Northern Minerals confirms high-purity mixed Rare Earth oxide

THE BOURSE WHISPERER: Northern Minerals (ASX: NTU) has completed metallurgical studies at the company’s Browns Range Heavy Rare Earth Element (HRE) project in northern WA, which it claims has confirmed the project’s ability to produce a high-value, 92 per cent mixed RE oxide.

Northern Minerals said the results have supported preliminary hydrometallurgical studies conducted last year, which indicated the Browns Range mineral concentrate can be processed into a high-value, high-purity mixed RE oxide using conventional unit processing techniques.


Browns Range HRE project – simplified process flowsheet. Source: Company announcement


the ability to produce a mixed RE oxide significantly enhances the value of the Browns Range end product and expands the Company’s marketing options.

“Metallurgy is a critical aspect for any rare earth project, and the results from Browns Range have so far ticked all the boxes,” Northern Minerals managing director George Bauk said in the company’s announcement to the Australian Securities Exchange.

“The positive hydrometallurgical results have now further de-risked the project and now opened the door to a significantly larger and higher value market for our HRE product.”
The company indicated its decision to produce the mixed RE oxide will require a further 12 months to advance the hydrometallurgical test work and pilot plant, with an estimated first production of mixed RE oxide in 2016.

“The Board has considered the results and consulted with end users,” Bauk said.

“The value generated from the enhanced economics and the improved marketability of the product is significant, and warrants the additional time to develop the mixed RE oxide path.

“This pathway to production is supported by the recent $58 million funding package, which will take the project through to the completion of feasibility studies.”

After receiving the result of the earlier testing, Northern Minerals engaged Tenova Mining and Minerals to develop and manage a detailed hydrometallurgical test work program.

The first stage of this program has now been completed with the confirmation test work undertaken at both ALS and Nagrom laboratories in Perth.

Northern Minerals said the results from both laboratories confirmed the Browns Range mineral concentrate can be processed to produce a high-value and high-purity mixed RE oxide.

The key results are:

Extraction efficiency in the acid bake and water leach step exceeded 85 per cent;

The precipitation efficiency of the oxalate precipitation step exceeded 99 per cent;

The product purity of the final calcined exceeded the target of 92 per cent TREO in the mixed RE oxide; and

Heavy Rare Earths dominate the mixed RE oxide.