Arsenobismite

General Information:
 Chemical Formula:
Bi2(AsO4)(OH)3
 Composition:
(Molecular Weight = 607.90 gm)
Bismuth 68.75 % Bi
Arsenic 12.32 % As
Hydrogen 0.50 % H 
Oxygen 18.42 % O 
 Empirical Formula:
Bi2(AsO4)(OH)3
 Environment:
Oxidized ore at the 200 m level. An inadequately described species no discredited as being a preisingerite-rich concentrate with atelestite and beudantite.
 IMA Status:
Discredited IMA 1999
 Locality:
Mamoth mine, Tintic District, Utah, USA.
 Name Origin:
Named for it's composition.
Physical Properties:
 Color:
green, yellowish green, or brownish green.
 Density:
5.7
 Habits:
Cryptocrystalline - Occurs as crystals too small to distinguish with the naked eye., Pulverulent - Forms a loose, poorly-coherent powdery mass., Friable - Loosley cohesive material th at granulates with your fingers.
 Hardness:
3 - Calcite
 Luminescence:
Non-fluorescent.
 Streak:
greenish yellow
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