American Rare Earths begins Halleck Creek drilling campaign to support DFS
American Rare Earths Ltd (ASX:ARR, OTCQX:ARRNF) has launched its 2026 drilling program at the Halleck Creek rare earths project in Wyoming, marking the start of feasibility-level drilling designed to underpin a definitive feasibility study (DFS) at what the company describes as the largest known...
American Rare Earths Ltd(ASX:ARROTCQX:ARRNF) View Price & Profile American Rare Earths begins Halleck Creek drilling campaign to support DFS
Last updated: 21:54 26 May 2026 EDT, First published: 21:40 26 May 2026 EDT
American Rare Earths Ltd (ASX:ARR, OTCQX:ARRNF) has launched its 2026 drilling program at the Halleck Creek rare earths project in Wyoming, marking the start of feasibility-level drilling designed to underpin a definitive feasibility study (DFS) at what the company describes as the largest known rare earth deposit in the United States on a total rare earth oxide (TREO) basis.
The drilling campaign is focused on the Cowboy State Mine area within Halleck Creek and comes as the company continues advancing the project amid growing US efforts to strengthen domestic critical minerals supply chains and reduce reliance on Chinese rare earth imports.
American Rare Earths chief executive officer Mark Wall said the company was pushing ahead with multiple development workstreams in parallel while reviewing and optimising its pre-feasibility study.
“Commencing this drilling program is an important and exciting step as we continue to accelerate Halleck Creek,” Wall said.
“While we are actively reviewing and optimising the pre-feasibility study, we are moving ahead in parallel with feasibility-stage drilling so that we do not lose time.”
Core from initial drill hole location PL5-RM-005.
Feasibility drilling underway
The company has engaged drilling contractor Boart Longyear to complete up to about 3,050 metres of HQ core drilling across 19 holes on Red Mountain within the Cowboy State Mine area. Dahrouge Geological Consulting will oversee the exploration program, including geological logging and sample preparation.
Drilling began on May 13 and is expected to continue through to mid-July. The campaign is anticipated to generate around 1,045 core samples for assay, while remaining core will be retained for geotechnical, environmental, hydrological and metallurgical studies supporting the DFS process.
All drill holes will also undergo geophysical logging, including optical and acoustic televiewer surveys, aimed at supporting detailed geomechanical analysis for future mine design.
ARR noted that about 12 of the planned holes would be drilled from platforms constructed near the crest of Red Mountain, with helicopter support required to transport equipment and core boxes due to the rugged terrain. Average hole depths are expected to reach about 125 metres, with some extending as deep as 300 metres.
Exploration staging area.
Targeting higher-grade zones
Nine of the planned core holes are positioned on top of Red Mountain and are targeting higher-grade zones expected to fall within the first five years of planned mining identified in the pre-feasibility study pit shells. The company said these holes were intended to support future ore reserve estimation as part of the DFS.
Another 10 holes are planned around the base of Red Mountain to test additional higher-grade mineralisation identified through earlier channel sampling and geological mapping.
Key objectives of the campaign include upgrading resources within planned early mining areas to Measured and Indicated classifications, testing mineralisation extensions at depth and to the west of previous drilling, and collecting additional material for metallurgical and hydrogeological studies.
Core samples will be photographed, logged and split onsite before being sent to ALS Global for assay work, with residual material stored for future specialised testing.
Proposed hole locations.
Building momentum at Halleck Creek
The drilling program follows a series of recent steps by American Rare Earths to advance Halleck Creek towards development, including work on pilot plant pathways, engineering studies and corporate preparations for a planned Nasdaq listing.
The company has increasingly positioned Halleck Creek as a strategic US domestic rare earths project capable of supplying materials critical for defence technologies, electric vehicles, advanced manufacturing and broader energy transition applications.
Located on Wyoming state land, the project is expected to benefit from open-pit mining methods and streamlined permitting processes in what the company described as a mining-friendly jurisdiction.
American Rare Earths said ongoing exploration across both state and federal lands continued to highlight the broader scale potential of the Halleck Creek district as the US looks to establish a more secure domestic rare earth supply chain.