‘Exceeded expectations’: Testwork for Stage 2 production increases total rare earths 20 TIMES at Cummins Range, Australia’s largest undeveloped REE project
Beneficiation testwork to upgrade REEs at Cummins Range are resulting in 20-times the total rare earths. This supports the product strategy to upgrade the RE leach residue from the acid leaching step which separates LFP phosphates from the REs.
Cummins Range is the largest undeveloped rare earths (REE) project in Australia with an indicated and inferred resource of 519Mt @ 0.31% TREO and 4.6% P2O5 (phosphate) for a contained 1.6Mt TREO.
Carbonatite is rare, with only 500 or so known sites in the world. They’re conducive to containing high percentages of rare earths and for RareX, Cummins Range could be the next big REE mine to set itself up in Australia.
The company plans to initiate the project with a low-cost direct shipping ore (DSO) phosphate production for Stage 1 (essentially the overburden) to help fund and de-risk the subsequent stage which transitions the project into a large-scale REE producer.
The latest testwork at Cummins Range has reinforced RareX’s product strategy of upgrading the separated RE residue from the leached lithium iron phosphate (LFP) battery suitable phosphates. The testwork shows a 20x upgrade in TREO and solid recovery performance.
This is in line with its recent scoping study that outlined the delivery of both high-purity phosphoric acid and valuable rare earths to market from a combined mineral concentrate produced at site which is the main, Stage 2, project stage..
RareX is proposing to use the customer’s dilute phosphoric acid leaching to extract the phosphate and leaving the REEs contained within a leach residue.
Beneficiation testwork focused on producing product and product derivative samples for offtake negotiations. If all goes well, RareX will be able to deliver a dual mineral concentrate which will refine to produce both high-grade phosphoric acid suitable for LFP batteries and rare earth concentrates for use in EV magnets.
“The phosphate within apatite and the rare earths within monazite means we can maximise the extraction of both of these highly strategic elements,” RareX CEO James Durrant says.
Tests at Beatou Menrong Fine Materials demonstrated up to a 20x upgrade of total rare earth oxides (TREO) from 1% head grade material with floation recoveries of an impressive 50%.
RareX believes it demonstrates the potential for improved upgrades of the leach residue (which is expected to have a 6% TREO starting grade, much higher than the tests which had a starting grade of only 1%).
Ore feed material containing apatite was used to determine the flotation configuration and reagent solution. Leach residue is expected to perform well with this type of construct and samples are being sent for confirmation testing once bulk flotation and leach trials are complete.
In the best result, an REE concentrate of 22.5% TREO grade was achieved from a feed grade of 1% at a recovery of 48.74%.
RareX says “to be able to achieve an upgrade of over 20x into concentrate from the ROM feed is considered to be very encouraging” and are in line with other developing rare earth deposits of similar head grades.
RareX CEO James Durrant says the team consider the test results to be very encouraging.
“While these tests were undertaken on run-of-mine ore – which is not our proposed development pathway for Cummins Range – the run-of-mine (ROM) results will directly inform the flotation regime requirements for the rare earth leach residue after we’ve stripped away the pure apatite and fed it into the LFP supply chain,” Durrant says.
“The fact that the tested processing regime can concentrate rare earths in ROM material by 20-fold has exceeded the expectations of our metallurgists.
“Importantly, this metallurgical approach is also directly applicable to the leach residue material, which has already been chemically upgraded to six times the original TREO head grade and has less mineralogical complexity – meaning it should deliver even better float performance with higher recoveries.
“The results provide continued support to the proposed Cummins Range product strategy for the processing of Stage 2 combined monazite-apatite phosphate concentrate.
“Our met team is now assembling product samples, both to ensure that we understand process performance for our and our offtakers’ facilities and also to provide real product sample and derivative product materials in support of ongoing offtake negotiations.”
Further testwork continues as RareX looks to replicate and improve on the results, while also working toward the production of mineral concentrate and product samples.
Additionally, results from this year’s drill program are expected soon and will support another resource update for Cummins Range.
This article was developed in collaboration with RareX, 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.