calcination
    n 1: the conversion of metals into their oxides as a result of
         heating to a high temperature

Calcination \Cal`ci*na"tion\ (k[a^]l`s[i^]*n[=a]"sh[u^]n), n.
   [F. calcination.]
   [1913 Webster]
   1. (Chem.) The act or process of disintegrating a substance,
      or rendering it friable by the action of heat, esp. by the
      expulsion of some volatile matter, as when carbonic and
      acid is expelled from carbonate of calcium in the burning
      of limestone in order to make lime.
      [1913 Webster]

   2. The act or process of reducing a metal to an oxide or
      metallic calx; oxidation.
      [1913 Webster]