| White crystalline powder | Complying |
| Assay (T) | 99-101%w/w |
| Calcium (Ca) | <= 0.005% |
| Chloride (Cl) | <= 0.003% |
| Heavy metals (as Pb) | <= 0.0005% |
| Iron (Fe) | <= 0.0005% |
| Sulfate (SO4) | <= 0.005% |
| Loss on drying (160°C) | 11-13% |
| pH (5% in water) | 7-9 |
| Insoluble matter | <= 0.005% |