Cobalt - Co

General Information

Discovery

Cobalt was discovered by G. Brandt in 1735 in Stockholm, Sweden.

Appearance

Cobalt is a lustrous, silvery-blue, hard metal.

Source

Cobalt is found in the minerals cobaltite, smaltite and erythrite. Important ore deposits are found in Zaire, Morocco and Canada. There is evidence that the floor of the north central Pacific Ocean may have cobalt-rich deposits.

Uses

Cobalt metal is used in electroplating because of its attractive appearance, hardness and resistance to oxidation. It is alloyed with iron, nickel and other metals, and used in jet turbines and gas turbine generators.

Cobalt salts have been used for centuries to produce brilliant blue colours in porcelain, glass, pottery and enamels.

Radioactive cobalt-60 is used in the treatment of cancer.

Biological Role

Cobalt is an essential trace element, and forms part of the active site of vitamin B12. Cobalt salts in small doses have been found to be effective in correcting mineral deficiencies in certain animals. Cobalt in large doses is carcinogenic. Radioactive artificial cobalt-60 is an important gamma-ray source, and is used extensively as a tracer and radiotherapeutic agent.