Australian Rare Earths Completes Pilot Recovery of Rare Earths

Australian Rare Earths (ASX:AR3) has advanced its pilot-scale operations at the Koppamurra project by successfully producing a mixed rare earth hydroxide (MREOH) intermediate. This milestone follows continuous heap leach recovery tests conducted at the Australian Nuclear Science and Technology Organisation facility in Sydney. The company reported that the initial processing cycle achieved target rare earth recovery rates, generating a concentrated product from the leach solution as expected.

The pilot program utilized approximately eight tonnes of ore in the first of four planned heap leach column cycles. This input volume yielded around 5,000 litres of pregnant leach solution, which was subsequently processed through a continuous three-stage precipitation circuit. AR3 confirmed full recovery of rare earth elements from the solution into the MREOH solid, marking a significant step in demonstrating the complete processing flowsheet at pilot scale.

Pilot data supports feasibility study design

Managing Director Travis Beinke stated that generating this engineering and operating data is critical for the design phase of the project’s Definitive Feasibility Study. The pilot operations are scheduled to continue until December, focusing on validating precipitation, thickening, filtration, and washing circuits. These tests provide the necessary operational parameters to transition from pilot scale to definitive project design.

The produced MREOH will be further refined into mixed rare earth oxide samples. AR3 intends to provide these representative samples to prospective offtake partners for qualification purposes. This process allows potential customers to assess the material quality before committing to long-term supply agreements, thereby de-risking the commercial viability of the final product.

Future campaigns target larger solution volumes

Further MREOH precipitation campaigns are planned for the remainder of the pilot period. These subsequent cycles aim to process approximately 28,000 litres of pregnant leach solution from the heap leach columns. The continued generation of these concentrated intermediates will solidify the technical foundation for the Koppamurra project’s production capabilities.

The ability to continuously recover rare earths from leach solutions and produce a concentrated intermediate is viewed by AR3 as a key de-risking milestone. This progress supports the company's trajectory toward producing its final MREO product. As reported by GN auto stocks/materials: rare earths, this development underscores the operational readiness of the Koppamurra processing model.