APPearance White or off-white crystalline powderSpecific Rotation(C=2,5NHCL) -26.0°~ -29.0Chloride (Cl) not more than 0.02%Loss on drying ≤0.5%Residue on Ignition not more than 0.2% Heavy Metals(Pb) not more than 10ppmAssay 98.5 to 100.5%