Can AR3’s Low-Risk MREO Process Disrupt China-Dominated Rare Earth Supply?

A Significant Metallurgical Milestone

Australian Rare Earths Limited (ASX – AR3) has announced a major advancement in its Koppamurra Rare Earths Project with successful metallurgical testwork producing a high-purity Mixed Rare Earth Oxide (MREO). This achievement marks a critical step in establishing a commercially viable, low-risk processing pathway from ionic clay ore to a marketable rare earth intermediate.

The testwork employed conventional oxalate precipitation technology, achieving an exceptional 99.9% recovery of rare earth elements from solution while effectively rejecting impurities. The resulting MREO product is projected to grade 98.6% rare earth oxides plus yttrium oxide by weight, a purity level that is highly attractive for downstream separation and end-use markets.

Strategic and Market Implications

The rare earth assemblage in the Koppamurra MREO is notably rich in magnet rare earth elements such as neodymium and praseodymium, alongside yttrium, gadolinium, samarium, and lutetium. These elements are increasingly subject to China’s tightened export controls, underscoring the geopolitical significance of AR3’s supply option. The oxalate precipitation route also offers a simpler and more cost-effective downstream purification process compared to the mixed rare earth carbonate flowsheets pursued by many western ionic clay projects.

Managing Director Travis Beinke highlighted the importance of this development, stating it provides a scalable, transportable, and low-impurity product that aligns with global demand for secure and diversified rare earth supply chains. The company is actively engaging with potential downstream customers, signalling strong market interest in the high-quality MREO product.

Technical Pathway and Next Steps

The metallurgical program included a bulk heap leach campaign producing a pregnant leach solution, which was then processed through oxalate precipitation to yield the MREO. The calcination step, a well-established industrial process, converts the oxalate intermediate into the final oxide form, removing carbon-oxygen compounds and water to yield a stable product.

Alongside the preferred MREO pathway, AR3 also confirmed the technical viability of producing a mixed rare earth carbonate (MREC) as an alternative product, though current focus remains on optimising the MREO route. A comprehensive optimisation program is underway in collaboration with the Australian Nuclear Science and Technology Organisation (ANSTO), aiming to refine reagent dosing, impurity control, and recovery rates ahead of the Pre-Feasibility Study.

Positioning for the Clean Energy Transition

With global supply chains tightening and export controls expanding, AR3’s progress at Koppamurra positions it as a geopolitically relevant supplier of critical rare earths essential for clean energy technologies. Supported by government grants and partnerships with advanced materials manufacturers, the company is advancing towards pilot plant operations and commercial-scale production, reinforcing its role in diversifying the rare earth supply landscape.