Arseniosiderite

General Information:
 Chemical Formula:
Ca2Fe+++3(AsO4)3O2·3(H2O)
 Composition:
(Molecular Weight = 766.50 gm)
Calcium 10.46 % Ca
Iron 21.86 % Fe
Arsenic 29.32 % As
Hydrogen 0.79 % H 
Oxygen 37.57 % O 
 Empirical Formula:
Ca2Fe3+3(AsO4)3O3·3(H2O)
Physical Properties:
 Cleavage:
[100] Good
 Color:
bronze brown, yellow, yellow brown, dark brown, or black.
 Density:
3.5 - 3.9, Average = 3.7
 Diaphaniety:
Translucent to Opaque
 Habits:
Fibrous - Crystals made up of fibers., ,
 Hardness:
1.5 - Between Talc and Gypsum
 Luminescence:
Non-fluorescent.
 Luster:
Sub Metallic
 Streak:
ochraceous
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