Pig iron is ideally suitable for specialized applications such as pressure tight precision castings, automobile engine blocks, crankshafts, gears, rolling mill rolls, motor and generator housings, railway and machine tools.
| Silicon | Manganese | Sulphur | Phosphorous | Carbon |
| 1.5-1.99 | 0.50 | <0.06 | 0.12 | 4.0-4.5 |
| 2.0-2.49 | 0.50 | <0.06 | 0.12 | 4.0-4.5 |
| 2.5-3.0 | 0.50 | <0.06 | 0.12 | 4.0-4.5 |
| >3.0 | 0.50 | <0.06 | 0.12 | 4.0-4.5 |
| 0.80-1.49 | 0.50 | <0.06 | 0.12 | 4.0-4.5 |