What is Cobalt atom?

     

Cobalt is a chemical element with the symbol Co and atomic number 27.  Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron.  The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.  

     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 but the color was later though to be due to the known metal bismuth.  Miners had long used the name kobold ore (German for goblin ore)  for some of the blue-pigment-producing minerals;  they were so named because they were poor in known metals, and gave poisonous arsenic-containing fumes when smelted.  In 1735, such ores were found to be reducible to a new metal and this was ultimately named for the kobold.  

     Cobalt is primarily used in lithium-ion batteries, and in the manufacture of magnetic wear-resistant and high-stength alloys.  The compounds cobalt silicate and cobalt(II) aluminate(CoAl2O4) give a distinctive deep blue color to glass, ceramics, inks, paints and varnishes.  Cobalt occurs naturally as only one stable isotope, cobalt-59.  Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy gamma rays.