Angelellite

General Information:
 Chemical Formula:
Fe+++4(AsO4)2O3
 Composition:
(Molecular Weight = 549.22 gm)
Iron 40.67 % Fe
Arsenic 27.28 % As
Oxygen 32.04 % O 
 Empirical Formula:
Fe3+4(AsO4)2O3
 IMA Status:
Approved IMA 1959
Physical Properties:
 Cleavage:
[???] Indistinct
 Color:
black brown.
 Density:
4.867
 Hardness:
5.5 - Knife Blade
 Luster:
Adamantine - Metallic
 Streak:
reddish brown
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