Davreuxite

General Information:
 Chemical Formula:
MnAl6Si4O17(OH)2
 Composition:
(Molecular Weight = 635.17 gm)
Manganese 8.65 % Mn
Aluminum 25.49 % Al
Silicon 17.69 % Si
Hydrogen 0.32 % H 
Oxygen 47.86 % O 
 Empirical Formula:
Mn2+Al6Si4O17(OH)2
Physical Properties:
 Cleavage:
[100] Good
 Color:
cream white or light pink.
 Density:
3.15
 Hardness:
2-3 - Gypsum-Calcite
 Luster:
Silky
 Streak:
white
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