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1.                 From The Elements (07Nov00):
                   
   
   
                   
                     
   cerium
   Symbol: Ce
   Atomic number: 58
   Atomic weight: 140.12
   Silvery metallic element, belongs to the lanthanoids. Four natural
   isotopes exist, and fifteen radioactive isotopes have been identified.
   Used in some rare-earth alloys. The oxidized form is used in the glass
   industry. Discovered by Martin .H. Klaproth in 1803.