Ferrimolybdite

General Information:
 Chemical Formula:
Fe+++2(MoO4)3·8(H2O)
 Composition:
(Molecular Weight = 717.61 gm)
Iron 15.56 % Fe
Molybdenum 40.11 % Mo
Hydrogen 1.97 % H 
Oxygen 42.36 % O 
 Empirical Formula:
Fe3+2(MoO4)3·7(H2O)
 Environment:
Molybdenite mines.
 Locality:
Siberia, Russia.
 Name Origin:
Named from its chemical composition.
Physical Properties:
 Cleavage:
[001] Distinct
 Color:
yellow, canary yellow, or sulfur yellow.
 Density:
4 - 4.5, Average = 4.25
 Habits:
Earthy - Dull, clay-like texture with no visible crystalline affinities, (e.g. howlite)., Scaly - Morphology like fish scales., Fibrous - Crystals made up of fibers.
 Hardness:
2.5-3 - Finger Nail-Calcite
 Luster:
Silky
 Streak:
light yellow
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