Argentojarosite

General Information:
 Chemical Formula:
AgFe+++3(SO4)2(OH)6
 Composition:
(Molecular Weight = 569.58 gm)
Iron 29.41 % Fe
Silver 18.94 % Ag
Hydrogen 1.06 % H 
Sulfur 11.26 % S 
Oxygen 39.33 % O 
 Empirical Formula:
AgFe3+3(SO4)2(OH)6
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
brown, yellow, or yellow brown.
 Density:
3.66
 Diaphaniety:
Transparent to Translucent
 Habits:
Micaceous - Platy texture with "flexible" plates., ,
 Hardness:
3.5-4.5
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous (Glassy)
 Streak:
yellow
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