Item Standard Appearance A white to off-white powder Specific rotation[α]20/D (C=1 in 6N HCl) -21±1 º（C=1,6N HCl） Heavy metal(Pb) Not more than 10ppm Melting Point 215~225℃ Loss on drying Not more than 0.50% Residue on ignition(sulfated) Not more than 0.20% Assay 98.0% to103.0%