General Information:
Chemical Formula:
(Ag,Cu,Fe)12(Sb,As)4S13
Composition:
(Molecular Weight = 1,929.46 gm)
Iron 3.47 % Fe
Copper 11.86 % Cu
Silver 40.25 % Ag
Antimony 18.93 % Sb
Arsenic 3.88 % As
Sulfur 21.60 % S
Empirical Formula:
Ag7.2Cu3.6Fe2+1.2Sb3AsS13
Locality:
Freiberg district, Saxony.
Name Origin:
Named after its locality.
Physical Properties:
Cleavage:
None
Color:
gray, steel gray, or black.
Density:
4.85 - 5, Average = 4.92
Diaphaniety:
Opaque
Habits:
Massive - Granular - Common texture observed in granite and other igneous rock., ,
Hardness:
3.5-4 - Copper Penny-Flourite
Luster:
Metallic
Streak:
reddish black
More details...