Chemical Element: calcium

(Modern Latin: chemical element; from Latin, calx, calcis, lime; metal)

Chemical-Element Information

Symbol: Ca
Atomic number: 20
Year discovered: 1808

Discovered by: Sir Humphry Davy (1778-1829), an English chemist.


  • Compounds such as lime (calcium oxide) were prepared by the Romans in the first century under the name calx.
  • Literature dating back to about 975 A.D. notes that plaster of Paris (calcium sulphate, dehydrated gypsum) was useful for setting broken bones.
  • Other calcium compounds used in early times include limestone (calcium carbonate).
  • Calcium metal was not isolated until 1808.
  • After learning that Berzelius and Pontin prepared calcium amalgam by electrolyzing lime in mercury, Sir Humphry Davy was able to isolate the impure metal.
  • He did this by the electrolysis of a mixture of lime and mercuric oxide.
  • Calcium metal was not available in large amounts until the beginning of the 20th century.

Name in other languages:

French: calcium

German: Calcium

Italian: calcio

Spanish: calcio


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.