
Cobalt: Cobalt is a chemical element which is found in the earth's crust only in a chemically combined form. Blue-pigmented cobalt has been used for thousands of years for jewelry and bling because of its rich blue color. It was discovered in 1739 by a Swedish chemist. It is commonly used to make alloys and magnetic materials. surprisingly, it is also essential that we have a certain amount of cobalt in our diet, which we can gather from vitamin B12.