Chemical Element: cobalt

(German: Kobalt; also Kobolt, a goblin, evil spirit, or malicious sprite; metal)

Chemical-Element Information

Symbol: Co
Atomic number: 27
Year discovered: 1735

Discovered by: Georg Brandt (1694-1768), a Swedish chemist.

  • Minerals containing cobalt were of value to the early civilizations of Egypt and Mesopotamia for coloring glass deep blue.
  • In China, cobalt ores were used to produce the blue colors of the porcelains of the Ming dynasty.
  • Cobalt was announced to be an element by Georg Brandt about 1735 (or possibly 1739).
  • In 1737, a Swedish chemist, Georg Brandt (1694-1768), investigated the blue ore and managed to obtain a metal from it but one that was definitely not copper.
  • He had been trying to demonstrate that the blue color of glass was the result of a new element, called cobalt, rather than bismuth, an element often found in the same locations as cobalt.
  • It puzzled miners that blue mineral resembling copper ore did not yield copper when smelted.
  • The miners assumed that it was copper ore that had been bewitched by kobolds; that is, earth spirits who were thought to be malevolent at times.
  • Brandt gave it the name of the earth spirit, spelling it “cobalt”, and that is still the name of the element.
  • This was the first new element discovered since Brand’s discovery of phosphorus previously in 1669.
  • Since phosphorus is not a metal, cobalt was also the first metal to be discovered that was not known to the ancients or to the medieval alchemists.
  • Brandt was perhaps the first important chemist to be completely free of any alchemical taint, and after him the discovery of new elements has continued until recent times.
  • Cobalt is now being used to impart a blue color to structural glass, pharmaceutical, perfume, and decorative bottles, as well as optical filter glasses.
  • Another principal use is in alloys, particularly in “superalloys”, as those in jet engines.
  • It is also used in the preparation of alloys of high magnetic strength for permanent magnets. and in high-speed tool steels, hot-work tool steels, and high-carbon, high-chromium, and cold-work steels.
  • Small quantities of cobalt salts are used to correct mineral deficiencies in livestock and additives in varnish and inks.

Name in other languages:

French: cobalt

German: Cobalt

Italian: cobalto

Spanish: cobalto

Information about other elements may be seen at this Chemical Elements List.

A special unit about words that include chemo-, chem- may be seen here.