| Chemical Formula: | Fe2+Fe3+2O4 (Iron Oxide) |
| Class/Group: | Oxides and Hydroxides: Spinel |
| Appearance: | Black color, black streaks, opaque, metallic |
| Characteristics: | Strongly attracted to magnetic fields. |
| Hardness: | 5.5 - 6.5 |
| Specific Gravity: | 4.9 - 5.2 (typical of metallic minerals) |
| Crystal Forms: | Typically octahedrons, occasionally dodecahedrons or rhombododecahedron, very rarely cubic, sometimes a combination of. Typically striated, larger crystals can contain layer growths. Sometimes occurs in vains or rounded crystals. No cleavage, but parting sometime visible on octahedrons. Fracture is subconchoidal to uneven. |
| Often Found With: | Apatite, Calcite, Chlorite, Garnet, Hematite, Ilmenite, Phlogopite, Pyrite, Talc |
| Varieties: | lodestone (large and magnetic), titano (titanium rich), chrome (chromium rich) |