| Item | Specifications |
| Assay | 98.5%~101.5% |
| Transmittance | ≥98 |
| Speciific rotation | -26.7°~-29.0° |
| Chloride | ≤0.02% |
| Sulfate | ≤0.02% |
| Heavy metals | ≤10PPM |
| Arsenic | ≤1PPM |
| Iron | ≤0.01% |
| Residue on ignition | ≤0.1% |
| Loss on drying | ≤0.2% |
| pH value | 5.0~6.5 |