American Rare Earths Ltd. has released an updated scoping study for its Cowboy State Mine in Wyoming, US, expanding the proposed project’s development footprint as it seeks to build a rare earth domestic supply chain for the United States.
The updated study evaluates a larger 4.5 million tonne per annum (mtpa) operation at the project, which represents the initial development phase within the broader Halleck Creek resource. The expanded profile reflects a 50 per cent increase in processing throughput compared to the 2025 base case.
Under the new operational parameters, the mine life extends from 20 to 26 years, targeting average annual production of approximately 2,500 tonnes of neodymium and praseodymium (NdPr) oxide, a 36 per cent increase over previous estimates.
The financial evaluation projects an after-tax net present value (NPV) of US$1.07 billion (AU$1.54 billion) at an 8 per cent real discount rate, with initial capital expenditure estimated at US$900 million, including contingencies.
The project configuration combines open-cut mining and concentration in Wyoming with a dedicated hydrometallurgical refinery.
To advance downstream integration, the company is collaborating with US firm Novex to test the conversion of rare earth oxides into permanent magnet metals, which are critical for electric vehicles, defense, aerospace, and renewable power generation.
“Our ambition is to turn Halleck Creek’s resource scale into a long-term source of rare earth materials for American industry,” said CEO Mark Wall.
“We are now evaluating a mine with 50 per cent greater processing capacity, 36 per cent more annual NdPr oxide production, and a longer operating life than the 2025 base case. That is a substantial platform from which to advance the project.”
American Rare Earths is progressing a pre-feasibility study while advancing recovery optimisation, infrastructure planning, and permitting applications.
Pilot plant testing is underway, with separated rare earth oxides targeted for late Q2 2027. The company is also preparing PCAOB audits to support a potential US listing on the Nasdaq.
“Our focus is on getting the recovery assumptions, plant configuration, infrastructure and execution plan right while those choices can still materially improve project outcomes with minimal additional cost,” said Andrew Conover, Chief Development Officer.
“The objective is a better defined project with appropriate trade-offs considered, and a disciplined pathway towards a development decision.”
