Sabieite

Sabieite is a mineral with the chemical formula (NH4)Fe+++(SO4)2. It is found in South Africa. Its crystals are trigonal to trapezohedral. It is white and leaves a white streak. It is transparent and has an earthy luster. Sabieite is rated 2 on the Mohs Scale.
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General Information:
 Chemical Formula:
(NH4)Fe+++(SO4)2
 Composition:
(Molecular Weight = 266.01 gm)
Iron 20.99 % Fe
Hydrogen 1.52 % H 
Sulfur 24.11 % S 
Nitrogen 5.27 % N 
Oxygen 48.12 % O 
 Empirical Formula:
NH4Fe3+(SO4)2
 IMA Status:
Approved IMA
Physical Properties:
 Color:
white.
 Density:
2.68 - 2.69, Average = 2.68
 Diaphaniety:
Transparent
 Hardness:
2 - Gypsum
 Luster:
Earthy (Dull)
 Streak:
white
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