It is one milestone finding a large, potentially commercial rare earth element (“REE”) deposit, and an all together separate milestone to crack the metallurgy to produce saleable product. This has been the focus on Avalon Rare Metals (TSX:AVL, OTCQX:AVARF) who have not only been investing in drilling out the Nechalacho rare earth element project – one of the largest undeveloped deposits of its kind outside of China - near Thor Lake in the North-West Territories, Canada, but also focusing on the process required to separate the various rare earth elements and metals.
Last year Avalon reported a new flotation process designed to produce an REE mineral concentrate, and this morning, the company reported that it had crafted a new hydrometallurgical process to further upgrade the concentrate to a chemical concentrate, most likely to be a rare earth carbonate.
“Avalon has now successfully established a hydrometallurgical process methodology, proven numerous times in the laboratory, for extracting the REE out of the mineral concentrates, bringing them into solution so that they can be upgraded by solvent extraction and precipitated as a chemical (carbonate) concentrate,” the company stated.
Avalon has been focusing on the “Basal Zone” layer at Nechalacho, which contains an uncharacteristically high amount of heavy rare earth elements (samarium to lutetium, including yttrium) hosted in fergusonite and zircon along with light rare earth elements (“LREE”)(lanthanum to neodymium) hosted in bastnaesite, synchisite, monazite and allanite.
Around half of the heavy rare earth elements are hosted in zircon, and also contain rare earth metals tantalum, niobium and zirconium.
Metallurgical testwork, directed by John Goode, has led to development of a flotation process that concentrates the zircon and fergusonite as well as the LREE mineral phases and associated columbite (a niobium tantalum oxide ore mineral), Avalon reported.
The testwork to date has resulted in an average rare earth element, niobium, tantalum and zircon recovery in the region of 80% at a mass pull of 18%. Additional work to refine the process is underway, and will include a five tonne bulk sample of the ore, which is planned for this summer.
“After mineral concentrate production, the next step is mineral cracking, which involves breaking down the rare metal bearing minerals,” Avalon added. “Avalon has tested a number of methods and has settled on a two-stage process of sulphuric acid bake followed by caustic crack of the residue as the most technically and cost-effective methodology for this particular suite of REE-bearing minerals. This method results in approximately 90-95% of the rare metals being brought into solution. “
What does this all mean? For the moment, though positive, it is difficult to gauge the weight of the news, but investor’s will not have to wait much longer to put all the results into a perspective. A pre-feasibility study, which will include hydrometallurgical plant design work, capital and operating costs, is due for completion this spring.
Shares in Avalon climbed 2% this morning in response to the update.
Disclosure: no position