Osarsite

General Information:
 Chemical Formula:
(Os,Ru)AsS
 Composition:
(Molecular Weight = 274.91 gm)
Arsenic 27.25 % As
Ruthenium 9.19 % Ru
Osmium 51.89 % Os
Sulfur 11.66 % S 
 Empirical Formula:
Os0.75Ru0.25AsS
 IMA Status:
Approved IMA 1972
 Locality:
Gold Bluff, 3 to 6 miles north of Orick, Humboldt Co., California.
 Name Origin:
Named after it's chemical composition of osmium and arsenic.
Physical Properties:
 Color:
gray.
 Density:
8.44
 Diaphaniety:
Opaque
 Hardness:
6 - Orthoclase
 Luster:
Metallic
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