American Rare Earths reaches MREO milestone at Halleck Creek
MiningJan 28, 2026
United States | Australia
American Rare Earths produced Mixed Rare Earths Oxide (MREO) from Halleck Creek ore using an updated mineral processing flowsheet during the December 2025 quarter, marking a key technical milestone.
The MREO was generated by precipitating a mixed rare earth oxalate from a purified pregnant leach solution, then calcining the precipitate. Neutralisation testwork to remove impurities addressed historical challenges with allanite-hosted mineralisation and supported continuity in the hydrometallurgical program.
Beneficiation optimisation progressed alongside an updated preliminary flowsheet that incorporates recent testwork; further optimisation and evaluation are planned. An updated Mineral Resource Estimate for the Cowboy State Mine area reclassified 68.4 Mt into the indicated category, strengthening the geological basis for ongoing studies.
Corporate moves included the appointment of Mark Wall as CEO and an expanded partnership with Tetra Tech to pursue US government funding for mine-to-magnet capabilities. A University of Wyoming-led project will explore potential byproducts and applications from Halleck Creek extraction.
Near-term priorities for the March quarter are integrating metallurgical and beneficiation results into the prefeasibility study, planning demonstration plant options, continuing environmental and hydrological studies for permitting, and preparing 27 permitted infill drill holes.
Cash at December 31 was A$23.98 million, with A$2.4 million in listed financial assets; subsequent asset sales added further proceeds.
American Rare Earths Limited (ASX: ARR) is a Sydney-based mineral exploration and development company focused on advancing large-scale rare earth projects in the United States to establish a secure, domestic supply chain for critical minerals.