Hematite (iron oxide) appears metallic silver-grey, black, or earthy red, but always leaves a reddish-brown to red streak. The streak, together with moderate hardness and no true cleavage, separates it from magnetite, ilmenite, and galena.
Field identification workflow
- Streak first, always: hematite leaves reddish-brown to red on porcelain no matter how silver, black, or earthy the specimen looks. The streak is the mineral's signature.
- Check the magnet: at most a weak pull. A strong cling means magnetite, whatever the color suggested.
- Heft it: iron oxides are noticeably heavy for their size.
- Botryoidal "kidney ore", glittering specularite, and rust-red earthy masses are all the same mineral — let the streak unify what the eye separates.