Axel REE advances ISR rare earth extraction with Woolrich field trial in Brazil

Woolrich Deposit Takes Centre Stage for ISR Testing

Axel REE Limited (ASX:AXL) is moving beyond laboratory testing with the selection of its Woolrich ISR Deposit within the Caladão Project in Brazil as the site for its inaugural in situ recovery (ISR) rare earth elements (REE) field trial. This marks a critical step in Axel’s ambition to commercialise a low-impact, low-cost magnesium sulphate (MgSO₄) leaching process targeting ionic clay-hosted rare earth mineralisation.

The Woolrich deposit, part of the broader 572 million tonne inferred rare earth resource at Caladão, boasts soluble total rare earth oxide (TREO) grades averaging 464 ppm. This is strikingly comparable to the 486 ppm soluble TREO grade at the operating Gerik ISR REE mine in Malaysia, a rare benchmark in the sector. Moreover, Woolrich’s magnet-rich REE assemblage, with around 42% magnetic rare earth oxides (MREO) and 40% neodymium-praseodymium (NdPr), signals a premium product potential that Axel hopes to capitalise on.

Field Trial Designed to Bridge Lab Results and Real-World Operations

The field trial will be conducted within a carefully selected 2-hectare area characterised by favourable geology, including low-relief topography and a well-developed lateritic regolith over coarse granite, which supports permeability and hydraulic containment essential for ISR operations. A multidisciplinary team spanning geology, hydrogeology, engineering, environmental science, and specialist consulting is being assembled to design and execute the programme.

The trial aims to generate field-scale pregnant leach solution (PLS) under realistic operating conditions, providing critical data on permeability, reagent consumption, recovery behaviour, and impurity management. This PLS will then be supplied to Core Resources in Australia for downstream processing into mixed rare earth carbonate (MREC), effectively testing the full value chain from extraction to saleable product.

These efforts build on Axel’s recent metallurgical breakthroughs, including over 96% magnetic rare earth recovery via hydrochloric acid leaching reported earlier this year, which supports a dual-path development strategy combining ISR and acid leach processing. The Woolrich trial complements this by focusing on the modular ISR approach, which aims to reduce capital intensity and surface disturbance compared to traditional mining.

Comparative Strengths and Next Steps

Woolrich’s metallurgical profile stacks up well against peers in the ionic clay and ISR space, with soluble TREO and MREO proportions competitive with projects like Brazil’s EMA and Australia’s Colossus. Notably, the deposit includes strategic rare earths such as dysprosium and terbium, contributing to basket value.

Axel’s near-term plans include completing ongoing column leach tests at Core Resources to refine wellfield design, conducting hydrogeological and geotechnical assessments, installing the wellfield, and commencing MgSO₄ injection. The trial’s success will underpin further technical studies and resource integration at Caladão Area B.

This field trial announcement follows Axel REE’s recent acceleration of ISR trials at Caladão, leveraging its unique gallium resource to position itself distinctively in the critical minerals sector. The company’s strategy to validate low-impact ISR mining aligns with growing market interest in sustainable rare earth supply chains.