NEWS RELEASE
TNR Gold NSR Royalty Update – Los Azules Copper, Gold and Silver Project – McEwen Copper Reports Improved Copper Recovery
"Vancouver, British Columbia – February 28, 2024: TNR Gold Corp. (TSX-V: TNR) (“TNR”, “TNR Gold” or the “Company”) is pleased to announce that McEwen Mining Inc. (“McEwen Mining”) has provided an update on the Los Azules copper, gold and silver project in San Juan, Argentina. TNR holds a 0.4% net smelter returns royalty (“NSR Royalty”) (of which 0.04% of the 0.4% NSR Royalty is held on behalf of a shareholder) on the Los Azules Copper Project. The Los Azules project is held by McEwen Copper Inc. (“McEwen Copper”), a subsidiary of McEwen Mining.
The news release issued by McEwen Mining on February 22, 2024 stated:
“McEwen Copper Inc., 47.7% owned by McEwen Mining Inc. (NYSE: MUX) (TSX: MUX), is pleased to announce results from the recently completed Phase 1 copper heap leaching metallurgical tests undertaken at SGS Chile Limitada in Santiago, Chile. The test results were produced utilizing conventional bio-heap leaching technology and generated an average copper recovery of 76.0%. This represents an increase of 3.2% over the recovery rate used in the June 2023 Preliminary Economic Assessment (PEA) for Los Azules. These test results were reviewed by Jim Sorensen and Michael McGlynn at Samuel Engineering Inc., who are responsible for the development and oversight of the metallurgical programs.
Metallurgical Testing Delivers a 3.2% Increase in Predicted Copper Recovery at Los Azules
Phase 1 Results
Based on the Phase 1 test results available at the time and prior historical column test work, the PEA used an average copper recovery of 72.8% by employing conventional bio-heap leaching technology (see results published June 20, 2023). Final results of Phase 1 show an increase in the average recovery to 76.0% in approximately 230 days of leaching over the planned 27-year life of the project. Average net acid consumption was also reduced by 8.3% relative to the PEA.
The potential impact of the 3.2% increase in average recovery and 8.3% reduction in net acid consumption can be illustrated by selectively adjusting the PEA Base Case financial model, which results in a life of mine copper cathode production increase of 172,000 tonnes and an after-tax NPV(8%) increase of approximately $262 million. This disclosure should not be taken to modify or update the conclusions of the PEA.
Deposit Mineralogy
Located in San Juan, Argentina, the Los Azules deposit consists primarily of secondary copper mineralization (supergene zone of predominantly chalcocite), with minimal oxide copper content. Additionally, there is a deeper primary copper (hypogene zone of predominantly chalcopyrite with some zones of significant bornite).
Metallurgical Testing Phases
Preliminary results from the Phase 1 program along with historical metallurgical testing at Los Azules were used to support the 2023 Preliminary Economic Assessment (PEA), which proposed an environmentally friendly heap leach alternative to a conventional copper concentrator. The testing program is now advancing with two additional phases (2 & 3) currently underway to support the Feasibility Study (FS). Drilling activities related to the current study work started in 2021 and are continuing into 2024. The leach testing protocols are based on conventional bio-leaching methods used extensively in commercial applications for supergene copper mineralization. The current phases, 2 & 3, are being conducted at SGS Chile and Alfred H. Knight (ASMIN Industrial Limitada) laboratories, both located in Santiago, Chile.
The Phase 1 program was initiated using drill core from drilling programs completed prior to 2021, but not older than 2015, for a total of 21 column tests. Started in 2022, Phase 1 has now been completed and final results received. Preliminary results of this work and prior historical leach testing information were used for the PEA metallurgical assumptions.
The Phase 2 program utilizes drill core from the 2022-2023 drilling campaign and focuses on deposit-wide variability testing, leaching protocol optimization and scalability. A total of 34 column tests are in progress, with results expected in Q2 2024.
The Phase 3 program is also started, utilizing additional drill core material from the ongoing 2023-2024 drilling program. Phase 3 testing is focusing on the material of the initial 5-year mine plan, as delineated in the PEA. A total of 33 additional column tests are planned as part of this final confirmatory testing program, with results anticipated in Q4 2024.
The combined metallurgical programs comprise a total of 88 column tests to be used for the FS metallurgical design basis and geo-metallurgical model.
Copper assaying is conducted using a sequential method to determine the relative amounts of acid soluble (CuAS) and cyanide soluble (CuCN) copper mineralization (oxides and secondary sulfides). When combined, these two partial assay methods are generally considered readily soluble copper (CuSOL), extractable with conventional heap leaching technologies. Copper assayed that does not report to these two partial assay methods is classified as residual copper (CuRES) and is considered copper that requires additional time or is potentially not recoverable with conventional heap leaching technologies.
The finalized results from the Phase 1 metallurgy program for tests completed at minus ½” and ¾” crush sizes confirmed that soluble copper (CuSOL) component recovery is 100% for all leachable resources. The information in Figure 1 below shows the minus ¾” (19 mm) test results. The PEA envisions a minus ¾” crush size for the heap leaching feed in the commercial application.
Figure 1 – Soluble Copper Recovery Kinetics
The recovery results for the residual copper (CuRES) component shown in Figure 2 indicated an average recovery of 25%, an increase of 10% from the 15% preliminary recovery assumption used in the PEA. The additional residual copper recovery when applied to the entire resource increases the overall average recovery from 72.8% to 76.0%.
Figure 2 – Residual Copper Recovery Kinetics
Figure 3 below illustrates the increase in potential copper production throughout the mine life, attributable to the improved recovery, in comparison with the PEA assumptions. The initial two production years do not show additional recovered copper, as the design capacity of the electrowinning plant considered in the PEA is fully utilized.
Figure 3 – Copper Cathode Production (PEA & Revised Model)
The sulfuric acid consumption has also been updated with the Phase 1 final results. The averaged net sulfuric acid consumption reported in the PEA was 18 kilograms per ton of ore processed. The finalized Phase 1 testing now indicates a reduction of 8.3% to 16.5 kilograms per ton. The primary reason for the reduction of acid consumption is minimizing excess acid in the leaching solutions and operating the columns at a pH closer to 2.0 pH than the historic column work at 1.2 pH, which minimizes acid consumption by excess unmineralized gangue material dissolution. This lowered acid requirement may also improve the project economics, both NPV and IRR, by reducing the operating costs for copper produced and increasing revenue from the same tonnes mined.
Bioleaching Summary
Copper bioleaching has been a commercially applied technology at altitudes similar to the Los Azules site and as much as 1,000 meters higher for several decades, in multiple locations around the world. Testing is conducted in conventional leach test columns by inoculation of the columns with naturally occurring bacterial ferrooxidans and thiooxidans prior to introduction of the leach solution. Bacterial cultures for the inoculum were sourced from the testing laboratories and adapted to the Los Azules leach material. Ferrooxidans convert the ferrous iron in solution to ferric iron, while thiooxidans convert the sulfur produced in the copper sulfide leaching activity to sulfuric acid/sulfate. Ferric iron is the key chemical component necessary for leaching of copper sulfide material. Bioactivity in the tests is monitored by measurement of the ferrous/ferric ratios and electrochemical oxidation potential in the leaching solutions.
ABOUT MCEWEN COPPER
McEwen Copper is a well-funded, private company which owns 100% of the large, advanced-stage Los Azules copper project, located in the San Juan province, Argentina. McEwen Copper is a 47.7% owned private subsidiary of McEwen Mining, which is listed on NYSE and TSX under the ticker MUX.
Los Azules is being designed to be distinctly different from conventional copper mines, consuming significantly less water, emitting much lower carbon levels and progressing to be carbon neutral by 2038, being powered by 100% renewable energy once in operation. The project’s recently updated Preliminary Economic Assessment (PEA) projects a long life of mine, low production costs per pound, a short payback period, high annual copper production, and an after-tax IRR of 21.1%.
ABOUT MCEWEN MINING
McEwen Mining is a gold and silver producer with operations in Nevada, Canada, Mexico and Argentina. In addition, it owns approximately 47.7% of McEwen Copper, which owns the large, advanced stage Los Azules copper project in Argentina. The Company’s goal is to improve the productivity and life of its assets with the objective of increasing the share price and providing a yield. Rob McEwen, Chairman and Chief Owner, has a personal investment in the company of US$220 million. His annual salary is US$1.”
The McEwen Mining press release appears to be reviewed and verified by a Qualified Person (as that term is defined by National Instrument 43-101 – Standards of Disclosure for Mineral Projects) and the procedures, methodology and key assumptions disclosed therein are those adopted and consistently applied in the mining industry, but no Qualified Person engaged by TNR has done sufficient work to analyze, interpret, classify or verify McEwen Mining’s information to determine the current mineral resource or other information referred to in its press releases. Accordingly, the reader is cautioned in placing any reliance on the disclosures therein.
“We are pleased that significant developments on the advancement of the Los Azules Copper Project towards feasibility have led to the increased Stellantis holdings in McEwen Copper as a strategic partner of this large copper, gold and silver project. In February 2023, Stellantis invested ARS $30 billion, and with additional investment of ARS $42 billion made after the new preliminary economic assessment (PEA) publication, has a total investment of ARS $72 billion. An aggregate of US $65 million in McEwen Copper was also invested by Rio Tinto’s Venture Nuton in 2022 and 2023,” stated Kirill Klip, TNR’s Chief Executive Officer. “TNR Gold’s vision is aligned with the leaders of innovation among automakers like Stellantis, whose aim is decarbonizing mobility, and mining industry leaders such as Rob McEwen, whose vision is ‘to build a mine for the future, based on regenerative principles that can achieve net zero carbon emissions by 2038’.
“The green energy rEVolution relies on the supply of critical metals like copper; delivering “green copper” to Argentina and the world will contribute to the clean energy transition and electrification of transportation and energy industries.
“Strong team performance is accelerating the McEwen Copper Los Azules program. The Los Azules Project PEA results highlighted the potential to create very robust leach project, while reducing environmental footprint, and greater environmental and social stewardship sets the Project apart from other potential mine developments.
“It’s also very encouraging to see an updated independent mineral resource estimate that has increased significantly.
“Together with Nuton, McEwen Copper is exploring new technologies that save energy, water, time and capital, advancing Los Azules towards the goal of the leading environmental performance. The involvement of Rio Tinto with its innovative technology, may also accelerate realizing the enormous potential of the Los Azules Project.
“Los Azules was ranked in the top 10 largest undeveloped copper deposits in the world by Mining Intelligence (2022). TNR Gold does not have to contribute any capital for the development of the Los Azules Project. The essence of our business model is to have industry leaders like McEwen Mining as operators on the projects that will potentially generate royalty cashflows to contribute significant value for our shareholders.”
ABOUT TNR GOLD Corp.
TNR Gold Corp. is working to become the green energy metals royalty and gold company.
Our business model provides a unique entry point in the creation of supply chains for critical materials like energy metals that are powering the energy rEVolution, and the gold industry that is providing a hedge for this stage of the economic cycle.
Our portfolio provides a unique combination of assets with exposure to multiple aspects of the mining cycle: the power of blue-sky discovery and important partnerships with industry leaders as operators on the projects that have the potential to generate royalty cashflows that will contribute significant value for our shareholders.
Over the past twenty-eight years, TNR, through its lead generator business model, has been successful in generating high-quality global exploration projects. With the Company’s expertise, resources and industry network, the potential of the Mariana Lithium Project and Los Azules Copper Project in Argentina among many others have been recognized.
TNR holds a 1.5% NSR Royalty on the Mariana Lithium Project in Argentina, of which 0.15% NSR royalty is held on behalf of a shareholder. Ganfeng Lithium’s subsidiary, Litio Minera Argentina (“LMA”), has the right to repurchase 1.0% of the NSR royalty on the Mariana Project, of which 0.9% is the Company’s NSR Royalty interest. The Company would receive CAN$900,000 and its shareholder would receive CAN$100,000 on the repurchase by LMA, resulting in TNR holding a 0.45% NSR royalty and its shareholder holding a 0.05% NSR royalty.
The Mariana Lithium Project is 100% owned by Ganfeng Lithium. The Mariana Lithium Project has been approved by the Argentina provincial government of Salta for an environmental impact report, and the construction of a 20,000 tons-per-annum lithium chloride plant has commenced.
TNR Gold also holds a 0.4% NSR Royalty on the Los Azules Copper Project, of which 0.04% of the 0.4% NSR royalty is held on behalf of a shareholder. The Los Azules Copper Project is being developed by McEwen Mining.
TNR also holds a 7% net profits royalty holding on the Batidero I and II properties of the Josemaria Project that is being developed by Lundin Mining. Lundin Mining is part of the Lundin Group, a portfolio of companies producing a variety of commodities in several countries worldwide.
TNR provides significant exposure to gold through its 90% holding in the Shotgun Gold porphyry project in Alaska. The project is located in Southwestern Alaska near the Donlin Gold project, which is being developed by Barrick Gold and Novagold Resources. The Company’s strategy with the Shotgun Gold Project is to attract a joint venture partnership with a major gold mining company. The Company is actively introducing the project to interested parties.
At its core, TNR provides a wide scope of exposure to gold, copper, silver and lithium through its holdings in Alaska (the Shotgun Gold porphyry project) and royalty holdings in Argentina (the Mariana Lithium project, the Los Azules Copper Project and the Batidero I & II properties of the Josemaria Project), and is committed to the continued generation of in-demand projects, while diversifying its markets and building shareholder value.
On behalf of the Board of Directors,
For further information concerning this news release please contact Kirill Klip +1 604-229-8129
Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
Cautionary Statement Regarding Forward-Looking Information
Except for statements of historical fact, this news release contains certain “forward-looking information” within the meaning of applicable securities law. Forward-looking information is frequently characterized by words such as “plan”, “expect”, “project”, “intend”, “believe”, “anticipate”, “estimate”, “will”, “could” and other similar words, or statements that certain events or conditions “may” or “could” occur, although not all forward-looking statements contain these identifying words. Specifically, forward-looking statements in this news release include, but are not limited to, statements made in relation to: TNR’s corporate objectives, and future potential transactions being considered by the Special Committee and the Board. Such forward-looking information is based on a number of assumptions and subject to a variety of risks and uncertainties, including but not limited to those discussed in the sections entitled “Risks” and “Forward-Looking Statements” in the Company’s interim and annual Management’s Discussion and Analysis which are available under the Company’s SEDAR+ profile on www.sedarplus.ca. While management believes that the assumptions made and reflected in this news release are reasonable, should one or more of the risks, uncertainties or other factors materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described in forward-looking information. In particular, there can be no assurance that: TNR will enter into one or more strategic transactions, partnership or a spin-out, or be able to complete any further royalty acquisitions or sales of royalty interests, or portions thereof; debt or equity financings will be available to TNR; or that TNR will be able to achieve any of its corporate objectives. TNR relies on the confirmation of its ownership for mining claims from the appropriate government agencies when paying rental payments for such mining claims requested by these agencies. There could be a risk in the future of the changing internal policies of such government agencies or risk related to the third parties, in future, challenging the ownership of such mining claims. Given these uncertainties, readers are cautioned that forward-looking statements included herein are not guarantees of future performance, and such forward-looking statements should not be unduly relied on.
In formulating the forward-looking statements contained herein, management has assumed that business and economic conditions affecting TNR and its royalty partners, McEwen Mining Inc., Ganfeng Lithium and Lundin Mining will continue substantially in the ordinary course, including without limitation with respect to general industry conditions, general levels of economic activity and regulations. These assumptions, although considered reasonable by management at the time of preparation, may prove to be incorrect.
Forward-looking information herein and all subsequent written and oral forward-looking information are based on estimates and opinions of management on the dates they are made and are expressly qualified in their entirety by this cautionary statement. Except as required by law, the Company assumes no obligation to update forward-looking information should circumstances or management’s estimates or opinions change."