Erlianite

General Information:
 Chemical Formula:
(Fe++,Mg)4(Fe+++,V+++)2[Si6O15](O,OH)8
 Composition:
(Molecular Weight = 861.42 gm)
Magnesium 1.41 % Mg
Vanadium 2.96 % V 
Iron 32.42 % Fe
Silicon 19.56 % Si
Hydrogen 0.94 % H 
Oxygen 42.72 % O 
 Empirical Formula:
Fe2+3.5Mg0.5Fe3+1.5V3+0.5Si6O15OH8
 IMA Status:
Approved IMA 1985
 Locality:
Harhada iron deposit, near the Jining-Erlian railway, Inner Mongolia, China.
 Name Origin:
Named for the locality.
Physical Properties:
 Cleavage:
[001] Perfect, [100] Perfect
 Color:
black.
 Density:
3.11
 Diaphaniety:
Nearly opaque
 Habits:
Fibrous - Crystals made up of fibers., Platy - Sheet forms (e.g. micas)., Aggregates - Made of numerous individual crystals or clusters.
 Hardness:
3.5 - Copper Penny
 Luster:
Silky
 Streak:
brown
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