Canyon mineral rights of Minera Bongará S.A. Nexa is responsible for paying these costs as part of its earn-in expenditure. Peru imposes a sliding scale royalty varying from 1% to 12% of the operating profit of a mining operation. The percentage royalty is determined by rule based on the operating margin; however, the minimum royalty is 1% of the revenues.
From time-to-time Nexa may enter into surface rights agreements with individual landowners to provide access for exploration work at the Florida Canyon project. Generally, these are short-term agreements. Nexa has an agreement with the local community which specifies certain obligations and payments that Nexa is required to provide in exchange for community permissions to perform work.
Environmental permits are required for exploration and development projects in Peru that involve drilling, road building or underground mining. The requisite environmental and archeological studies were completed for all past work. Nexa received a permit in 2021 to allow for drilling immediately south and east of the current Florida Canyon drilling area and is currently working on an additional permit for an expanded drilling program. Although we believe that new permits will be obtained in a timely fashion, the timing of government approval of permits remains beyond our control.
2. Accessibility, Climate, Local Resources, Infrastructure and Physiology
The Florida Canyon property is accessed from the coastal city of Chiclayo by the paved Carretera Marginal road, which is a heavily travelled paved national highway that passes approximately eight kilometers south of the deposit. The nearest town to the project is Pedro Ruiz located 15 kilometers southeast of the property. The area of the majority of past drilling and the most prospective mineralization, Florida Canyon, was previously inaccessible by road, the work to date having been done by either foot or helicopter access. Nexa has now completed approximately 40 kilometers of access road and is planning to complete the road access to local communities and the mineralized area of the project in 2023. Nexa maintains project field offices in Pedro Ruiz and a drill core processing facility and operations office in the nearby community of Shipasbamba.
The project area elevation ranges between 1,800 and 3,200 meters above sea level. The climate is tropical with an average annual temperature of approximately 25 o C. Mean annual rainfall exceeds one meter with up to two meters in the cloud forest at higher elevations. Most precipitation occurs during the rainy season, between November and April. Field work is considerably more difficult in the rainy season. Topography is steep, consisting of prominent escarpments and deep valleys. Dense jungle or forest vegetation covers the project area. With the exception of the partially completed access road and approximately 700 meters of tunneling, no permanent infrastructure facilities have been constructed within the project area
3. History
We discovered the Florida Canyon mineralized zone of the Florida Canyon project in 1996. Subsequently, we joint ventured the property in December 1996 to Cominco (now Teck). Cominco drilled 80 core holes from 1997-2000. Cominco withdrew from the joint venture in February 2001, and at that time Solitario retained its 100% interest in the project. We maintained the claims from 2001 to 2006, until the 2006 letter agreement was signed. Nexa conducted surface drilling on an annual basis from 2006 to 2013 and from 2018 to 2019, and underground tunneling and drilling from 2010 to 2013. All significant work on the property has been conducted by our joint venture partners, Cominco and Nexa, and is described below in Section 5, “Prior Exploration and Recent Work.”
4. Geological Setting
The project is located within an extensive belt of Mesozoic carbonate rocks belonging to the Upper Triassic to Lower Jurassic Pucará Group and equivalents. This belt extends through the central and eastern extent of the Peruvian Andes for nearly 1,000 km and is the host for many polymetallic and base metal vein and replacement deposits in the Peruvian Mineral Belt. Among these is the San Vicente Mississippi Valley Type (“MVT”) zinc-lead-silver deposit that has many similarities to the Florida Canyon deposit and other MVT occurrences in the project area.
The geology of the Florida Canyon area is relatively simple consisting of a sequence of Jurassic and Triassic clastic and carbonate rocks which are gently deformed into a broad northwesterly trending domal anticline. The MVT zinc-lead-silver mineralization occurs in the carbonate facies of the Chambara (rock) Formation. This domal anticline is cut on the west by the Sam Fault and to the east by the Tesoro-Florida Fault.
5. Prior Exploration and Recent Work
We conducted a regional stream sediment survey and reconnaissance geological surveys leading to the discovery of the Florida Canyon area in 1996. The discovered outcropping mineralization is located in two deeply incised canyons within the limestone stratigraphy.
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Subsequent to our initial work, Cominco conducted extensive mapping, soil and rock sampling, stream sediment surveys and drilling. This work was designed to determine the extent and grade of the zinc-lead mineralization, to determine the controls of mineral deposition and to identify areas of potential new mineralization. Nexa began work in the fall of 2006 and drilled annually from 2006 through 2013, and in 2018-2019. Underground exploration operations were conducted from 2011-2013. Nexa has more recently continued surface exploration work consisting of geologic mapping and sampling that has identified new surface zinc mineralization to the south and east of Florida Canyon and also 15 kilometers to the north and northwest in areas called San Jose and Naranjitos (see Chambara Project below). Nexa’s expenditures for 2022 were approximately $3.2 million. The two major work activities for 2022 were: 1) advancement and upgrading of the access road to the project area and adjacent communities as part of their community outreach program; and 2) a significant metallurgical testing program (see section 9 below: “Prefeasibility Studies”).
6. Mineralization
Two important styles of mineralization occur at Florida Canyon: Manto-style with mineralization usually localized in favorable carbonate strata in a near horizontal orientation; and a second style with mineralization in a near-vertical orientation occurring within high-angle structural zones. Manto mineralization occurs as both massive to semi-massive replacements and disseminations of sphalerite and galena localized by specific sedimentary facies (rock strata) within the limestone stratigraphy. Often manto-style mineralization is laterally associated with near-vertical structural feeders and karst breccias that cut the carbonate stratigraphy. A total of 11 preferred beds for replacement mineralization have been located within the middle unit of the Chambara Formation. Mineralization is associated with the conversion of limestone to dolomite, which creates porosity and permeability within the rock formations. It is believed that mineralizing fluids passed through structurally controlled vertical feeder zones and into adjacent near-horizontal rock formations to produce mineralized vertical replacement bodies and stratigraphically controlled near-horizontal manto deposits. Drilling of stratigraphic targets has shown that certain coarser-grained facies of the stratigraphy are the best hosts for manto mineralization. Stratigraphically controlled mineralization is typically one to several meters in thickness, but often attains thicknesses of five to ten meters.
Zinc mineralization was originally deposited in the form of sulfide minerals. However, some near-surface mineralization has been oxidized to varying degrees. Approximately 80% of mineralization defined at Florida Canyon is sulfide-dominant with the remainder being mixed sulfide-oxide, or oxide-dominant. Processing sulfide mineralization is commercially more profitable.
Karst features are localized along the feeder faults and locally produce "breakout zones" where mineralization may extend vertically across thick stratigraphic intervals where collapse breccias have been replaced by ore minerals. Mineralized karst structures are up to 50 meters in width (horizontal), up to 900 meters vertically, and up to 1,000 meters along strike.
Evidence for these breakout zones is provided by the following drill holes from various locations on the property:
Breakout
Zone Name
Drill Hole
Number
Intercepts
(meters)
Zinc
%
Lead
%
Zinc+Lead
%
Sam
GC-17
FC-23
58.8
81.5
12.0
4.8
2.8
0.8
14.8
5.6
Karen
A-1
36.2
12.8
2.7
15.5
V-1021
V-21
92.0
5.5
1.7
7.2
South Zone
V-44
V-169
28.3
51.6
15.2
7.1
0.8
0.7
16.0
7.8
San Jorge
V-297
56.6
22.69
1.15
23.84
Dolomitization reaches stratigraphic thicknesses in excess of 100 meters locally. This alteration is thought to be related to the mineralizing event and is an important exploration tool. Continuity of the mineralization is demonstrable in areas of highest drilling density by correlation of mineralization within characteristic sedimentary facies, typical of specific stratigraphic intervals or within through-going observable structural zones in drill core. At Florida Canyon the two largest-sized high-angle zones identified to date are the San Jorge and 1021 zones. These zones represent well-defined north-northeast structural feeder zones. Less important mineralization occurs along northwest and northeast fracture systems. These structures occur in conjugate fractures, with N10º-50ºE trends present at a number of mineralized surface outcrops while trends of N50º-80ºW are identified at other showings.
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7. Drilling
From 1997 through 2001, Cominco drilled 80 surface core holes totaling 24,696 meters. From 2006-2013, Nexa completed 309 surface core holes totaling 77,193 meters. From 2011-2013, Nexa completed 95 underground core holes totaling 15,144 meters. The underground drilling was conducted from 10 drill stations at generally 40-meter centers (two drill stations at 20-meter centers) and entirely within the San Jorge mineralized zone. Anywhere from three to 14 holes were drilled from each of the ten drill stations. The underground drilling was tightly spaced and designed to allow for feasibility-level reserve estimation.
From November 2018 to October 2019, Nexa completed a 39-hole, 17,033-meter core drilling program. The majority of holes were drilled in 2019. The program had three major objectives: 1) extend the San Jorge near-vertical replacement body to the south and the adjacent near-horizontal manto bodies to the east; 2) offset previously drilled hole V-21 in the northern part of Florida Canyon to determine if it represented a significant near-vertical replacement body with horizontal mantos similar to the San Jorge Zone; and 3) extend horizontal mantos in the central and northern parts of the Florida Canyon drilling footprint. All three objectives were successfully achieved.
All past drilling conducted is within a footprint measuring approximately 2.5 kilometers long in a north-south direction and a little over a kilometer in an east-west direction. The entire drill pattern is within what we have informally labeled the Florida Canyon district. Within this district, several zones of strong zinc mineralization have been defined. The three zones with the largest amount of drilling are the San Jorge, the Karen-Milagros and the 1021 zones. Drilling indicates that, for the most part, the entire Florida Canyon district remains open to expansion and the identified zones are interconnected. Better 2018-2019 drill-hole intercepts are provided in the table below:
2018-2019 Mineralized Intersections
Drill Hole
Intercept
Zinc
Lead
Silver
ZnEq*
Number
Meters
(%)
(%)
(grams/t)
(%)
PEBGD-03
1.3
42.7
15.0
83.0
56.9
PEBGD-04
1.3
40.5
0.0
4.8
40.6
PEBGD-08
4.4
16.8
1.1
32.1
18.3
PEBGD-10
48.9
5.2
1.0
11.5
6.2
including
17.5
11.3
2.2
25.4
13.7
PEBGD-15
12.4
14.9
0.0
8.9
15.1
PEBGD-24
4.1
18.6
0.9
5.7
19.5
PEBGD-25
6.3
7.7
0.5
3.2
8.2
And
8.8
5.2
1.5
18.1
6.9
PEBGD-30
6.7
18.4
0.0
10.6
18.7
PEBGD-31
7.4
11.3
1.7
14.5
13.1
PEBGD-32
9.3
23.5
2.8
18.1
26.5
PEBGD-33
9.9
5.9
1.6
12.9
7.7
PEBGD-36
6.1
20.1
5.6
42.4
25.6
And
1.8
35.2
0.5
69.7
37.1
PEBGD-38
9.7
22.8
0.2
11.8
23.2
PEBGD-39
3.3
37.7
9.6
65.5
47.1
*Zn-Eq was calculated using the following price assumptions: Zn=$1.10/lb., Pb=$0.91lb., Ag=$16.50/oz.
Reported intervals are estimated to be at least 80% of the true thickness
Numbers in this table may not add exactly as numbers have been rounded to the nearest decimal
8. Sampling, Analysis and Security of Samples
Core recoveries were typically high within mineralized zones, but occasionally karst caves were encountered, and no core was recovered for intervals generally less than two meters. Core samples were transported from the drill by helicopter in sealed boxes to the processing facility in Shipasbamba. The entire core obtained from each drill hole, usually NQ and HQ size, was logged on site at a core storage facility. All of the core containing sulfide mineralization was cut using diamond saws and half of the core was sent for assay. Intervals of the half-core taken for assay were selected according to geologic criteria under the supervision of the geologist in charge and shipped in sealed bags by land. Cominco used SGS Laboratories (“SGS”) and Nexa used ALS-Chemex, both in Lima, Peru, where all samples were analyzed by ICP (inductively coupled plasma). Any samples that contained greater than 1% zinc were then analyzed by wet chemistry assay for zinc and lead to provide a more accurate analysis of grade.
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Since 2006, Nexa has been in control of all field activities on the project and is responsible for the security of samples. Nexa has indicated that there have been no breaches in the security of the samples. We have reviewed, and periodically been assisted by SRK Consulting (USA) Inc. (“SRK) and Gustavson Associates, both independent international mining engineering firms, to review Nexa’s sampling procedures and believe that adequate procedures are in place to ensure the future security and integrity of samples. No breaches of security of samples are known to have occurred prior to Nexa’s work on the project.
9. Prefeasibility Studies
Nexa, either through its engineering staff or contracted independent mining engineering firms, has conducted prefeasibility-level studies to provide estimates of deposit size and grade, mining and processing recoveries, sizing of appropriate scale of operations, infrastructure design, and capital and operating cost estimates at a level of detail varying from preliminary economic assessment to prefeasibility levels.
Other prefeasibility work completed by Nexa included drilling 16 diamond core holes in 2013 to evaluate geotechnical and hydrological parameters of the mineralized areas for both engineering and environmental purposes. In 2016, Nexa completed a geochemical/metallurgical study that more accurately defined the distribution of sulfide/oxide mineralization based on re-assaying of nearly all past drill-hole samples. This information was critical in resource estimation and accurately estimating metal recoveries. It was assumed that concentrates would be trucked to Nexa’s Cajamarquilla zinc smelter facility in Lima, Peru.
Metallurgical testing to evaluate metal recoveries and various processing options for mineralized material at Florida Canyon was conducted in 2010, 2011 and 2014. These tests on composited samples indicate zinc recoveries above 90% and lead recoveries above 80% were generally achieved for sulfide dominant ores. Increasingly lower recoveries of zinc and lead resulted in direct proportion to the percentage of oxides present in the ore tested. In 2022, Nexa initiated a much more rigorous metallurgical testing program that mainly focused on sulfide mineralization, which is the dominant ore type (78%). This work indicated higher Zn and Pb recoveries as well as higher concentrate grades than was estimated previously. Zn recovery for sulfide mineralization was estimated at 91.7% with a concentrate grade of 56.6% and lead recovery of 88.5% with a concentrate grade of 52.1%.
Solitario and Nexa jointly funded a PEA prepared by SRK for the entire project in 2017 that incorporated a variety of Nexa-generated studies into the analysis. The PEA evaluation included resource estimation, mining and processing recovery estimates, a preliminary mining and processing plan, infrastructure layout, environmental considerations and an economic analysis based on certain base case parameters. The PEA envisioned an underground mining operation with a 2,500 tonne per day floatation mill for processing, resulting in a 12.5-year mine life. It was assumed that concentrates would be trucked to Nexa’s Cajamarquilla zinc smelter facility in Lima, Peru.
Although sulfide recoveries reported in the 2017 PEA were very good, SRK suggested that optimization of processing and metallurgical parameters may result in improved recoveries and concentrate grade. In consideration of this recommendation, in 2022, Nexa initiated a much more rigorous metallurgical testing program that mainly focused on sulfide mineralization, which is the dominant ore type (78%). This work indicated higher Zn and Pb recoveries as well as higher concentrate grades than was estimated previously. Zn recovery for sulfide mineralization was estimated at 91.7% with a concentrate grade of 56.6% and lead recovery of 88.5% with a concentrate grade of 52.1%. The impact of these recent metallurgical testing results combined with the increase in sulfide resources reported in 2021 is expected to have a positive impact on project economics.
Prior to the 2022 S-K 1300 Florida Canyon TRS filing, Solitario filed on SEDAR in Canada a technical report entitled: Amended NI 43-101 Technical Report on Resources, Florida Canyon Zinc Project , Amazonas Department, Peru; Effective Date: February 1, 2021; Report Date: April 5, 2021; and Amended Date: May 27, 2021.
10. Reserves and Resources
There are no reported mineral reserves at the Florida Canyon project. Estimated Mineral Resources for the Florida Canyon deposit are shown in the table below (for greater detail, see “ S-K 1300 Technical Report Summary Florida Canyon Zinc Project, Amazonas Department, Peru; Effective Date: February 1, 2022, Report Date: March 15, 2021, which is Exhibit 96.1 to this Annual Report on Form 10-K. Gustavson & Associates, an international independent mining engineering firm, completed the S-K 1300 Florida Canyon TRS).
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Florida Canyon Total Mineral Resources (100% basis)
Classification
Sum of Tonnes
Zn %
Ag g/t
Pb %
Fe %
Measured
806,945
11.32
15.42
1.39
2.44
Indicated
1,634,702
10.28
14.87
1.31
2.23
Measured + Indicated
2,441,647
10.62
15.05
1.33
2.3
Inferred
14,858,733
9.63
11.28
1.26
2
Mineral resources are not mineral reserves and have not been demonstrated to have economic viability. There is no certainty that the mineral resource will be converted to mineral reserves. The quantity and grade or quality is an estimate and is rounded to reflect the fact that it is an approximation. Quantities may not sum due to rounding.
·
CIM (2014) standards for mineral resources were followed.
·
The effective date of the Mineral Resource Estimate is February 1 st , 2021.
·
The mineral resources are reported using a cutoff of US $41.40/t NSR for sub-level mining areas, US $42.93/t for cut and fill,
and US $40.61/t for room and pillar areas of the mine.
·
The minimum mining thickness was 3 m for sub-levels in cut and fill, and 4 m for room and pillars method.
·
Mineral resources are reported exclusive of mineral reserves.
·
Mineral resources are not mineral reserves and have not demonstrated economic feasibility.
·
Numbers may not sum correctly due to rounding.
Estimates for mineral resources are based on drill results received up to 30 October 2020, with 545 holes and a total length of 136,758.15 m stope shapes for support of economic potential were developed using the stope optimizer tool of Deswik (DSO).
11. Mining Operations
No commercial mining operations to recover metals have occurred on the project. However, in September 2010 Nexa initiated an underground tunneling program to access mineralization and completed its underground work in 2013. As of December 31, 2022, 700 meters of tunneling were completed.
12. Planned Exploration and Development
Nexa plans to conduct a 4,000-to-5,000-meter core drilling program on the Florida Canyon project during 2023. The program is focused on testing for southern extensions to the very well mineralized San Jorge and Sam structure and associated mantos bodies. Drilling is also being considered in the Karen-Milagros and Sam areas to the north of the current resources.
Lik Zinc Project (Alaska)
Gustavson & Associates completed the S-K 1300 Lik TRS which is entitled S-K 1300 Technical Report Summary Lik Zinc Project, Northwest Arctic Borough, Alaska, USA: Effective Date: December 31, 2021, Report Date: March 11, 2022.
The following summary descriptions of the Lik Zinc project does not purport to be a complete description and is qualified in its entirety by reference to the full text of the S-K 1300 Lik TRS, which is Exhibit 96.2 to this Annual Report on Form 10-K and is incorporated by reference herein. There has not been material change in the mineral reserves or mineral resources for the Lik project since the date of the last technical report summary for the property.
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Table of Contents
1. Property Description and Location
(Map of Lik property) Lik.jpg
The Lik property consists of 47 contiguous Alaska state mining claims. The contiguous claims have been grouped together for the purpose of working and operating under a common plan of development for the benefit of all of the claims. The claims cover an area of approximately 6,075 acres (2,460 ha). The claims are located in the southwestern DeLong Mountains in the Wulik River drainage.
To retain the state claims, the Company is required to make annual rental payments to the State of Alaska. The estimated rental payments for 2022 are $9,000. Property holders are also required to perform assessment work with the amount dependent on the area of the State claims. Excess assessment expenditure credits may be carried forward for a maximum of four years. If required, payments may be made in lieu of work to allow retention of the property for a period of five consecutive years. The geographical coordinates of the Lik deposit are approximately 163 o 12’ W and 68 o 10’ N. The figure above illustrates the location of the Lik property.
2. Acquisition History and Joint Venture Arrangement
Solitario acquired its 50% interest in the Lik property from the acquisition of Zazu Metals Corp (“Zazu”) on July 12, 2017. As a result of the acquisition, Zazu became a wholly owned subsidiary of Solitario. Prior to that, Zazu acquired its 50% interest in the Lik property from GCO Minerals Company, a wholly owned subsidiary of the International Paper Company (“GCO”), on June 28, 2007 by making a cash payment to GCO of $20,000,000 and granting GCO a 2% net proceeds interest. GCO also owns an additional 1% net profits interest in the Lik property from a 1997 agreement.
The Company is participating in the exploration and possible development of the Lik property through a joint venture with Teck. The terms of the joint venture were governed by the Lik Block Agreement, made as of January 27, 1983, between Houston Oil & Minerals Exploration Company (“HOMEX”) and GCO. HOMEX assigned its interest in the Lik Block Agreement to Echo Bay Mines Ltd., which, in turn, assigned such interest to Teck. The Lik Block Agreement terminated on January 27, 2018 and the joint venture is now governed under the Joint Operating Agreement (“JOA”) that was attached to the Lik Block Agreement. Since 2018, Teck and Solitario have agreed to annual exploration funding to advance the Lik project. The JOA requires unanimous approval by the parties for annual expenditures in excess of $1 million. Solitario is the operator of the joint venture. Solitario and Teck each retain a 50% interest in the Lik property.
In July 2018, the Company and Teck signed a Joint Exploration Agreement (“JEA”) whereby both parties agreed to fund a surface exploration program on a 50%/50% basis for 2018. Addendums extending the JEA and providing funding for continued exploration were signed in 2019, 2020, 2021, 2022 and a fifth Addendum to the JEA is expected to be signed in 2023. Teck has acted as manager of the exploration programs for the past four years.
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3. Accessibility, Climate, Local Resources, Infrastructure and Physiology
Access to the Lik property is by air to a gravel surfaced airstrip located on the property. The airstrip is capable of handling multi-engine cargo planes. Charter flights may be arranged from a number of sites in northwestern Alaska. The town of Kotzebue, Alaska, which is located about 90 miles from the deposit, is a seaport with commercial air service from Anchorage, Alaska. Kotzebue is the center for access to the nearby Red Dog mine operated by Teck.
The nearest location for which climatic data is available is the town of Kotzebue. The average annual temperature at Kotzebue is 21.6 o F, with seasonal extremes ranging between 77 o F in summer to -58 o F in winter. There is an average of nine inches of rain and 47 inches of snowfall per year. Snow falls are not extreme but blowing snow may form significant drifts. Strong winds are common in most parts of Alaska. Diamond drilling is possible at the Lik property between June and October.
The exposures of mineralization at the Lik property are located at about 800 feet above sea level. West of the deposit, the land rises steeply to peaks about 2,300 feet above sea level. To the southeast, the land slopes down to the Wulik River where the bottom of the valley is about 700 feet above sea level. There is sufficient space for tailings and waste rock disposal, and sufficient water is expected to be available for any proposed processing. Locally, there is vegetation on the property consisting of tundra grasses and low brush made up of willow, dwarf birch, and alder.
There is a camp located on the Lik property. The camp has been used periodically over the last fifteen years. The supply of electric power and workforce accommodation will have to be developed. There are no local resources adjacent to the Lik property. The Red Dog mine, operated by Teck, is located about 13.6 miles southeast of the deposit. Potentially, concentrates could be moved along the access road from the Red Dog mine to the port on the Chukchi Sea. Construction of a road would be required to connect the Lik deposit to the haul road from Red Dog to the port. The port has a shipping season in excess of 100 days.
4. History
The Red Dog ore deposit was originally discovered in 1970 by a geologist undertaking mapping in the De Long Mountains area on behalf of the United States Geological Survey. GCO, in joint venture with New Jersey Zinc Company and WGM Inc. (“WGM”), carried out stream geochemical sampling and reconnaissance for color anomalies. Claims were staked in July 1976 to cover a stream geochemical anomaly on Lik Creek. HOMEX replaced New Jersey Zinc Company in the joint venture in 1976/1977.
Diamond drilling on the Lik property commenced in 1977 and targeted a gossan with a coincident soil and electromagnetic anomaly. The first hole encountered massive lead-zinc-silver-bearing sulfides. By the end of 1977, the joint venture had completed 25 line-miles of ground geophysics, a soil sampling program, and ten diamond drill holes with an aggregate depth of 5,260 feet. In 1978 and 1979, further geological, geochemical and geophysical surveys were carried out, together with the drilling of another 93 diamond drill holes aggregating 51,200 feet. A mineral resource was estimated. The joint venture continued to work in the district in the period 1980 to 1983. However, only limited diamond drilling activity continued on the Lik property. The Lik Block Agreement was signed in 1984.
In 1984, Noranda optioned the GCO holding of the Lik property. Much of Noranda’s activity was concentrated in the Lik North Area where ten diamond drill holes with an aggregate depth of 13,710 feet were completed on four sections. Noranda also drilled holes in the Lik South deposit to better define the deposit. Noranda released its interest in the Lik property after a re-organization of its holdings in the United States. From 1985 through June of 2007, when Zazu acquired its interest in the Lik property, only a limited amount of work was conducted at Lik.
Zazu completed diamond drilling programs during the 2007, 2008 and 2011 summer field seasons. From 2009 through 2014, Zazu conducted a suite of economic, engineering, environmental and metallurgical studies on the Lik property, culminating with the completion of a PEA in 2014.
5. Geological Setting
The regional geology of the Western Brooks Range area is structurally complex. The sedimentary rocks of the area have been significantly disrupted by thrust sheets. The Lik property and the other zinc-lead deposits of the Brooks Range, including Red Dog, are hosted in the Kuna Formation of the Lisburne Group. In the Western Brooks Range, the Lisburne Group includes both deep and shallow water sedimentary facies and local volcanic rocks. The deep-water facies of the Lisburne Group, the Kuna Formation, are exposed chiefly in the Endicott Mountains.
On a district scale, the Lik property is hosted in the Red Dog plate of the Endicott Mountains thrust sheet. The stratigraphically lowest rocks within the Red Dog plate belong to the Kayak Shale. The top of the Kayak Shale is interbedded with rocks of the Kuna Formation. The Ikalukrok Unit has been divided into a lower laminated black shale sub-unit and an upper medium- to thick-bedded black chert sub-unit. The Ikalukrok Unit hosts all of the known massive sulfide deposits in the area.
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Locally, the Lik property is hosted in the upper part of the Ikalukrok Unit of the Kuna Formation. The host rocks are carbonaceous and siliceous black shale, with subordinate black chert and fine-grained limestone. These rocks strike broadly north-south and dip at about 25 o to 40 o to the west. The massive sulfides are overlain conformably by rocks of the Siksikpuk Formation. The sequence is overridden by allochthonous rocks that form high hills north and west of the deposits.
The mineralized sequence is cut by a number of faults. The most significant disruption is the Main Break Fault, which drops the northern end of the Lik deposit down about 500 feet. It is unclear whether there is a change in strike north of the fault, or whether the change is more apparent due to topography. The Main Break Fault strikes east-west and dips north at about 60 o . There is another group of steeper faults that tend to strike northerly or northwesterly and which are interpreted as being both normal and reverse with throws of up to 330 feet.
Low angle thrust faults also cut the rocks at Lik and regionally. These faults are known to cut and displace massive sulfide mineralization at the Red Dog deposits and others in the district.
6. Prior Exploration and Recent Work
The Lik deposit was discovered by GCO in the mid-1970’s by following up on soil color and stream geochemical anomalies. From the late 1970’s to 2011, various geochemical, geophysical, and geologic activities were intermittently conducted to define drill targets. The Lik property was drill tested from the late-1970’s to 2011 by seven different companies. Details of these historical drilling campaigns are discussed above under the heading “History” and below under the heading “Drilling.”
Teck conducted a soil sampling survey, an Induced Polarization (“IP”) geophysical survey and geologic mapping in 2021. The majority of this work was conducted northeast of the Lik deposit exploring for indications of potential new zinc deposits on trend with the Lik deposit in favorable stratigraphy. A total of 381 soil samples were collected. The IP geophysical survey consisted of six survey lines totaling eight kilometers. The results of the IP survey suggested that the rock formation that hosts the Lik deposit may flatten out to the west and be at drillable depths, opening up a whole new area for potential drill testing.
Teck completed a three-hole, 737-meter (2,415 feet) drilling program in 2022. This was the first drilling program conducted since 2011. Drill hole Lik-231 intersected 3.5 meters (11.5 feet) grading 9% zinc and 3% lead. Holes Lik-230 and 232 did not intersect significant mineralization. In addition to the drilling, Teck also conducted traverse geologic mapping to the northwest of the Lik deposit and a ground gravity geophysics with survey data points at 400-meter (1,300-foot) centers. The geophysical survey was also conducted to the northwest of the Lik deposit and was successful in defining a low-amplitude gravity anomaly that requires further follow-up work.
In December 2022, Teck submitted a drilling permit application to the Alaska Department of Natural Resources for 70 core holes, including water sources for drilling. Drill hole location includes step-out drilling surrounding the currently defined deposit as well as location along strike to the northeast and theoretical targets more distant to the deposit. This robust permitting submission allows for significant flexibility in the choice of drill sites for the next five years.
7. Mineralization
The Lik deposit is a black shale-hosted stratiform zinc-lead-silver sedimentary-exhalative (SEDEX) deposit. Mineralization is syngenetic with respect to sediment deposition. Silicification occurs within and peripheral to the main mass of sulfides. Major sulfides in decreasing order of abundance are pyrite-marcasite, sphalerite and galena. The ore textures are massive, fragmental, chaotic, and veined; they rarely show typical sedimentary layering. The portion of the ore body near the surface is oxidized. The deposit is continuous outside the Lik property onto the adjacent 100%-owned Teck property to the south. The southern continuation of the Lik deposit is referred to as the Su deposit, lying on Teck’s Su property.
Within the Lik property, the deposit is divided into two parts by the Main Break Fault. The main part of the deposit within the existing claims is referred to as the Lik South deposit. As presently tested, the Lik South deposit has a surface footprint of about 3,600 feet long and about 2,000 feet wide. It has been tested down dip to a depth of about 650 feet. The Lik South deposit remains open down dip. North of the Main Break Fault, the Lik North deposit has a surface footprint of about 2,300 feet long and about 1,150 feet wide. It has been tested down dip to a depth of about 1,000 feet. The Lik North deposit remains strongly open down dip and to the north.
The deposits strike northerly and dip westerly at about 25 o to 40 o . The mineralization comprises irregular, stratiform lenses. The mineralogy of the sulfides is simple and comprises pyrite, marcasite, sphalerite, and galena. Gangue minerals include quartz (as chert), clay minerals, carbonate and barite. Noranda recognized six different ore types in its logging of drill core. Typical grades of mineralized intersections within the Lik deposit are listed in the table below:
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Table of Contents
Typical Mineralized Intersections
Hole
No.
From
(m)
To
(m)
Length
(m)
Zn
(%)
Pb
(%)
Ag
(g/t)
5
54.56
78.79
24.23
19.72
6.27
126.5
16
80.16
94.49
14.33
21.67
7.01
230.4
21
129.54
135.33
5.79
7.07
1.88
8.6
24
40.87
50.14
9.27
11.09
1.44
51.1
38
45.90
63.76
17.86
8.13
1.80
48.0
38
70.53
87.75
17.22
8.92
2.08
28.8
43
35.66
40.69
5.03
17.66
3.62
8.6
43
60.96
80.28
19.32
9.07
2.49
47.7
43
84.73
91.04
6.31
21.07
5.95
111.4
68
32.31
53.43
21.12
13.34
2.85
56.9
Previous work by GCO determined that sulfides were deposited in four distinct cycles. Individual cycles may be quite thin near the margins of the deposit and the thickest accumulation in a single cycle noted to date is about 45 feet thick. The base of a sulfide cycle begins abruptly with the deposition of sphalerite, galena and pyrite. Typically, the highest grades are found at or within 5-10 feet of the base of a sulfide cycle. In the central portion of the deposit several cycles are stacked and comprise a cumulative thickness of up to 100 feet of mineralization.
8. Drilling
All diamond drill programs are summarized in the following table.
Historical Diamond Drilling Campaigns
Year
Number
of Holes
Aggregate
Depth (m)
Company
1977
10
1,603.3
Managed by WGM
1978
79
10,680.2
Managed by WGM
1979
14
4,931.1
Managed by GCO
1980
3
202.1
Managed by GCO
1983
1
835.2
Managed by GCO
1984
6
1,643.5
Managed by GCO
1985
16
4,883.1
Managed by Noranda
1987
1
696.5
Managed by GCO
1990
3
263.4
Managed by Moneta
1992
2
283.5
Managed by GCO
2007
11
1,393.5
Managed by Zazu
2008
58
6,827.5
Managed by Zazu
2011
25
3,871.0
Managed by Zazu
2022
3
737.0
Managed by Teck
Totals
232
39,065.6
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Zazu completed two diamond drilling programs during 2007 and 2008 to further test the Lik South deposit and to obtain samples for metallurgical testing. At the end of 2008, most of the Lik South deposit had been tested on lines spaced at 200 ft. with holes spaced at about 100 ft.
The 2011 drilling program at Lik combined exploration and development drilling. The exploration drilling focused on improving resource definition, in particular near the transition zone between Lik South and Lik North and also Lik North. The development drilling focused on obtaining additional metallurgical samples and geotechnical drilling for the open pit design and foundation information to assist in infrastructure design. By the end of 2011, a total of approximately 38,328 meters (125,700 feet) of drilling in 229 holes had been completed on the Lik property by the Company (Zazu) and the previous owners.
9. Sampling, Analysis and Security of Samples
Pre-Zazu Drilling
Core recoveries were typically high within the massive sulfides, but lower, more variable recoveries were obtained in the unmineralized and weakly mineralized sections. The entire core obtained from the Lik deposit, usually NQ-size, was logged on site. All of the core containing sulfide mineralization was cut using diamond saws and half of the core was sent for assay. Reference samples were not included in the sample stream. Sample lengths in massive sulfides were typically from two to three feet, but occasionally up to nine feet. Sample lengths were controlled by geology and the location of depth markers in the core boxes.
Most of the samples were assayed by Bondar Clegg Laboratory Group (“Bondar Clegg”) of Vancouver British Columbia. At various times, the laboratory-maintained preparation facilities in Anchorage and Fairbanks Alaska. In the initial years, when the bulk of the drilling was completed, it is believed that sample preparation and analysis were carried out in Vancouver. Bondar Clegg was not a registered laboratory at that time. However, Bondar Clegg was a recognized, reputable laboratory and was experienced in the use of atomic absorption spectrophotometry.
As the entire core was logged and sampled in an isolated field camp, security was not a major concern because access to the camp was closely controlled. It is noted that four different companies (WGM, GCO, Noranda and Moneta Gold Inc.) have completed drilling programs at the Lik property and all of them have obtained consistent results. The work was considered completed to industry standards in use at the time of the work. Sample preparation was completed in the assay laboratory.
Zazu Drilling
Drill core obtained during the 2007, 2008 and 2011 drilling campaigns was logged on site. The entire core containing sulfide mineralization was sawn using diamond saws and half of the core was sent for assay. All massive and high-sulfide cores were sampled. Visual methods were used to select sample boundaries and lengths. The mineralization at Lik is considered to be appropriately logged and sampled. It is not evident that logging or sampling is leading to any bias in the sample results. An examination of logging showed that core recovery in sulfide areas was generally very high.
Core drilled in 2007 was placed in the sample bags, the air was evacuated and replaced with nitrogen. The samples were sent to Kotzebue by charter and then by licensed carrier to Anchorage. The samples were stored under refrigeration in Anchorage. The samples were dispatched to G & T Metallurgical Services Ltd. (“G & T”) of Kamloops, British Columbia, an ISO 9001:2000 certified laboratory for precious metals and base metals. As well as completing metallurgical testing, G & T crushed and analyzed the samples. The 2008 diamond drill core was not required for metallurgical testing and core was handled normally. Sawn samples were securely bagged and boxed on site and dispatched to a facility of ALS Laboratory Group (“ALS Chemex”) located in Fairbanks, Alaska, for sample preparation. Transportation of the samples was through third-party companies that provided secure transportation services. The pulps were analyzed at ALS Chemex located in Fairbanks or Elko, Nevada. Zazu did not participate in any part of the sample preparation or analysis except for cutting core and selecting sample intervals.
Check samples from the 2007 drilling program and all samples from the 2008 drilling campaign were sent to the preparation and assaying facilities of ALS Chemex (ISO 17025 accreditation). Other QA/QC procedures employed by Zazu included the use of blanks (unmineralized core from outside of the mineralized zone) and quartered core duplicates. Zazu was unable to obtain acceptable reference samples for the 2007 field season and reference samples were not included as part of the 2007 ongoing QA/QC program. Reproducibility between G & T and ALS Chemex was found to be good.
.
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10. Prefeasibility Studies
Zazu completed a PEA in 2014 that incorporated a variety of prefeasibility level studies into the analysis. These studies included resource estimation, mining and processing recovery estimates, a preliminary mining and processing plan, infrastructure layout, environmental considerations and an economic analysis based on the base case parameters. The PEA envisioned an open pit mining operation with a 5,500 ton per day floatation mill for processing resulting in a nine-year mine life. Concentrates would be handled through the DeLong Mountain Regional Transportation System road and port system that currently handles all concentrate produced by the nearby Red Dog zinc mine of Teck. A summary of metallurgical testing and mineral processing is provided below. The PEA analyzed the Lik project as a stand-alone operation and assumes construction of its own independent processing, tailings and port facilities. Alternate development scenarios might be developed utilizing infrastructure under the control of the nearby Red Dog operation. However, no agreements are in place to develop such plans and are therefore hypothetical.
Prior to the S-K 1300 Lik TRS report, Solitario filed on SEDAR in Canada: Technical Report; Zazu Metals Corporation, Lik Deposit, Alaska, USA; Report Date: April 23, 2014; Effective Date: March 3, 2014; prepared by JDS Energy and Mining Inc (“JDS”).
11. Metallurgical Testing and Mineral Processing
There have been five metallurgical test work reports issued to date on the Lik ores. The most recent and comprehensive processing and metallurgical testing programs include work performed by G&T and by SGS. Samples collected during drilling in 2007 and 2008 were composited into one Master Composite for testing at G&T in 2008, and later testing by SGS was carried out in 2010 on the remainder of the Master Composite. These key testing results have formed the basis for this economic evaluation of the Lik deposit. Results are summarized in the table below:
Summary of SGS 2010 and G&T 2008 Metallurgical Test Results
Test
Element
Feed
Lead Concentrate
Zinc Concentrate
Grade
Grade
Recovery
Grade
Recovery
SGS 2010
Pb%
2.83
52.00
69.10
1.88
9.70
Zn%
9.56
7.39
2.91
54.60
83.10
Ag gpt
37
55
5.5
68
26.6
G&T 2008
Pb%
2.36
70.30
70.3
1.57
9.4
Zn%
8.47
4.17
1.20
52.20
86.9
Ag gpt
34
68
4.8
64
26.9
Average Used for Mass Balance and NSR Estimates
Pb%
2.60
61.15
69.7
1.73
9.6
Zn%
9.02
5.78
2.06
53.40
85.0
Ag gpt
36
62
5.2
66
26.8
The metallurgical flowsheet for this PEA includes conventional crushing, grinding, and floatation processing methods. Run-of–Mine (ROM) ore will be delivered to a primary crushing plant and stored in a coarse ore stockpile awaiting reclaim into the grinding circuit. Crusher ore will be reclaimed and delivered to a two-stage grinding circuit equipped with a Semi-Autogenous Grinding (SAG) mill and a ball mill in closed circuit with cyclones.
Recoveries from these modeled methods and metallurgical testing conducted to date are anticipated to be 85% of zinc to the zinc concentrate and 69.7% of the lead to the lead concentrate. Silver may also be recovered and payable at times in the zinc concentrate and, more significantly, in the lead concentrate.
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12. Reserves and Resources
There are no reported mineral reserves at the Lik project. Estimated mineral resources for the Lik deposit are shown in the table below (for greater detail, see “ S-K 1300 Technical Report Summary Lik Zinc Project, Northwest Arctic Borough, Alaska, USA: Effective Date: December 31, 2021, Report Date: March 11, 2022, included as Exhibit 96.2 to this Annual Report on Form 10-K. Gustavson & Associates, an international independent mining engineering firm, completed the S-K 1300 Lik TRS).
Lik Mineral Resource Estimate (100% basis)
Location
Indicated Resources
Inferred Resources
Mt
% Zn
% Pb
g/t Ag
Mt
% Zn
% Pb
g/t Ag
Lik South
17.1
8.04
2.69
50
0.71
7.78
1.97
14.3
Lik North
0.51
8.95
2.46
52.9
2.09
8.93
2.98
47.2
Total
17.6
8.07
2.68
50.1
2.8
8.64
2.73
38.9
(1)
Price assumptions for Lik: Zn: $0.92/lb.; Pb: $1.01/lb.: Ag: $19.43/oz
(2)
Mineral resource recoveries for Lik: Zn: 85.0%; Pb: 69.7%; Ag:26.87%
(3)
Mineral resource for Lik is reported at a cutoff grade of 5% Pb%+Zn%
(4)
The preliminary pit optimization was prepared using Datamine Software. The drillhole database, mineralized domain solids and block model were imported into Leapfrog Geo/Edge 2021.2.3 for review.
(5)
For the current resource estimate only surface mining methods were considered. While there may be potential to exploit mineralization via underground mining methods, this was not considered in the current resource statement.
13. Mining Operations
No commercial mining operations to recover metals have occurred on the project.
14. Planned Exploration and Development
Solitario and Teck are in final discussions to potentially fund a 2023 exploration program, with Teck acting as project manager. The program, if approved, consists of drilling two core holes totaling approximately 716 meters (2,350 feet) to test for extensions to the currently defined Lik deposit. An airborne ZTEM survey to measure for resistivity features at depth is also being considered. The drilling and geophysical programs, if approved, would begin in June of 2023.
Chambara Zinc Property (Peru)
In April 2008, we signed the Minera Chambara shareholders’ agreement with Votorantim on Solitario's 100%-owned Chambara zinc project. In 2015 Votorantim transferred its interest in the Chambara project to Milpo. In October of 2017, Milpo and Votorantim merged to form Nexa. For the remainder of this Chambara property section, all references to Votorantim, Milpo or Nexa are collectively referred to as “Nexa.”
The original purpose of the Chambara joint venture was to collectively pool independently owned Solitario
and Nexa properties into a jointly held joint venture. These properties were located within a large area of interest in northern Peru measuring approximately 200 by 85 kilometers, but outside of the Florida Canyon property position. Nexa originally contributed 52 mineral concessions within the area of interest totaling 52,000 hectares to Minera Chambara for a 15% interest in Minera Chambara. We contributed 9,600 hectares of mineral claims and an extensive exploration data base in our possession for an 85% interest in Minera Chambara. Existing and future acquired properties subject to the terms of the shareholders’ agreement will be controlled by Minera Chambara. Minera Chambara dropped selected concessions in 2013 and 2016 and acquired the rights to 13 new concessions totaling 11,600 hectares in 2017. The current claim holdings of Minera Chambara are 48 concessions totaling 36,080 hectares of valid concessions that completely surround the Florida Canyon project area held by Minera Bongará. As of December 31, 2022, Minera Chambara’s only assets are the properties and Minera Chambara has no debt. Nexa may increase its shareholding interest to 49% through cumulative spending of $6,250,000 and may further increase its interest to 70% by funding a feasibility study and providing construction financing for Solitario's interest. Nexa has not met the cumulative spending total as of December 31, 2022. If Nexa provides such construction financing, we would repay that financing, including interest, from 80% of Solitario's portion of the project cash flow.
Significant geochemical anomalies and outcropping mineralization have been identified at several locations on the Chambara property. During 2021 Nexa conducted geologic mapping and geochemical sampling at the San Jose and Naranjitos prospects which were initially discovered by Solitario in the 1990’s. Significant new geologic information collected reveal that at least some of the San Jose mineralization is found in the same stratigraphic location as the Florida Canyon deposit which indicates that the target for future drilling is closer to the surface than previously thought. It is known that the size and strength of the geochemical signature at San Jose is similar to that at Florida Canyon even though surface exploration is still at a very early stage. Even less work has been done at Naranjitos but that project also appears to be very prospective.
There are no reported mineral reserves or mineral resources at the Chambara project.
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Discontinued Projects
We had no mineral property impairments in 2022. During 2021 we recorded $17,000 of mineral property impairment related to our decision to abandon our Gold Coin project in Arizona.
Mineral Resources
The following mineral resources summary represents resources attributable to Solitario’s interest in the mineral resources as provided in the S-K 1300 Florida Canyon TRS at Solitario’s current 39% interest at the Florida Canyon project in Peru and Solitario’s interest in the mineral resources provided in the S-K 1300 Lik TRS at Solitario’s current 50% interest at the Lik project in Alaska, in each case as of the end of the fiscal year ended December 31, 2022.
Lik (1)(3)(5)
Tonnes (000)
Zinc %
Zinc lbs (000)
Silver (g/t)
Oz (000)
Lead %
Lead lbs (000)
Measured Mineral Resources
-
-
-
-
-
-
-
Indicated Mineral Resources
8,800
8.07
1,565,903
50.10
14,175
2.68
520,027
Measured+Indicated Resources
8,800
8.07
1,565,903
50.10
14,175
2.68
520,027
Inferred Mineral Resources.
1,400
8.64
266,717
38.90
1,751
2.73
84,275
Florida Canyon (2)(4)
Measured Mineral Resources
315
11.32
78,553
15.42
156
1.39
9,646
Indicated Mineral Resources
638
10.28
144,512
14.87
305
1.31
18,415
Measured+Indicated Resources
952
10.62
222,988
15.05
461
1.33
27,926
Inferred Mineral Resources.
5,795
9.63
1,230,499
11.28
2,102
1.26
161,000
Total
Measured Mineral Resources
315
11.32
78,553
15.42
156
1.39
9,646
Indicated Mineral Resources
9,438
8.22
1,710,415
47.72
14,480
2.59
538,443
Measured+Indicated Resources
9,752
8.32
1,788,890
46.68
14,636
2.55
547,953
Inferred Mineral Resources.
7,195
9.44
1,497,216
16.65
3,853
1.55
245,275
(1)
Price assumptions for Lik: Zn: $0.92/lb.; Pb: $1.01/lb.: Ag: $19.43/oz
(2)
Price assumptions for Florida Canyon: Zn: $1.20/lb.; Pb: $1.00/lb.: Ag: $16.50/oz
(3)
Mineral resource recoveries for Lik: Zn: 85.0%; Pb: 69.7%; Ag:26.87%
(4)
Mineral resource recoveries for Florida Canyon: Zn: 79.8%; Pb: 74.3%; Ag: 51.7%
(5)
Mineral resource for Lik is reported at a cutoff grade of 5% Pb%+Zn%.
(6)
Mineral resource cut-offs for Florida Canyon are NSR $41.40/t for sub-level stoping, $42.93/t for cut and fill stoping and $40.61/t for room and pillar.
Internal controls
Solitario’s internal controls are designed to provide reasonable assurance that information and processes utilized in assessing its exploration results as well as mineral resource estimation are reasonable and in line with industry best practices. These internal controls include quality assurance and quality control (“QA/QC”) programs in the collection, analysis, verification, storage, reporting and use of drillhole, assay, metallurgical and other technical and scientific information, including the following:
·
Review of joint venture analysis/data/and programs by Solitario qualified personnel, including approval of budgets and annual review of geologic and financial results of programs;
·
All mineral resource calculations are prepared by independent third-party engineering firms and reviewed by Solitario’s qualified person prior to final publication;
·
Maintenance of a complete chain-of-custody, ensuring the traceability and integrity of the samples at all handling stages from collection, transportation, sample preparation and analysis to long-term sample storage;
·
Third-party fully certified labs are used for assays used in public disclosure or resource models; and
·
QA/QC data are regularly verified to ensure that outliers sample mix-ups, contamination, or laboratory biases during the sample preparation and analysis steps are correctly identified, mitigated or remediated.
Mineral resources and mineral reserves are estimates that contain inherent risk and depend upon geologic interpretation and statistical inferences drawn from drilling and sampling analysis, which may prove to be unreliable. See Risk Factors in Item 1A for additional information.
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GLOSSARY OF MINING TERMS
“Allochthonous” means originating in a place other than a place where it was formed.
“Assay” means to test minerals by chemical or other methods for the purpose of determining the amount of valuable metals contained.
“Amphiobile” means any of a class of rock-forming silicate or aluminosilicate minerals typically occurring as fibrous or columnar crystals.
“Anticline” means folds in which each half of the fold dips away from the crest.
“Biotite” means a black, dark brown, or greenish black variety of mica, occurring in many igneous and metamorphic rocks.
“Breccia” means rock consisting of fragments, more or less angular, in a matrix of finer-grained material or of cementing material.
“Carbonaceous” means a compound relating to or containing carbon.
“Chert” means a sedimentary rock of microcrystalline quartz (the mineral form Silicon dioxide - SiO2).
“Claim” or “Concession ” means a mining interest giving its holder the right to prospect, explore for and exploit minerals within a defined area.
“Clastic” means pertaining to rock or rocks composed of fragments or particles of older rocks or previously existing solid matter; fragmental.
“ Deposit ” means an informal term for an accumulation of mineral ores.
“Development” means work carried out for the purpose of opening up a mineral deposit and making the actual ore extraction possible.
“Domal” means of a dome shape.
“Dolomite” means calcium magnesium carbonate, CaMg (CO 3 ) 2 , occurring in crystals and in masses.
“Facies” means the appearance and characteristics of a sedimentary deposit, especially as they reflect the conditions and environment of deposition and serve to distinguish the deposit from contiguous deposits.
“Fault” means a fracture in rock along which there has been displacement of the two sides parallel to the fracture.
“Float” means pieces of rock that have been broken off and moved from their original location by natural forces such as frost or glacial action.
“Galena” means a bluish gray or black mineral of metallic appearance, generally the chief ore of lead sulfide.
“Gabbros” means a granular igneous rock composed essentially of calcic plagioclase, a ferromagnesian mineral, and accessory minerals.
“gpt” means grams per tonne.
“Indicated Mineral Resource” means that part of a mineral resource for which quantity and grade or quality are estimated on the basis of adequate geological evidence and sampling.
“Inferred Mineral Resource” means that part of a mineral resource for which quantity and grade or quality are estimated on the basis of limited geological evidence and sampling.
“Karst” means a landscape that is characterized by the features of solution weathering and erosion in the subsurface. These features include caves, sinkholes, disappearing streams, subsurface drainage and deeply incised narrow canyons.
“Limestone” means a bedded, sedimentary deposit consisting chiefly of calcium carbonate.
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“Manto deposits” means replacement ore bodies that are strata bound, irregular to rod shaped ore occurrences usually horizontal or near horizontal in attitude.
“Metabasalts” means generally fine to medium grained basalts, dominated by plagioclase, quartz, amphibole, and biotite rock.
“Measured Mineral Resource” means that part of a mineral resource for which quantity and grade or quality are estimated on the basis of conclusive geological evidence and sampling.
“Mineral Resource” means as a concentration or occurrence of material of economic interest in or on the earth’s crust in such form, grade or quality, and quantity that there are reasonable prospects for its economic extraction.
“Minnelusa” means a formation as a geologic unit of primarily limestone and dolomite found in the Black hills of South Dakota of the Permian to Pennsylvanian aged limestones and dolomites.
“Mineralization” means the concentration of metals within a body of rock.
“NSR” means net smelter return royalty.
“Ore” means material containing minerals that can be economically extracted.
“Ounce” means a troy ounce.
“Oxide” means a mineral class in which the chemical compound typically contains an 0 -2 oxygen atom in its chemical formula.
“Pahasapa” means a formation as a geologic unit of primarily limestone and dolomite that is exposed in the Black hills of South Dakota of Mississippian aged limestones and dolomites.
”Plagioclaste” means a group of feldspar minerals that form a solid solution series ranging from pure albite, Na(AlSi 3 O 8 ), to pure anorthite, Ca(Al 2 Si 2 O 8 ).
“Pyrite” means a compound of iron sulfide (FeSO2) commonly found in mineral rich areas.
“Reserves” or “Mineral Reserve” means that part of a mineral deposit, which could be economically and legally extracted or produced at the time of the reserve determination.
“Sampling” means selecting a fractional, but representative, part of a mineral deposit for analysis.
“Shale” means a fine-grained sedimentary rock that forms from the compaction of silt and clay commonly referred to as mud.
“Sediment” means solid material settled from suspension in a liquid.
“Sedimentary Exhalative Deposits (SEDEX)” means ore deposits which have been formed by the release of ore-bearing hydrothermal fluids into a water reservoir.
“Silicification” means the process in which organic matter becomes saturated with silica (silicon dioxide).
“Sphalerite” means a very common mineral, zinc sulfide, usually containing some iron and a little cadmium, occurring in yellow, brown, or black crystals or cleavable masses with resinous luster and it is the principal ore of zinc.
“Spectrophotometry” means the quantitative measurement of the reflection properties of a material as a function of its wavelength.
“Stratiform” means formed parallel to the bedding places of surrounding rock.
“Stratigraphy” means the arrangement of rock strata, especially as to the geographic, chronologic order of sequence (age), classification, characteristics and formation.
“Strike” when used as a noun, means the direction, course or bearing of a vein or rock formation measured on a level surface and, when used as a verb, means to take such direction, course or bearing.
“Subcrop” means an occurrence of strata beneath the subsurface of an inclusive stratigraphic unit that succeeds an unconformity on which there is marked overstep.
“Sulfide” means a compound of sulfur and some other element.
“Synform” means A topographic feature which is composed of sedimentary layers in a concave formation.
“Syngenetic” means a mineral deposit that forms at the same time as the surrounding rock.
“Ton” means a short ton (2,000 pounds).
“Tonne” means a metric measure that contains 2,204.6 pounds or 1,000 kilograms.
“Vein” means a fissure, fault or crack in a rock filled by minerals that have traveled upwards from some deep source.