Name       : Cerium
Symbol     : Ce
Atomic #   : 58
Atom weight: 140.12
Melting P. : 798
Boiling P. : 3443
Oxidation  : +3, +4
Pronounced : SER-i-em
From       : Named for the asteroid, Ceres, discovered just two years
             before the element
Identified : Jons Jocob Berzelium and Wilhelm Hisinger in 1803
Appearance : Malleable, ductile, iron-gray metal
Note       : Most abundant of the rare-earth metals
             
[Properties]

  Cerium is a shiny gray, malleable, soft, and ductile metal. It readily
oxidizes in moist air and decomposes rapidly in hot water. The heat of
friction caused by scratching a sample of the pure metal can ignite it.
  Cerium is classified as a lanthanide - a member of the series of 
elements from lanthanum (element 57) through lutetium (element 71). Cerium
is also prominent among the rare-earth elements, which include the 
lanthanide series as well as scandium (element 21) and yttrium (element
39).
  There are four allotropes of cerium, alpha through delta. Most of them
exist at relatively low temperatures:

     - Alpha form, below -172 degrees
     - Beta form, between -172 and -16 degrees
     - Gamma form, between -16 and 726 degrees
     - Delta form, above 726 degrees

  The gamma form is the one that exists under normal environmental
conditions.
