Cobalt is a metallic element with a melting point of 1768 K and boiling point of 3200 K. It was first discovered in 1735 by Georg Brandt and has a density of 8.9 g/cm3. Cobalt is used to produce blue pigments and impart a blue tint to glass and ceramics. It is also used to make magnetic, wear-resistant and high-strength alloys and the radioactive cobalt-60 isotope is used as a radioactive tracer and in gamma ray production.

1. 27
Co
COBALTO- COBALT
MASS: 58.933195 u
1s2
2s2
2p6
3s2
3p6
4s2
3d7
MELTING POINT: 1768 K
BOILING POINT: 3200 K
DENSITY: 8.90 g·cm−3
DISCOVERY: 1735 (Georg Brandt)
Cobalt-based blue pigments (cobalt blue) have been used since ancient
times for jewelry and paints, and to impart a distinctive blue tint to glass.
Today, some cobalt is produced specifically from various metallic-lustered
ores, of copper and nickel mining. Cobalt is used in the preparation
of magnetic, wear-resistant and high-strength alloys. Cobalt silicate and
cobalt(II) aluminate give a distinctive deep blue color
to glass, smalt, ceramics, inks... Cobalt occurs naturally as only one stable
isotope, cobalt-59. Cobalt-60 is a commercially important radioisotope, used
as a radioactive tracer and in the production of gamma rays.