Australia-listed critical minerals company American Rare Earths has further defined an execution plan for pilot plant processing for its Halleck Creek project, in Wyoming, in the US.

The pilot plant programme has been structured in three stages – milling and sizing; mineral separation and concentration; and leaching, impurity removal and oxide refining. The first two stages will be undertaken in Wyoming and the final stage in Saskatchewan, Canada.

American Rare Earths will process ore which has already been extracted from the Halleck Creek site and stockpiled in Laramie, Wyoming. Milling and sizing will then be undertaken by Western Research Institute in Laramie.

That will be followed by mineral separation and concentration at DISA Technologies’ Casper, Wyoming, facility. The pilot plant will use DISA’s patented High-Pressure Slurry Ablation technology to enhance mineral liberation at coarser particle sizes.

Thereafter, a GradePro reflux classifier and induced roll magnetic separators will be used to perform primary mineral separation and secondary concentration, producing an allanite-rich mineral concentrate for final treatment.

The final stage of the pilot plant programme will be undertaken by the Saskatchewan Research Council (SRC), where the mineral concentrate generated in Wyoming will be processed through leaching, impurity removal and oxide refining to produce high-purity separated rare earth oxide.

SRC and American Rare Earths’ engineering consultants, Tetra Tech, will engineer this stage of the pilot plant based on a prefeasibility study flowsheet.

American Rare Earths notes that SRC facility is almost identical in process configuration, albeit on a smaller scale, to the type of downstream processing facility American Rare Earths intends to eventually build in Wyoming as Halleck Creek advances toward commercial development.

The data generated during the pilot campaign will be used to further develop the necessary design criteria for the advancement of the commercial plant and mine.

“This is a massive step forward for the company. The pilot plant and production of pre-production rare earth oxide were previously expected to take several years. This defined pilot pathway now materially shortens the timeline and positions the company to deliver outcomes within months.

“We are laser focused on accelerating the largest US domestic resource of total rare earth elements towards production,” says American Rare Earths CEO Mark Wall.

He adds that, by combining front-end processing in Wyoming with proven downstream refining infrastructure, the company expects to materially shorten the timeline to produce pre-production rare earth oxide, validate the broader process flowsheet and generate material for downstream evaluation and strategic engagement.

“The company believes this staged pilot approach materially derisks execution by using available facilities, specialised operators and installed or ordered equipment, while preserving the strategic objective of developing a full Wyoming-based rare earth project over time,” he comments.