| Contenuto | 99% min. |
| Materia insolubile in acqua | 0.05% max. |
| Ferro (Fe) | 12.6%-13.4% |
| Cloruro (Cl) | 0.05% max. |
| SO4 | 0.03% max. |
| PB | 0.001% max. |
| PH (10 g/l, soluzione 25ºC) | 4.2-5.5 |