| Typical physical properties | |
|---|---|
| Hardness | ca. 7,5 – 8 mohs |
| Grain shape | angular |
| Melting point | ca. 1.300 °C |
| Specific gravity | ca. 3,5 – 4,3 g/cm3 |
| Bulk density* | ca. 1,9 – 2,2 g/cm3 |
*depending on grain size
| Typical chemical analysis | |
|---|---|
| SiO2 (no free silica) | 35,00 % |
| Fe2O3 | 33,00 % |
| Al2O3 | 23,00 % |
| MgO | 7,00 % |
| MnO | 1,00 % |
| CaO | 1,00 % |