Alacranite

General Information:
 Chemical Formula:
As8S9
 Composition:
(Molecular Weight = 887.97 gm)
Arsenic 67.50 % As
Sulfur 32.50 % S 
 Empirical Formula:
As8S9
 IMA Status:
Approved IMA 1984
 Locality:
TL: Chile, Alacran, Pampa Larga
Physical Properties:
 Cleavage:
[???] Indistinct
 Color:
red or orange yellow.
 Density:
3.4 - 3.46, Average = 3.43
 Diaphaniety:
Transparent
 Hardness:
1.5 - Between Talc and Gypsum
 Luster:
Adamantine - Greasy
 Streak:
orange
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