Ferosíra
| prvek | obsah | 
|---|---|
| S | 39-41 min. | 
| Fe | 51-54% max. | 
| C | 0,4-0,6 | 
| P | 0,02% max. | 
| O | 5-6% max. | 
| SiO2 | 0,8-1% max. | 
| Al2O3 | 3-8% max. | 
| Kusovost | 10-50 mm | 
| prvek | obsah | 
|---|---|
| S | 39-41 min. | 
| Fe | 51-54% max. | 
| C | 0,4-0,6 | 
| P | 0,02% max. | 
| O | 5-6% max. | 
| SiO2 | 0,8-1% max. | 
| Al2O3 | 3-8% max. | 
| Kusovost | 10-50 mm |