White crystal(99.5%) Size 1mm-4mm\0.2mm-3mm\0.1-1mm. (Agriculture grade): Main content 99.5% min MgSO4 48.59% min MgO 16.24% min Mg 9.8% min PH(5W/V%Sol) 5-9 Ferron(Fe) 0.002% max Chloride(CL) 0.02% Heavy metal (Pb) 0.001 %max Arsenic(As) 0.0002% max Insoluble 0.01%max. (Industry Grade): Main content 99.5% min MgSO4 48.59% min MgO 16.24% min Mg 9.8% min PH(5W/V%Sol) 5-9 Ferron(Fe) 0.0015% max Chloride(Cl) 0.015%max Heavy metal (Pb) 0.0008 %max Arsenic(As) 0.0002% max Insoluble 0.01%max. (Feed Grade): Main content 99.5% min MgSO4 48.59% min MgO 16.24% min Mg 9.8% min PH(5W/V%Sol) 5-9 Ferron(Fe) 0.001% max Chloride(Cl) 0.014%max Heavy metal (Pb) 0.0008%max Arsenic(As) 0.0002% max Insoluble 0.001%max. (Food Grade): Main content 99.5% min MgSO4 48.59% min MgO 16.24% min Mg 9.8% min PH(5W/V%Sol) 5-9 Ferron(Fe) 0.001% max Heavy metal(Pb) 0.0001%max Chloride(Cl) 0.01%max Arsenic(As) 0.0001% max Insoluble 0.001%max . 25kg(50kg) PP bag with PE inner.