Molecular Formula: FeSO4 HS CODE:28332910 slightly green crystal for heptahydrate for heptahydrate and powder and granular for monohydrate ferrous sulphate Mainly used in water purification. Also used in feed additive and trace element fertilizer, also as raw material for production of lithopone and zinc salts, synthetic fiber industry, zinc plating, pesticides, or flotation. Fungicide etc.