Hafnon

General Information:
 Chemical Formula:
HfSiO4
 Composition:
(Molecular Weight = 270.57 gm)
Hafnium 65.97 % Hf
Silicon 10.38 % Si
Oxygen 23.65 % O 
 Empirical Formula:
Hf(SiO4)
 IMA Status:
Approved IMA 1974
Physical Properties:
 Cleavage:
[???] Indistinct
 Color:
colorless, brownish, or yellow.
 Density:
6.97
 Diaphaniety:
Transparent
 Hardness:
7.5 - Garnet
 Luster:
Vitreous - Adamantine
 Streak:
gray white
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