Walpurgite

General Information:
 Chemical Formula:
Bi4(UO2)(AsO4)2O4·2(H2O)
 Composition:
(Molecular Weight = 1,753.84 gm)
Uranium 27.14 % U 
Bismuth 47.66 % Bi
Arsenic 8.54 % As
Hydrogen 0.23 % H 
Oxygen 16.42 % O 
 Empirical Formula:
Bi4UO22(AsO4)2O4·2(H2O)
Physical Properties:
 Cleavage:
[010] Perfect
 Color:
colorless, straw yellow, or wax yellow.
 Density:
5.95
 Diaphaniety:
Transparent to Translucent
 Hardness:
3.5 - Copper Penny
 Luster:
Adamantine - Greasy
 Streak:
yellow white
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