| Technical specification | Special grade | Products First grade | Products Up to standard |
| L.O.I. (1000℃) ％ ≤ | 6.00 | 8.00 | 10.00 |
| Moisture％ ≤ | 0.2 | 0.4 | 0.7 |
| Acid unsolvable material ％ ≤ | 90.0 | 87.0 | 85.0 |
| Acid iron melted (taking Fe2O3) ％ ≤ | 0.20 | 0.40 | 0.50 |
| Material aspirated by magnet ％≤ | 0.04 | 0.07 | 0.10 |
| Passing through ％≥ | 45µm, 98 | 75µm, 98 | |