Initial leach testing of samples taken from Victory’s North Stanmore rare earths project near Cue, Western Australia has resulted in strong recoveries of valuable heavy REEs.

Recoveries of up to 63.6% lutetium, 60% dysprosium and 58% terbium were achieved using low-cost ammonia sulphate and weak sulphuric acid at 50 degrees C and low leach times.

The recovery of these REEs is significant as dysprosium and terbium have a combined value of about US$1,070 per kilogram compared to the already valuable magnet REEs neodymium and praseodymium (NdPr), which have a combined value of US$113/kg.

Importantly for Victory Metals (ASX:VMT), the metal recoveries also indicate that a significant portion of the REEs are ionically adsorbed onto clays, which confirms that North Stanmore is a deep “fossil” ionic adsorption clay mineral system that preserves an enrichment profile in the regolith.

Additionally, the presence of 20-50 micron size grains of REE phosphate minerals could be relict from the REE rich source lithology and warrant further investigation.

“This is an instrumental moment for Victory and provides confirmation that the company’s North Stanmore Rare Earth discovery has significantly recovered REE and more importantly high levels of recoverable Dy and Tb,” chief executive officer Brendan Clark said.

“It is important for the market to fully understand the Rare Earth Element sector and that’s why Victory’s technical team ensures that complete REE assay data is reported to facilitate analysts and investors in making informed investment decisions.”

Clark added that the initial metallurgical recoveries have confirmed low ratios of gangue materials such as iron and aluminium that can be costly to remove.

Technical advisor Professor Ken Collerson said the initial metallurgical results show that the extensive regolith hosted REE deposit surrounding the North Stanmore mafic to ultramafic alkaline intrusion contains leachable quantities of HREEs.

“In addition, this highly oxidised deposit exhibits many of the geochemical features characteristic of ionically adsorbed clay REE deposit,” he noted.

“Additional metallurgical studies are in progress and are expected to increase yields particularly of NdPr.”

The low leach times are also important as extended leaching times will result in the need for larger processing plants.

North Stanmore

Recent exploration at North Stanmore had expanded the REE footprint at North Stanmore up to 34km2.

Drilling has returned excellent grades of up to 1,010 parts per million (ppm) total rare earth oxides (TREO) while the testing has resulted in high recoveries of critical and valuable HREE with low levels of acid consumption.

Leach testwork is ongoing with a focus on optimisation of leach parameters, as well as diagnostic leach testing of individual samples.

This diagnostic leach test work will inform geometallurgical variability across the North Stanmore project.




This article was developed in collaboration with Victory Metals, 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.