Nafertisite

General Information:
 Chemical Formula:
Na3(Fe++,Fe+++)6(Ti2Si12O34)(O,OH)7·2(H2O)
 Composition:
(Molecular Weight = 1,530.61 gm)
Sodium 4.51 % Na
Titanium 6.26 % Ti
Iron 21.89 % Fe
Silicon 22.02 % Si
Hydrogen 0.38 % H 
Oxygen 44.95 % O 
 Empirical Formula:
Na3Fe2+4.5Fe3+1.5Ti2Si12O39.25(OH)1.75·2(H2O)
 IMA Status:
Approved IMA (Dana # Added)
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
green or dark grass green.
 Density:
2.7
 Diaphaniety:
Transparent
 Hardness:
2-3 - Gypsum-Calcite
 Luster:
Vitreous - Silky
 Streak:
white
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