THE RARE-EARTHS - THEIR MINERALS, PRODUCTION AND TECHNICAL USE

Deposits of rare earth minerals are of magmatic, sedimentary and of metamorphic type. The most important economic mineralizations are the magmatic to hydrothermal bastnaesite deposits of Mountain Pass (USA) and of Bayan Obo (China P. R.), as well as the monazite-bearing coastal placers of Australia, Brazil and India. No shortage in rare earth supply will be faced by the world economy in the next years. China has by far the most important reserves. An increased demand can be observed for individual rare earths of high purity, and for mixtures of specific rare earths.