Zinc sulfate is the most important zinc salt, as a colorless prismatic crystal or white powder, its heptahydrate commonly known as alum Hao, is a naturally occurring mineral. Industrial applications It is the main raw material for manufacturing lithopone and zinc salts, also used as mordant dyeing, leather and wood preservative, but also the production of viscose fiber important auxiliary materials and vinylon fibers. Further, in the electrolytic plating industry and also has applications, it can also be used to manufacture cable. The water industry is the largest amount of cooling water. Cooling water in a closed-cycle cooling system can not have metal corrosion and scaling, so to be treated, a process called water quality stable, zinc sulfate is used here as water quality stabilizer. Pharmaceutical use Medicine for the emetic. Agricultural use Fruit tree nursery can be used to prevent disease, but also a trace element zinc supplement commonly used fertilizer crop fertilizer, do basic fertilizer, foliar fertilizer.