Appearance white crystals or crystalline powder State of solution Not less than 95% Specific Rotation -14.5º- -15.5º Assay 98.5%-101.0% Loss on drying ≤0.25% Residue on Ignition ≤0.10% Heavy Metals(Pb) ≤10ppm PH 5.2-6.2 Arsenic ≤10ppm Ammonium(NH4) ≤0.02%