Ferricopiapite

General Information: Chemical Formula:Fe+++2/3Fe+++4(SO4)6(OH)2·20(H2O) Composition:(Molecular Weight = 1,231.32 gm)Iron 21.17 % FeHydrogen 3.44 % H Sulfur 15.63 % S Oxygen 59.77 % O  Empirical Formula: Fe3+0.6666Fe3+4(SO4)6(OH)2·20(H2O)Physical Properties: Cleavage:[???] Perfect Color:yellow or orange. Density:2.1 Diaphaniety:Transparent to Translucent Hardness:2.5-3 - Finger Nail-Calcite Luster:Pearly Streak:light yellowMore details...

Fe4.66(SO4)6(OH)2 20(H2O)