Ilsemannite

General Information:
 Chemical Formula:
Mo3O8·n(H2O) (?)
 Composition:
(Molecular Weight = 433.83 gm)
Molybdenum 66.34 % Mo
Hydrogen 0.46 % H 
Oxygen 33.19 % O 
 Empirical Formula:
Mo3O8·(H2O)
Physical Properties:
 Cleavage:
[???] Good
 Color:
blue, blue black, or black.
 Hardness:
5.5-6 - Knife Blade-Orthoclase
 Streak:
brownish black
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