... 98%ZnO 95%ZnO 90%Lead oxide (PbO)% ≤0.120.21.03.04.0Cadmium oxide (CdO) % ≤0.020.05------Cupric oxide ... , pigments, foods (source of Zn nutrient), batteries, ferrites, fire retardants, first aid tapes, etc. ZnO is present in the Earth's crust ...