The Tonopah Flats Lithium Project in Nevada stands as one of the largest identified claystone lithium deposits in the United States. Developed by publicly traded American Battery Technology Company (ABTC), the project is set to play a key role in domestic lithium production, supporting the growing demand for battery-grade materials.
Project Overview and Milestones
ABTC began geological exploration at Tonopah Flats and announced an inferred resource. Subsequent project assessments and feasibility studies laid the foundation for long-term development.
The U.S. Federal Permitting Council designated Tonopah Flats as a Transparency Priority Project under the FAST-41 Permitting Dashboard, expediting coordinated federal approvals for both mining and refinery operations. ABTC published a pre-feasibility study (PFS) outlining a projected 45-year life of mine (LoM) for the southern portion of the property.
The PFS estimates initial and pre-production capital expenditure of approximately $2 billion during the initial development period, with an additional $205.6 million in sustaining capital over the remaining mine life. Pilot operations are expected to begin soon, with commercial production anticipated afterward and full capacity projected subsequently, contingent on market conditions.
Location and Geology
The Tonopah Flats Lithium Project is situated in the southeastern part of Big Smoky Valley, about 11 km northwest of Tonopah town, spanning Esmeralda and Nye counties. The property covers 517 unpatented federal lode mining claims, totaling around 4,322 hectares (10,680 acres).
Geologically, the site lies within an alluvial basin flanked by the San Antonio Mountains to the east and Monte Cristo Mountains to the west. The surface layer consists mainly of quaternary alluvial deposits of silt, sand, and gravel, averaging less than 15 meters thick, which overlays the Miocene Siebert Formation—a mix of claystone, volcanic conglomerate, sandstone, siltstone, and tuff. Lithium mineralization is concentrated in the claystone members of the Siebert Formation.
Reserves and Mining Method
Tonopah Flats hosts proven and probable reserves of 559.85 million tonnes at an average lithium grade of 805 ppm, equating to 451,000 tonnes of lithium or 2.73 million tonnes of lithium hydroxide monohydrate (LHM).
ABTC plans to operate Tonopah Flats as an open-pit mine, using drilling, limited blasting, loading, and hauling. The soft rock conditions mean only 5% of clay requires blasting. Overlying alluvium will be stockpiled for reclamation. Pit design features 10m bench heights, 45° bench faces, 34° inter-ramp slopes, and 30m haul roads. Average ore production aligns with refinery throughput, targeting 12.4 million tonnes per annum over the mine life. Tailings will be dry-stacked and used for pit backfill.
Processing and Recovery
The Tonopah Flats plant is designed to handle 11.9 million tonnes of claystone per year. Refinery construction is planned in three phases, initially producing 5,000 tpa of battery-grade LHM, scaling to 12,500 tpa, and eventually reaching 30,000 tpa.
The processing workflow includes comminution and screening, extraction, impurity removal, crystallization, and lithium hydroxide conversion. Lithium is separated from claystone, purified through precipitation and membrane processes, and converted to LHM via electrochemical crystallization. Tailings from extraction and off-gas handling will be temporarily stored in dry-stack impoundments before in-pit placement.
Infrastructure and Logistics
Tonopah Flats is accessible via U.S. Highways 6 and 95, with internal unpaved roads connecting different parts of the site. The nearest airport and rail connections are in Reno, approximately 266 km northwest. High-voltage transmission lines provide power access, while municipal water from Tonopah town meets exploration and production requirements. Additional water needs would follow Nevada regulatory permitting.
Financing and Partnerships
ABTC has secured significant support from the U.S. Department of Energy, including grants for extraction technology demonstration and lithium hydroxide facility construction. Low-cost debt financing of $900 million was approved through the U.S. Export-Import Bank.
Key contractors include Barr Engineering for technical reporting and pre-feasibility studies, Black & Veatch for plant design and construction, RESPEC for resource estimation under SEC S-K 1300 standards, and True North Drilling for core sampling. ABTC also collaborates with DuPont Water Solutions, the University of Nevada, Reno, and Argonne National Laboratory to advance the commercial deployment of the lithium production facility.
Strategic Importance
The Tonopah Flats Lithium Project represents a major step toward U.S. domestic battery mineral production, strengthening supply chain security for electric vehicles and renewable energy storage. By combining large-scale reserves with advanced processing technology, Tonopah Flats is poised to become a cornerstone of North America’s sustainable energy future.
