Quality standard

Item Standard
food grade    
Identification in accordance with standard    
Assay ,%  98.0 - 102.0
Loss on dry %  0.30max
Reduzate %  0.50max
PH 6.2 -7.8
Sulfate %  0.05 max
Chloride %  0.07max
Pb u g/g  1max  
Arsenic salt  u g/g  2 max
Heavy metals u g/g 10max
Appearance of solution (1.0g,10ml water)  colorless, almost clear