Quenstedtite

Quenstedtite is an uncommon iron sulfate mineral with formula Fe2(SO4)3.10H20. It forms violet or white crystals, and has been found at a couple of localities in Chile. It was named by G. Linck in 1888 after the German mineralogist F. A. von Quenstedt.
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General Information:
 Chemical Formula:
Fe+++2(SO4)3·10(H2O)
 Composition:
(Molecular Weight = 580.04 gm)
Iron 19.26 % Fe
Hydrogen 3.48 % H 
Sulfur 16.58 % S 
Oxygen 60.68 % O 
 Empirical Formula:
Fe3+2(SO4)3·10(H2O)
 Name Origin:
Named after the German mineralogist, F. A. Quenstedt (1809-1889).
Physical Properties:
 Cleavage:
[010] Perfect
 Color:
white, light violet, or red violet.
 Density:
2.14
 Diaphaniety:
Transparent
 Habits:
Euhedral Crystals - Occurs as well-formed crystals showing good external form., Granular - Generally occurs as anhedral to subhedral crystals in matrix.,
 Hardness:
2.5 - Finger Nail
 Luster:
Vitreous (Glassy)
 Streak:
light violet blue
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