Purity : min % 99.6 98.8 98.0 NaCl : max % 0.70 0.90 1.20 Fe : max % 0.0035 0.006 0.010 SO4 : max % 0.03 0.03 0.03 Insoluble matter in water: % 0.03 0.10 0.15 Loss on ignition : max %0.8 1.0 1.3 bulk density : min £¨g/ml£© 0.90 0.90 0.90 grain size : 180¦Ìm screenings min % 70.0 65.0 60.0 25kgs/bag, 40kgs/bag, 50kgs/bag.