Rambergite

Rambergite is a manganese sulfide mineral with formula MnS. It has been found in anoxic marine sediments, rich in organic matter and also in skarn in Sweden. It was named after the mineralogist, Hans Ramberg.It is closely related to Hauerite.
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General Information:
 Chemical Formula:
MnS
 Composition:
(Molecular Weight = 87.00 gm)
Manganese 63.14 % Mn
Sulfur 36.86 % S 
 Empirical Formula:
Mn2+S
 Environment:
Found in anoxic laminated sediments rich in organic matter. Dimorphic relationship with alabandite.
 IMA Status:
Approved IMA 1995 (Dana # Added)
 Locality:
Gotland Deep, Baltic Sea, off the coast of Sweden. Also found in a skarn in the Garpenberg area, Dalarna, Sweden.
 Name Origin:
Named after Hans Ramberg (1917-1998), Professor of Mineralogy and Petrology at the University of Chicago, then at the University of Uppsala, Sweden.
Physical Properties:
 Color:
brown or black.
 Diaphaniety:
Opaque
 Hardness:
4 - Fluorite
 Luster:
Resinous
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