REE are extracted from three principal sources:
hard-rock deposits (i.e. carbonatites and alkaline igneous rocks)
heavy mineral sands, and
ion adsorption clays
Rare earth oxide production by country 1992-2020. Data source: BGS World Mineral Production.
Global production from hard-rock deposits is dominated by China. However, there are hard-rock mines outside of China including Mount Weld in Australia, Mountain Pass in the USA and Lovozero in Russia. Production of REE from ion adsorption deposits is also heavily concentrated in southern Chinese provinces, but recent changes in environmental legislation has prompted Chinese companies to source REE from similar deposits in Myanmar. Production from heavy mineral sands is dominated by India and Madagascar, but the volume of production is much lower than from other deposit types. Irrespective of deposit type global primary supply of REE is dominated by China and increasingly constrained as Chinese internal demand starts to outstrip domestic supply.
The diversity of REE-bearing deposits requires a variety of mining and processing techniques to be used for their exploitation. Because REE are typically exploited as by-products alongside the extraction of other metals, these will dictate the economics of the operation and the type of mining used. At most mines, beneficiation (i.e. processing of the raw ore to remove gangue minerals) generally occurs on site to produce a REE mineral concentrate that can be shipped for further processing. The exploitation of unconventional REE-ore minerals (e.g. eudialyte, allanite, etc.) will require new methods of beneficiation and processing, as there are currently no commercial-scale processes for REE-bearing minerals other than bastnäesite, monazite, xenotime and loparite. Over the past decade there has been a marked diversification in global REE supply, with China, which dominated mine production of rare earth oxides (REO), dropping it's market share from >95% in 2010 to 68% in 2020.