Kazakhstanite

General Information:
 Chemical Formula:
Fe+++5V++++3V+++++12O39·8.5(H2O)
 Composition:
(Molecular Weight = 1,820.46 gm)
Vanadium 41.97 % V 
Iron 15.34 % Fe
Hydrogen 0.94 % H 
Oxygen 41.75 % O 
 Empirical Formula:
Fe3+5V4+3V5+12O39·8.5(H2O)
 Environment:
Black shales.
 IMA Status:
Approved IMA
 Locality:
Northwestern Karatau, Kazakhstan.
 Name Origin:
Named for the locality.
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
black.
 Density:
3.4 - 3.6, Average = 3.5
 Diaphaniety:
Opaque
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., ,
 Hardness:
2.5 - Finger Nail
 Luster:
Subadamantine
 Streak:
brownish black
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