Neotocite

General Information:
 Chemical Formula:
(Mn,Fe++)SiO3·(H2O) (?)
 Composition:
(Molecular Weight = 149.26 gm)
Manganese 27.60 % Mn
Iron 9.35 % Fe
Silicon 18.82 % Si
Hydrogen 1.35 % H 
Oxygen 42.88 % O 
 Empirical Formula:
Mn2+0.75Fe2+0.25SiO3·(H2O)
 Environment:
Secnodary mineral from the alteration of rhodonite and other manganese silicates.
Physical Properties:
 Cleavage:
None
 Color:
black, dark brown, or liver brown.
 Density:
2.8
 Diaphaniety:
Opaque
 Habits:
Colloform - Forming from a gel or colloidal mass., Amorphous - No crystalline form or imitative shape.,
 Hardness:
3-4 - Calcite-Fluorite
 Luster:
Resinous
 Streak:
brown
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