Erionite-Na

General Information:
 Chemical Formula:
NaFeS2·2(H2O)
 Composition:
(Molecular Weight = 179.00 gm)
Sodium 12.84 % Na
Iron 31.20 % Fe
Hydrogen 2.25 % H 
Sulfur 35.83 % S 
Oxygen 17.88 % O 
 Empirical Formula:
NaFe2+S2·2(H2O)
 IMA Status:
Approved IMA 1977
 Locality:
Coyote Peak diatreme, 16 miles SW of Orick, Humboldt Co. California.
Physical Properties:
 Cleavage:
[110] Good
 Color:
copper red, red, or black.
 Density:
2.3
 Diaphaniety:
Opaque
 Hardness:
2 - Gypsum
 Luster:
Metallic
 Streak:
black
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