AR3 Doubles Leach Rates, Hits 70% Rare Earth Recovery at Koppamurra

Optimising Koppamurra’s Rare Earth Extraction

Australian Rare Earths Limited (ASX, AR3) has unveiled a significant metallurgical milestone at its Koppamurra Rare Earths Project in South Australia and Victoria. Recent testwork has demonstrated a clear pathway to accelerate heap leach processing by doubling irrigation rates, effectively halving the time required to extract magnet rare earth elements such as neodymium, praseodymium, dysprosium, and terbium.

This optimisation has resulted in approximately 70% recovery rates for these critical elements, a marked improvement that could materially enhance project economics and throughput. The company also reports that halving the magnesium sulphate reagent concentration in the leach solution does not compromise extraction efficiency, indicating potential for reduced operating costs and simplified chemical management.

Implications for Project Scale and Cost

Faster leach kinetics mean that AR3 can achieve target production rates with a smaller heap leach footprint, translating into lower capital expenditure and operational costs. The ability to reduce reagent intensity without sacrificing recovery further strengthens the project's cost profile. These advances come amid a comprehensive metallurgical optimisation program conducted in partnership with the Australian Nuclear Science and Technology Organisation (ANSTO), which is preparing for pilot plant operations scheduled for mid-2026.

CEO Travis Beinke emphasised the significance of these results, highlighting the simplification and optimisation of the Koppamurra flowsheet. He noted that the outcomes build on previous successes, including impurity rejection techniques and the production of a high-purity mixed rare earth oxide product, reinforcing confidence in the project's technical foundation.

Strategic Importance Amid Global Supply Challenges

The high recoveries of strategically important rare earths such as yttrium, gadolinium, and samarium; elements increasingly subject to export controls from China; underscore Koppamurra’s potential role in diversifying Western supply chains. The project has already secured a $5 million Australian government grant and benefits from collaboration with global industrial materials manufacturer Neo Performance Materials.

With the Pre-Feasibility Study (PFS) underway, these metallurgical improvements provide a stronger technical and economic basis for advancing the project. The pilot plant results expected later this year will be critical in validating scale-up assumptions and refining the flowsheet further.

Looking Ahead

AR3’s ongoing optimisation efforts include refining reagent dosing, pH control, and impurity management to balance recovery and cost. The company’s strategic positioning in both rare earths and uranium markets, combined with government and industry partnerships, positions it well to meet growing demand for critical minerals essential to the clean energy transition.