Partheite

General Information:
 Chemical Formula:
Ca2Al4Si4O15(OH)2·4(H2O)
 Composition:
(Molecular Weight = 646.49 gm)
Calcium 12.40 % Ca
Aluminum 16.69 % Al
Silicon 17.38 % Si
Hydrogen 1.56 % H 
Oxygen 51.97 % O 
 Empirical Formula:
Ca2Al4Si4O15(OH)2·4(H2O)
 IMA Status:
Approved IMA 1979
Physical Properties:
 Cleavage:
[???] Good
 Color:
white.
 Density:
2.39
 Luster:
Vitreous (Glassy)
 Streak:
white
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