The rare earth elements (REEs) are mined from hard-rock sources and from sources formed by weathering at the Earth's surface. The main hard-rock sources are carbonatite and alkaline igneous rocks, in which REEs are found in a wide range of minerals, although currently they are only extracted from monazite, xenotime, fluorcarbonates and loparite.
Much research is being undertaken to expand the range of minerals from which we will be able to extract REEs in the future. The main weathered sources of REEs are ion adsorption clays, weathered carbonatites and mineral sands. China is the main global producer of REE ores and concentrates, but a number of other REE mines have opened in recent years.
