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
More details...