Synonyms: Zinc sulphide CAS: 1314-98-3 Molecular Formula: ZnS Molecular Weight: 97.46 g/mol Test Specification ZnS Content 98% min. Organic Treatment Present Brightness L* (powder) 97% min. Crystal Size (µm) Approx. 0.3 45 µm Sieve Residue 0.004% max. pH Approx. 7 Specific Gravity (g/cm3) Approx. 4.0 Specific Surface Area (m2/g) Approx. 8 Rel. Scattering Power (Reference pigment TiO2 = 100: PVC = 17%) Approx. 56 Hardness (Mohs) 3