The maiden preliminary economic assessment (PEA) for the Tonopah Lithium Claims (TLC) project, in Esmerelda, Nevada, has demonstrated the project’s potential to become a substantial, long-life producer of low-cost lithium carbonate (LCE).

At 99.5% LCE purity, TLC has the potential to producer either battery-grade LCE or lithium hydroxide, with minimal additional refining, reports American Lithium CEO Simon Clarke.

The PEA base case envisions an initial 4.4-million-tonne-a-year processing throughput, expanding to 8.8-million tonnes a year. The alternative case is identical, but with added production of high-purity magnesium sulphate as a byproduct.

Magnesium sulphate is an increasingly important fertiliser add-on product with a large and growing market.

“A significant portion of the processing work has been done to prefeasibility levels as we believe this will help us move quickly through the next phases of development,” said Clarke.

The PEA base case envisions a mine and processing production plan that will produce 1.46-million tonnes of LCE over 40 years. Operating costs are estimated at $7 443/t of LCE, inclusive of power credits.

The TLC project will require an initial $819-million and total capital expenditure of $1.43-million. The aftertax payback period is 3.8 years.

American Lithium reports an aftertax internal rate of return (IRR) of 27.5% and a net present value (NPV), using an 8% discount, of $3.64-billion at $20 000/t LCE.

“In this PEA, we showcase a long mine-life utilising only the highest-grade sections of the deposit, with the potential for additional production ramp-up and mine life utilising our mid-grade and lower grade sections.

“Not only are the economics very strong for high-purity lithium production, but TLC also has the potential to produce high-purity magnesium sulphates as by-products for agriculture and other end-uses. As shown in the PEA, even assuming conservative pricing, these byproducts can add significant economic value. At the same time, we have focused our work on ensuring we continue to minimise environmental impacts and water usage in the mining, processing and production of lithium from TLC,” said Clarke.

The alternative case has an NPV of $5.2-billion and an IRR of 36%.