Zinc Sulfate (also spelled zinc sulphate) is a very water soluble, clear, crystalline compound prepared by heating zinc sulphide ore in air and dissolving out and recrystallizing the sulphate. It is commonly used as the heptahydrate form; it occurs naturally as the mineral goslarite, and can be prepared by reacting zinc with sulfuric acid. The crystalline sulfate is known commonly as white vitriol. It loses water at 30 Celsius degree to give the hexahydrate and more water is lost at 70 Celsius degree to form the monohydrate. The anhydrous salt forms at 280 Celsius degree and this decomposes above 500 Celsius degree.  It is used in agriculture as a weed killer and to give protection against pests; It is used to supply zinc in animal feeds and fertilizers; It is also an important constituent of the precipitating bath in the manufacture of viscose rayon and in electrolyte for zinc plating; It functions as a mordant in dyeing; as a preservative for skins and leather; and as an astringent and emitic  in medicine.