Walthierite

General Information:
 Chemical Formula:
Ba0.5Al3(SO4)2(OH)6
 Composition:
(Molecular Weight = 443.78 gm)
Barium 15.47 % Ba
Aluminum 18.24 % Al
Hydrogen 1.36 % H 
Sulfur 14.45 % S 
Oxygen 50.47 % O 
 Empirical Formula:
Ba0.5Al3(SO4)2(OH)6
 IMA Status:
Approved IMA
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
white or yellowish.
 Diaphaniety:
Transparent
 Hardness:
3-4 - Calcite-Fluorite
 Luster:
Vitreous (Glassy)
 Streak:
white
More details...