Ianthinite

General Information:
 Chemical Formula:
(UO2)·5(UO3)·10(H2O)
 Composition:
(Molecular Weight = 304.04 gm)
Uranium 78.29 % U 
Hydrogen 0.66 % H 
Oxygen 21.05 % O 
 Empirical Formula:
UO2(OH)2
 Environment:
Sedimentary uranium deposits.
 Locality:
Kasolo, Belgian Congo.
 Name Origin:
From the Greek ianthinos, "violet."
Physical Properties:
 Cleavage:
[100] Perfect
 Color:
violet black, violet, or violet purple.
 Density:
5.16
 Diaphaniety:
Transparent to translucent
 Habits:
Acicular - Occurs as needle-like crystals., Granular - Generally occurs as anhedral to subhedral crystals in matrix.,
 Hardness:
2.5-3 - Finger Nail-Calcite
 Luster:
Sub Metallic
 Streak:
violet brown
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