Our works is one of the biggest manufactures of zinc sulphate and indium ingots in China which has its own rights of Import & Export ,with annual output of 20000MT for zinc sulphate and 40 MT for indium .For you reference ,the following is our products'specifications.   Zinc Sulphate Heptahydrate:  Purity (ZnSO4.7H2O):98%min  zinc(Zn):22%min Pb:0.002%max Cd:0.002%max  Zinc Sulphate MoNo(Power/particulate):  Purity (ZnSO4.7H2O):98%min  zinc(Zn):35%min  Pb:0.002%max Cd:0.002%max If you have any interests in our products ,please inform us at your convenience.Your early reply will be appreciated!  wendy HUNAN ZHUZHOU SHIFENG REFINED INDIUM WORKS