ASX- and LSE-listed Pensana Rare Earths has successfully produced a mixed rare earth carbonate (MREC) rich in neodymium and praseodymium (NdPr) from testwork that is currently under way at its Longonjo rare earth project, in Angola.

Industry experts Wood Group and Nagrom have successfully developed a flowsheet to produce a particularly high-grade MREC with NdPr comprising 33.5% of the total rare earths content.

This was based on testwork performed at a metallurgical laboratory in Perth, Australia.

Pensana explains that MREC is a high-purity and high-value product, with a broad market and range of applications.

The resultant MREC from the testwork is higher quality than the concentrate product contemplated in Pensana’s preliminary feasibility study and compares favourably with the main products currently being produced and sold in China.

The company continues with pilot plant work and metallurgical testwork to finalise the preferred processing route, as well as to provide data for engineering and production cost estimates for the project’s bankable feasibility study (BFS).

Pensana says a comprehensive update on the BFS will be reported towards the end of October. Two of the circuits will be required to run for longer to bring the testwork results up to the required reporting standards for the study, which will enable the finalisation of the report in due course.

The BFS will report whether there is potential for the project to be brought online as the first major rare earths mine in over a decade and to offer a sustainable supply of MREC at a time when there is growing concern around the provenance of the rare earths supply chain.

The BFS will also be underpinned by the project’s updated mineral resource estimate published in September.

The project contains 313-million tonnes at 1.43% total rare earth oxides, including 0.32% NrPr for 4.4-million tonnes of total rare earth oxides, including 990 000 t of measured, indicated and inferred NdPr resources.

CEO Tim George comments that the project’s potential has been further confirmed by it being able produce a marketable higher-value NdPr MREC, since the market for this carbonate is substantially larger than that of a concentrate and is potentially not limited to China.

“We are now in a position to start discussions with potential offtake parties in Japan, Korea and Europe in addition to the wide range of potential customers in China.

“Importantly the combination of this value-adding step with the excellent infrastructure, not least the available hydro-electric power supply, will enable us to develop Longonjo as one of the world’s most sustainable rare earth suppliers on the critical magnet metal supply chain,” he adds.

With the recent resource upgrade and ongoing financial backing of the Angola Sovereign Wealth Fund, the company is confident about its ability to rapidly develop the project.