The positive news keeps flowing from American Rare Earths’ Halleck Creek project, this time in the form of the latest round of metallurgical test work – a crucial indicator of costs and supply chain opportunities for rare earths projects.

Just over a week ago American Rare Earths (ASX:ARR) announced new assays from its Wyoming project showing high rare earth grades from surface to 175.5m. That depth was 75.5% over that drilled for the maiden drill campaign of 100m last year and the basis for the project’s globally significant exploration target of 1.01 to 1.27 billion tonnes.

ARR is now looking forward to announcing a significant maiden JORC resource by the end of March 2023, once the final assay results have been returned.

The most recent test work builds off results from previous analysis on Halleck Creek ore showing that a simple, less costly and more environmentally sensitive process can produce a rare earth concentrate and maximise the recovery of the project’s high-value magnet rare earth elements Neodymium and Praseodymium.

Also referred to as “the twins” because they can be so difficult to separate, Neodymium and Praseodymium, or Nd and Pr, are essential ingredients for the permanent magnets used in clean energy infrastructure such offshore wind turbines, EV charging stations and EVs themselves. They’re also needed to make our everyday electronic devices work.

The technical stuff

The initial tests using Wet High Intensity Magnetic Separation (WHIMS) yielded 90.5% Total Rare Earth Oxide (TREO) recovery for 1.18% TREO (11,200ppm). This is a highly encouraging upgrade factor of 3.3 relative to the original feed material with an impressive 71.7% of waste material being rejected at an early stage of the process. Those results are consistent with previous mineralogy test work results that showed the target rare earth mineral Allanite can be easily liberated.

As with ARR’s previous test work, this most recent round was conducted under the guidance of Wood PLC, one of the world’s leading engineering companies.

What all that means

In simple terms, the coarser grind will result in lower operating costs as less energy will be consumed through the primary grinding circuit.

CEO and Managing Director, Mr Chris Gibbs, commented:

“These latest metallurgical test results are extremely encouraging and continue to advance the Halleck Creek Project a step closer towards commercial reality.

“Metallurgy is the key to any mining project and these recent results continue to exceed our expectations. This simple process flow sheet translates to lower operating costs, and reduced capital investment and environmental impact. Having low thorium and uranium penalty elements are a huge advantage for this project to produce a low-cost rare earth concentrate.”

“From a mining perspective, the latest drill assay results indicate a large scale, low-cost open pit mining operation. Together with these metallurgical results, Halleck Creek is shaping up to be rare earth equivalent of a major copper/gold porphyry deposit, comparable to the likes of major mines operated by Freeport-McMoRan and Rio Tinto.”

Critical partnerships

As well as reducing costs and boosting its ESG profile, the almost negligible levels of radioactive elements makes ARR’s ore more attractive to its top-tier R&D partners including the US Department of Energy Innovation Hub, the Critical Minerals Institute and the Critical Materials Institute. That means ARR is involved in US government supported efforts aim to transform the rare earths industry into a cleaner and more sustainable one, while offering supply chain security for the US,

Ore from ARR’s La Paz project has a very similar profile to that from Halleck Creek. The Arizona project has a current JORC Resource estimate of 170MT, with drilling targeting ~742-928MT of rare earths mineralised rocks to establish a JORC resource for the SW area.




This article was developed in collaboration with American Rare Earths, a Stockhead advertiser at the time of publishing.

This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.