# American Rare Earths advances Cowboy State Mine project in Wyoming

American Rare Earths, through subsidiary Wyoming Rare (USA), released an updated scoping study for the Cowboy State Mine project in Wyoming, the first development phase of the Halleck Creek project. The proposed openpit operation would produce about 2,500 t/y of neodymium/praseodymium oxide, with initial capital estimated at $900 million. Commissioning is modelled for 2030, followed by commercial production in 2031.

- Type: Investment
- Announced: 2026-09-30
- Where: Wyoming, USA, United States
- Value: $900.0M
- Starts operating: 2030
- Status: announced
- Capacity: 2,500 t/y of neodymium/praseodymium oxide
- Products: neodymium/praseodymium oxide
- Sectors: [Mining Equipment](https://endata.com/sectors/mining-equipment.md)

## Companies

- [American Rare Earths](https://endata.com/companies/95033.md)
- [Wyoming Rare (USA)](https://endata.com/companies/95034.md) (partner)

## Sources

- [miningweekly.com](https://www.miningweekly.com/article/cowboy-state-mine-project-us-2026-11-06), 2026-11-05: "The prefeasibility study, recovery optimisation and permitting work are continuing."

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Data from Endata (https://endata.com/). Announcements are summarized from public sources and may be incomplete; check the linked originals.