What is cobalt used for?

Cobalt is used in magnets, ceramics, special glasses, and tools. It is a key alloying element in certain steels and alloys known as MCrAlY where it is alloyed with chromium, aluminum and yttrium and where M is nickel or cobalt. The element when reacted with fatty acids is also a drier for oil based paints and varnishes.

Cobalt is also essential to all animals, including humans. It is a key constituent of cobalamin, also known as vitamin B12. Trace amounts of cobalt are available in most diets. The presence of 0.13 to 0.30 mg/kg of cobalt in soils markedly improves the health of grazing animals.

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