Black powder, soluble in acid, Insoluble in water and nitric acid ... : 86.94 Density: 5.026 g/cm3 Appearance: Black powder, soluble in acid, Insoluble in water and nitric acid, ... GradeZinc-Carbon GradeMnO291% min91% minMoisture1.2-2.0%1.2-2.0%D5035-40um20-25umD9088-105um55-60umFe90 ppm max90 ppm ... , magnetic materials, dye, medicine, ceramic, water treatment, etc. Electrolytic Manganese Dioxide