Zinc Sulfate Heptahydrate White powder Used as raw material,for fiber,feed additive water treatment,etc. Zinc Sulfate HeptahydrateAppearance: White powder. ... for production of lithopone.It is also used in synthetic fiber industry, zinc plating, pesticides, mordant agent of printing and ... agent.It is mainly used in trace element fertilizer and feed additive, etc.If you are interested in zinc sulphate ...