American Rare Earths Ltd (ASX:ARR, OTCQX:ARRNF) (ASX: ARR, OTCQX: ARRNF, ADR: AMRRY) is advancing its drill program at its flagship Halleck Creek rare earths project in Wyoming as it works to define the next phase of development across its US critical minerals portfolio.
The company said the 2026 field season was centred on Halleck Creek, where drilling is underway at the Cowboy State Mine area to support the project’s feasibility study.
At the same time, American Rare Earths is progressing technical reviews and target-generation work across its broader portfolio, including La Paz in Arizona, Beaver Creek in Wyoming and Searchlight in Nevada.
Halleck Creek drilling underway
At Halleck Creek, American Rare Earths has started a drilling program of up to about 3,050 metres of HQ core across 19 holes on Red Mountain at the Cowboy State Mine.
The program, which began in May, is designed to support future ore reserve estimation, test extensions of mineralisation at depth and to the west of existing drilling, and provide material for geotechnical, hydrogeological, environmental and metallurgical workstreams.
The company said five holes had been drilled to date, with core from completed holes being processed and dispatched for assay.
Assay turnaround is currently expected to be about six weeks due to the busy North American drilling season.
Whole-property assessment to guide expansion
Alongside the drilling, American Rare Earths is continuing its Whole of Property Development Assessment across the broader Halleck Creek land package.
The assessment, awarded in April 2026, is expected to run through to the end of 2026 and is designed to integrate geological, metallurgical, mining and permitting data across the wider project area.
The work is intended to establish a strategic development roadmap beyond the initial Cowboy State Mine plan, including Red Mountain, Overton Mountain and Bluegrass.
American Rare Earths CEO Mark Wall said 2026 was a “pivotal year” for the company as it advanced Halleck Creek through feasibility-stage work while continuing to build its broader US exploration pipeline.
“At Halleck Creek, drilling is now underway to support the Feasibility Study, while the Whole of Property Development Assessment is helping define the longer-term expansion pathway across the broader district,” Wall said.
Portfolio work continues
Beyond Halleck Creek, the company is progressing reviews and field planning at its other US assets.
At Beaver Creek in Wyoming, American Rare Earths plans to carry out additional geological mapping and surface sampling during 2026 to improve geological understanding and strengthen the project database.
Historic work at Beaver Creek returned laboratory assay results of 5.8% to 13.9% total rare earth oxides from grab samples, with NdPr reported at 1.0% to 2.2% of total ore.
The project’s rare earth mineralisation is hosted in allanite-enriched veins, the same host mineral as Halleck Creek.
At La Paz in Arizona, the company is undertaking a comprehensive property assessment focused on the project’s broader multi-commodity potential, including gold, silver, copper, manganese and other non-rare earth critical minerals.
The review includes reinterpretation of historic mapping, drill core and chip relogging, reassessment of geochemical datasets and review of historic geophysical surveys.
In Nevada, the Searchlight Heavy Rare Earths Project remains an early-stage asset about 30 kilometres east of the Mountain Pass mine, the only operating rare earth mine in the United States.
Historic exploration at Searchlight has returned results including up to 6.81% rare earth oxides, although the project has no current mineral resource and has not been drilled by American Rare Earths.
What's ahead
American Rare Earths expects near-term activity at Halleck Creek to focus on completing the current drilling campaign, receiving assays, progressing feasibility workstreams and continuing the Whole of Property Development Assessment through 2026.
Planning for 2027 is expected to be guided by feasibility study requirements, development sequencing and results from current technical programs.
At Beaver Creek, La Paz and Searchlight, the company expects 2026 and 2027 work programs to focus on refining geological understanding, ranking targets and identifying the most effective exploration pathways across the portfolio.