The transition to a carbon-free economy requires substantial amounts of the critical rare earth elements, for which demand is likely to outstrip supply in coming decades. Vast amounts of rare earths are present in the mine waste of some copper-gold mines, but cannot be economically extracted. This project aims to use molten alkali salts to reprocess mine waste, and transform the rare earths to a readily exploitable form. This project expects to create a scalable industrial separation process to be implemented in existing mines, with the separated ore used as input for extraction. A benefit of this project is the unlocking of a previously inaccessible Australian rare earth resource, comparable in size to the largest deposits globally.