Cobalt / CAS 7440-48-4

Cobalt, atomic number 27, is a hard, glossy silver gray metal.
Cobalt has been used to make glass products blue since the Bronze Age, and has also been found in relics from various countries, including Egypt, Persia, and China!

The word ‘Cobalt’ comes from the German word ‘Kobold,’ which means ‘a fairy in the mountains’ and ‘a fairy in the ground’.
The miners in Germany tried to make silver from ore, but it didn’t go well, so they were afraid it was because of the mountain’s regularity.
And then the discovery of a beautiful new element in this ore led to the call cobalt.
In 1735, Swedish chemist Brandt succeeded in separating Cobalt from the cobalt ore for the first time and named it Cobalt after its mineral name.
But Brandt and many other chemists thought it was a compound of iron and arsenic, and they didn’t consider it an element. It wasn’t until 1780 that the same Swedish chemist Berryman recognized Cobalt as a new element.

Cobalt is stable in the air and does not react to water but slowly dissolves in dilute acids. The addition of cobalt oxide to molten glass turns blue, which has already been used to color glass and pottery since ancient times. Also, many artists have long preferred cobalt blue, and Leonardo da Vinci was one of them. Cobalt blue is an oxide of cobalt and aluminum that is widely used as a blue pigment.