Fermorite

General Information:
 Chemical Formula:
(Ca,Sr)5(AsO4,PO4)3(OH)
 Composition:
(Molecular Weight = 707.27 gm)
Strontium 24.78 % Sr
Calcium 17.00 % Ca
Arsenic 26.48 % As
Phosphorus 2.19 % P 
Hydrogen 0.14 % H 
Oxygen 29.41 % O 
 Empirical Formula:
Ca3Sr2(AsO4)2.5(PO4)0.5(OH)
Physical Properties:
 Cleavage:
None
 Color:
white or light pink.
 Density:
3.518
 Diaphaniety:
Translucent
 Hardness:
5 - Apatite
 Luster:
Greasy (Oily)
 Streak:
white
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