Virgilite

General Information:
 Chemical Formula:
LixAlxSi3-xO6
 Composition:
(Molecular Weight = 183.17 gm)
Lithium 1.89 % Li
Aluminum 7.37 % Al
Silicon 38.33 % Si
Oxygen 52.41 % O 
 Empirical Formula:
Li0.5Al0.5Si2.5O6
 IMA Status:
Approved IMA 1978
Physical Properties:
 Color:
colorless.
 Density:
2.46
 Diaphaniety:
Transparent
 Hardness:
5.5-6 - Knife Blade-Orthoclase
 Streak:
white
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