Natalyite

General Information:
 Chemical Formula:
Na(V+++,Cr+++)Si2O6
 Composition:
(Molecular Weight = 226.36 gm)
Sodium 10.16 % Na
Vanadium 16.88 % V 
Chromium 5.74 % Cr
Silicon 24.81 % Si
Oxygen 42.41 % O 
 Empirical Formula:
NaV3+0.75Cr0.25Si2O6
 IMA Status:
Approved IMA
Physical Properties:
 Cleavage:
[110] Distinct
 Color:
yellow green or light green.
 Density:
3.55
 Diaphaniety:
Transparent
 Hardness:
7 - Quartz
 Luster:
Vitreous - Silky
 Streak:
green
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