On a technical note for those that don't know yet - from investor preso 13/3/23
This might get a little boring but however knowledgeable, so get your chemistry set out and give it a go
The testing of solvents will be a very technical task but maybe not for the people that do it daily
What they are saying already is that the Stallion deposit will be in a more efficient economic class to leach than most others out there, in turn delivering the products will be more profitable
Typical REE-bearing ores usually contain REEs as either carbonate ((REE)(CO3)F) or phosphate ((REE)PO4) minerals, which require processing with concentrated sulfuric acid (H2SO4), hydrochloric acid (HCl), or sodium hydroxide (NaOH) at elevated temperatures to achieve extraction.3There exists a third class of REE-ores typically in southern China and other subtropical areas that is called ionic clay. Ionic clays are formed by the chemical weathering of REE-containing parent rocks, resulting in the mobilization of REE ions, and the enrichment of the REEs onto the clay surface by ion adsorption.4In the majority of ionic clays reported so far, for example the ones from southern China, REEs are mostly surface-adsorbed, rather than being locked within the bulk of mineral phases; hence, they can be desorbed under relatively mild conditions by heap-leaching clay mounds or by in-situ leaching of the clay with mild lixiviant solutions and collecting the REE-rich runoffOnce the REEs are desorbed from the ionic clay and extracted into the solution, they can be separated from the solution and purified via a variety of methods such as selective precipitation, solvent extraction, and ion-exchange, then calcined to obtain either a mixed rare earth oxide (REO) product, or individual separated REOs.10
There are several benefits in sourcing REE from ionic clays, such as low mining and pre-treatment costs, low reagent and energy consumption, low environmental/safety risks, low co-extraction of hazardous radioactive materials, and high recovery of valuable heavy REEs
(20min delay)