Description: Magnesium sulfate heptahydrate 98% (agriculture grade) MgSO4 -7H2O CAS 7487-88-9 White small granular MgSO4 48.5% min Mg 9.8% min pH(5W/V%Sol) 5-8 Ferron(Fe) 0.002% max Heavy metal (Pb) 0.001 %max Size (mm) 0.1-1 0.2-3 1-4 Packing : 50kgs/bag.