Symbol: Sb
Atomic number: 51
Atomic weight: 121.75
Element of group 15. Multiple allotropic forms. The stable form of
antimony is a blue-white metal. Yellow and black antimony are unstable
non-metals. Used in flame-proofing, paints, ceramics, enamels, and rubber. Attacked by oxidizing acids and halogens. First reported by Tholden in 1450.