Yerington Copper Project

The Yerington Copper Project encompasses the historic Yerington and MacArthur open-pit mines, positioned in one of the most promising copper districts in the U.S. With a robust Pre-feasibility Study recently filed, the project is well-advanced and progressing toward development. Lion Copper & Gold (Lion CG) is advancing the site with a modernized mining approach—utilizing existing infrastructure, advanced bioleaching technology, and a mining-friendly regulatory environment to accelerate production timelines.

LCG holds Proven and Probable Reserves of 506.5 million tons at 0.21% CuT, containing 2.14 billion pounds of copper

In addition to the reserves, a Measured and Indicated Resource of 293.3 million tons at 0.18% CuT, containing 989 million pounds of copper and an additional Inferred Resource of 158.1 million tons at 0.14% CuT, containing 443.4 million pounds of copper.

The Project

The Yerington Copper Project offers a rare combination of efficiency, scalability, and strong project economics—positioning it as one of the most attractive emerging copper developments in the U.S. The plan features open-pit mining with both oxide and sulfide heap leach operations, incorporating Rio Tinto’s Nuton™ technology for enhanced copper recovery and efficient onsite production of 99.99% pure LME A-grade copper cathode. Here’s why the Yerington project stands out:

Sizeable and scalable open pit heap leach project

Average annual production of 120 million pounds of refined copper cathode over a 12-year mine life, with a peak of 151 million pounds in Years 5–7.
Proven and Probable Reserves of 506.5 million tons at 0.21% CuT, containing 2.14 billion pounds of copper.
Strong copper recovery performance with an average of 67.4% LOM copper recovery from low-cost heap leaching – 73.2% copper recovery from sulfides using Nuton leach technology and 60% from oxides in a conventional ROM heap leach.
Extensive land holdings include patented and unpatented mining claims as well as private land adjacent to other significant copper deposits.
The Project plans to spend approximately $70M to treat 43,000 acre-feet of Yerington Pit Lake water and release this water to the environment for multiple beneficial stakeholder uses in the Mason Valley.
Benefits of the Project include utilizing disturbed land for mine infrastructure, zero discharge of water from copper processing operations, lower carbon intensity, and efficiently delivering copper cathode directly into U.S. supply chains.

Why Yerington?

The Technology

Pre-Feasibility Study Highlights

In September of 2025, the Company released its Pre-Feasibility Study (PFS)*, confirming the project’s strong economics and scalability. Key findings:

Base Case $4.30/lb copper, Post-Tax NPV (7%) $694 million and 14.6% IRR with payback at 6.7 years.
Initial Capital: $724 million, including mine development, heap leach pads, SX/EW plant, acid plant and related infrastructure.
Base Case NPV-to-Initial Capital Ratio of 0.96.
Operating Costs: Cash cost (C1)¹ of $1.92 per pound of copper.
All-in Sustaining Costs (AISC)¹ of $2.67 per pound of copper.
Base Case Capital Intensity² of $12,044/tpa.

Total cash cost and AISC are non-GAAP measures and include royalties payable.
Initial capital expenditures divided by average annual copper production for mine life

All figures in US Dollars.

*Readers are cautioned that this PFS is preliminary in nature. It includes inferred mineral resources considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves, and there is no certainty the PFS will be realized. Mineral resources that are not mineral reserves do not have demonstrated economic viability. The estimate of mineral resources may be materially affected by environmental, permitting, legal, title, socio-political, marketing, and other relevant issues.
For technical details, see the full report here: 43-101 Pre-Feasibility Study: Yerington Copper Project

Learn more: The Opportunity

Achievement & Momentum

The Yerington Copper Project is built on a rich legacy of copper mining, encompassing the historically operated Yerington and MacArthur open-pit mines. Situated in a historically significant mining district, the project benefits from a well-documented resource base, extensive geological studies, and proven exploration upside.

Lion CG has been actively engaged in Yerington since 2006, advancing exploration, resource development, and strategic partnerships. With the Pre-Feasibility Study now complete (link), our efforts are focused on project permitting and the Definitive Feasibility Study—the final, detailed technical and financial evaluation of the project. Current work includes baseline studies to support permitting, advanced material testing, front-end engineering, and final trade-off analyses.

Key Development Milestones

Extensive Site Evaluations: The Yerington and MacArthur mines have undergone extensive permitting, environmental studies, and operational analyses, enabling us to leverage a wealth of historical mining data to guide future development.
Prefeasibility Study (PFS) Finalized: The detailed Pre-Feasibility Study (PFS) combines extensive technical and operational expertise, supported by thorough data analysis and various trade-off studies for different development scenarios. A conservative capital cost contingency of 24.3% provides a financial buffer. As a brownfields project, existing infrastructure and historical knowledge significantly reduce technical and operational risks, enhancing feasibility and readiness.
Infrastructure Optimization: Evaluating site access, power, transportation, and site logistics for streamlined development.
Environmental & Water Management: Baseline environmental studies and groundwater modeling are underway to assess pit lake dewatering and beneficial water discharge alternatives.

Next Steps

Ongoing baseline studies and permitting will continue towards DFS and district development.Ongoing baseline studies and permitting will continue towards DFS and district development.

Get involved.

If you’d like to learn more about this project opportunity, download the corporate presentation or contact us to set up a conversation.