Name of the Project
Halleck Creek rare earths project.

Location
Central Laramie Mountains, Wyoming, US.

Project Owner/s
Wyoming Rare (USA) Inc (WRI), a subsidiary of American Rare Earths (AAR).
 
Project Description
The project comprises the Cowboy State mine in American Rare Earths’ southern land holdings and the Overton mountain resource area in the north.

It is planned that project will be developed in two phases. Phase 1 is the Cowboy State mine, which has a 20-year life-of-mine (LoM) and a three-million-tonne-a-year base-case processing rate. Phase 2 would involve the broader Halleck Creek development on federal land and minerals, with a potential mine life of more than 80 years. 

Under the Phase 1 base case, average neodymium/praseodymium equivalent production is estimated at 2 790 t/y over the LoM. 

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
Under the three-million-tonne-a-year base case for the Cowboy State mine, the updated scoping study indicates an after-tax net present value, at a 10% discount rate, of $558-million and an internal rate of return of about 24%. 

Capital Expenditure
Initial capital expenditure for the Cowboy State mine is estimated at $456-million, including contingency. 

Planned Start/End Date
Construction is expected to take 2.5 years to complete.

Latest Developments
AAR has started with its 2026 exploration drilling programme at the Cowboy State mine within the Halleck Creek rare earths project.

The programme marks the start of feasibility-level drilling at what is believed to be the US’s largest known rare earths deposit on a total rare-earth oxides basis.

AAR will use the drill results to help inform a definitive feasibility study on Halleck Creek. Drilling is focused on Cowboy State mine and its Red Mountain area owing to its potential for cost-efficient openpit mining.

The company appointed Boart Longyear to drill up to 3 050 m, or 10 000 ft, across 19 holes on the Red Mountain prospect, which is expected to be concluded in mid-July.

In turn, Dahrouge Geological Consulting will manage the exploration programme and provide on-site geological logging and sample preparation services for the duration of the drill campaign.

AAR expects the campaign to generate more than 1 000 core samples for assay, with some remaining core due to be retained for geotechnical, hydrological, environmental and metallurgical testwork.

Key Contracts, Suppliers and Consultants
Jaye Pickarts (pilot plant process lead and metallurgical engineering consultant); Western Research Institute (milling and sizing); DISA Technologies (mineral separation and concentration); Saskatchewan Research Council (leaching, impurity removal and oxide refining); Tetra Tech (engineering support for the final pilot plant stage); and Boart Longyear (drilling programme); and Dahrouge Geological Consulting (exploration programme management and provide on-site geological logging and sample preparation services for the duration of the drill campaign).

Contact Details for Project Information
American Rare Earths, tel +61 2 8054 9779 or email info@americanree.com.