Mohrite
Mohrite, (NH4)2Fe(SO4)2·6(H2O), is a rare sulfate mineral originally found in the geothermal fields of Tuscany, Italy. This Fe-dominant analogue of boussingaultite is sometimes reported from burning coal dumps.
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Wikipedia
Mohrite, (NH4)2Fe(SO4)2·6(H2O), is a rare sulfate mineral originally found in the geothermal fields of Tuscany, Italy. This Fe-dominant analogue of boussingaultite is sometimes reported from burning coal dumps.