Axel’s initial tests recover ionic REEs and gallium from Caladão

Axel REE’s initial metallurgical testing recovers ionic REEs along with gallium from its Caladão project in Brazil.

No cramming was needed for Axel REE to ace initial testing on the REE and gallium potential of its Caladão project. Pic: Getty Images

• First-pass tests at ANSTO has confirmed ionic REEs are present at the project along with recoverable gallium

• High value Magnet REE (MREO) head grades recovered amongst global leaders

• Company developing simple, two-stage heap leach process for low-cost, environmentally-friendly operations

Special Report: Initial metallurgical testwork has proved that Axel REE’s Caladão project in Brazil hosts ionic and non-ionic rare earths along with gallium mineralisation and all are readily recovered using straightforward leaching techniques.

The testwork completed by ANSTO leached ionic adsorption clay (IAC) rare earths using standard ammonium sulphate leaching at pH4 with similar recoveries using sodium chloride under the same conditions.

Importantly for Axel REE (ASX:AXL), this returned strong (up to 52%) recoveries of the high-value magnet rare earths neodymium, praseodymium, dysprosium and terbium in first pass tests, which mirrors initial recovery efficiencies reported from other global IAC REE deposits.

It also confirms that a significant portion of REEs at Caladão are adsorbed onto clays allowing recovery by simple leaching.

Additionally, acid leach tests on samples from diamond holes DDH-018 and DDH-036 and in a composite with gallium returned promising recoveries of IAC REE and REE from the primary and secondary REE minerals as well as gallium.

“We are genuinely excited by these first-pass results, which confirm Caladão’s potential to host both ionic and non-ionic rare earths, as well as gallium - all shaping to be recoverable through straightforward leaching techniques,” AXL non-executive chairman Paul Dickson said.

“Factoring in the high-grade nature of our REE and gallium intercepts to date, the recovered values of MREO and gallium from these high first-pass head grades is in line with world-class projects.

“The use of low-cost reagents like NaCl and AMSUL, combined with the absence of complex mining requirements, positions Axel incredibly well to develop a low-capex, low-opex operation with strong environmental credentials.

“With the growing global focus on supply chain diversification outside China, we believe Caladão has the foundations to become one of the largest and most strategically significant rare earth and gallium projects globally.”

Metallurgical results

ANSTO tested 39 composites from holes DDH-018 and DDH-036, which are 2km apart in the Caladão project, using leaching by 0.5 Mol ammonium sulphate at pH4 at ambient temperature.

This achieved recoveries of up to 52% magnet REEs. Notably, 249ppm MREO was leached from an interval of 18m averaging 632ppm MREO, which represents a high-grade nominal extracted MREO compared to other IAC projects.

Additional tests were conducted on four selected samples from DDH-036 for leaching at higher acidity to improve REE recovery.

Magnet extraction from composite 35 in hole DDH-036 had a steady increase in recovery under acid leaching, achieving 28% recovery after five days, opening a new front to recover REE from non-ionic REE mineralisation at the Caladão project.

Gallium was also extracted in acid leaching with recoveries enhanced with leach duration.

The results also suggest there’s gallium supergene enrichment following the same behaviour.

AXL believes that defining the mineralogical association of gallium in this oxidised horizon is crucial to working out a potential concentration method from which it can be extracted with low costs.

A dedicated gallium production stream will complement the extraction of REEs and enhance overall project economics.

Next steps

AXL is continuing development of a simple, two-stage heap leach process for low capex and opex operations that will significantly reduce the environmental footprint.

It has also secured a partnership with Centro de Tecnologia Mineral – a Brazilian federal research centre dedicated to technological innovation for the mineral industry – to carry out further metallurgical investigations for gallium and REE.

Meanwhile, its ANSTO partnership continues to progress metallurgical testwork aimed at utilising heap leach to optimise previous leach recoveries, impurity removal and precipitation tests for REE.

Additionally, a maiden JORC resource for Area A is expected in late July or early August 2025.

This article was developed in collaboration with Axel REE, 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.

Originally published as Axel’s initial tests recover ionic REEs and gallium from Caladão