| Item | USP | CP |
| Identification | Conforms | |
| Particle Size(125mesh)(%) | -- | ≥85.0 |
| Sulfate (%) | ≤0.5 | |
| pH | 4.0-8.0 | 5.0-7.5 |
| Loss on drying (%) | ≤5.0 | |
| Assay(%) | ≥99.0 | |
| Chloride(%) | ≤0.1 | |
| Loss on Ignition (%) | ≤8.5 | |
| Arsenic (%) | ≤0.0003 | |
| Heavy metal (%) | -- | ≤0.003 |
| Iron(%) | -- | ≤0.015 |