The physical and chemical indicators of crystalline compound salt should comply with the provisions of Table 1. Table 1 Physical and Chemical Indicators Item Indicators First-class and second-grade products Appearance of qualified products should be white, slightly yellow or bluish white crystal whiteness (R457), % ≥ 75 60 53 Table 1 Physical and chemical indicators (continued) Item indicators First-grade and second-grade products Grade qualified product sodium chloride-sodium sulfate, % ≥ 94.00 91.00 88.00 Moisture, % ≤ 5.00 6.00 7.00 Water-insoluble matter (calcium salt), % ≤ 0.40 2.00 3.00 Calcium and magnesium ions, % ≤ 0.60 1.00 2.00 Total leaching toxicity in the leachate The concentrations of hazardous components such as copper, total zinc, total cadmium, and total lead are lower than those specified in GB 5085.3.