Tausonite

Strontium titanate is an oxide of strontium and titanium with the chemical formula SrTiO3. It is a centrosymmetric ferroelectric material with a perovskite structure. It was long thought to be a wholly artificial material, until 1982 when its natural counterpart—discovered in  Siberia and named tausonite—was recognised by the  IMA. Tausonite remains an extremely rare mineral in nature, occurring as very tiny crystals. Its most important application has been in its synthesized form wherein it is occasionally encountered as a diamond simulant, in precision optics, in varistors, and in advanced ceramics.
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General Information:
 Chemical Formula:
SrTiO3
 Composition:
(Molecular Weight = 183.50 gm)
Strontium 47.75 % Sr
Titanium 26.09 % Ti
Oxygen 26.16 % O 
 Empirical Formula:
SrTiO3
 IMA Status:
Approved IMA 1982
Physical Properties:
 Cleavage:
None
 Color:
brown red, gray, dark red, red, or reddish brown.
 Density:
4.88
 Diaphaniety:
Translucent to Opaque
 Hardness:
6-6.5 - Orthoclase-Pyrite
 Luster:
Adamantine
 Streak:
brownish white
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