Cobalt is obtained primarily as a by product of the mining and processing of copper and nickel ores. cobalt ores include cobaltite [(Co, Fe)AsS], erythrite [(Co3(AsO4)2·8H2O)], fukuchilite ( Cu3FeS8), glaucodot [(Co, Fe)AsS], linnaeite [(Co, Ni)3S4], skutterudite [(Co,Ni,Fe)As3], and smaltite [(Co, Fe, Ni)As2]. Cobalt is extracted as a by-product of nickel and copper concentration through pyrometallurgical, hydrometallurgical and electrolytic processes.
Cobalt contributes corrosion resistant and hardness if alloyed with other metals and when used in electroplating. The major uses of cobalt is preparing metal alloys. Cobalt-60 with a half-life of 5.3 years is a gamma ray source when used in radiotherapy and sterilization. It is used as a catalyst in the petroleum production and chemical synthesis. Cobalt molybdate catalyst is active in desulfurization of petroleum. Cobalt is combined with many other elements including chlorine, sulfur, nitrogen and oxygen. In addition to a common state +1, the most prevalent oxidation states of cobalt are +2 and +3. Cobalt compounds are used as pigments in glass and ceramics. It is used as a drying agent for paints, varnishes and inks and animal feeds. It is a raw material to make other cobalt salts.