Cobalt: historical information
Minerals containing cobalt were of value to the early civilisations of Egypt and Mesopotamia for colouring glass deep blue.
Cobalt was announced to be an element by Georg Brandt about 1739 (or possibly 1735). He had been trying to demonstrate that the blue colour of glass was because of a new element, cobalt, rather than bismuth, an element often found in the same locations as cobalt.
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