Sr.No Characteristic Requirement for Grade i Grade ii 1 Sodium chloride (as nacl)percent by mass, min. 99.5 98.5 2 Matter insoluble in water percent by mass, max. 0.05 0.2 3 Calcium salts (as ca)percent by mass, max. 0.03 0.2 4 Magnesium salts (as mg) percent by mass, max. 0.01 0.10 5 Sulphate (as so4)percent by mass, max. 0.2 0.6 6 Iron compound (as fe) ppm max. 10.0 20.0 The moisture content shall not be more than 1% by mass for grade 1 & 4% by mass for grade Food grade specification : Appearance (color) white Appearance (form) powder Titration with agno3 99.0 - 101.5 % Insoluble matter