| Assay: | 98.5-101.5% Fe(NH4)2(SO4)2 · 6H2O |
| MAXIMUM ALLOWABLE | |
| Insoluble matter: | 0.01% |
| Phosphate (PO4): | 0.003% |
| Calcium (Ca): | 0.005% |
| Copper (Cu): | 0.003% |
| Magnesium (Mg): | 0.002% |
| Manganese (Mn): | 0.01% |
| Potassium (K): | 0.002% |
| Sodium (Na): | 0.02% |
| Zinc (Zn): | 0.003% |
| Ferric ion (Fe3+): | 0.01% |