Occurrence and Production of Tungsten |
Occurrence |
Tungsten is found in the minerals wolframite (iron-manganese tungstate, FeWO4/MnWO4), scheelite (calcium tungstate, CaWO4), ferberite and hubnerite. There are important deposits of these minerals in China (with about 80% world share), Russia, Austria and Portugal, reports the British Geological Survey. The metal is commercially produced by reducing tungsten oxide with hydrogen or carbon. |