Orthowalpurgite

General Information:
 Chemical Formula:
(UO2)Bi4O4(AsO4)2·2(H2O)
 Composition:
(Molecular Weight = 1,483.82 gm)
Uranium 16.04 % U 
Bismuth 56.34 % Bi
Arsenic 10.10 % As
Hydrogen 0.27 % H 
Oxygen 17.25 % O 
 Empirical Formula:
(UO2)Bi4O4(AsO4)2·2(H2O)
 Environment:
May have formed by weathering of emplectite, wittichenite or other Bi-bearing ore minerals. Dimorphous with walpugite.
 IMA Status:
Approved IMA
 Locality:
The Schmiedestollen, Wittichen, Black Forest, Germany.
 Name Origin:
It is an orthorhombic polymorph of walpurgite.
Physical Properties:
 Cleavage:
[001] Indistinct
 Color:
pale yellow.
 Density:
6.5
 Diaphaniety:
Transparent
 Habits:
Tabular - Form dimensions are thin in one direction., Crystalline - Fine - Occurs as well-formed fine sized crystals.,
 Hardness:
4.5 - Between Fluorite and Apatite
 Luminescence:
Non-fluorescent.
 Luster:
Adamantine
 Streak:
pale yellow
More details...