Ashanite

General Information:
 Chemical Formula:
(Nb,Ta,U,Fe,Mn)4O8
 Composition:
(Molecular Weight = 681.34 gm)
Uranium 27.95 % U 
Tantalum 26.56 % Ta
Manganese 1.61 % Mn
Niobium 21.82 % Nb
Iron 3.28 % Fe
Oxygen 18.79 % O 
 Empirical Formula:
4(Nb0.4)4(Ta0.25)4(U0.2)4(Fe2+0.1)4(Mn2+0.05)O8
 Environment:
Ashanite = a mixture of Ixiolite, Samarskite-(Y) and Uranmicrolite
 IMA Status:
Discredited IMA 1998
Physical Properties:
 Cleavage:
None
 Color:
dark brown or black.
 Density:
6.61
 Diaphaniety:
Opaque
 Hardness:
6-6.5 - Orthoclase-Pyrite
 Luster:
Sub Metallic
 Streak:
brown
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