Hematite

The most important deposits are sedimentary. The largest production comes from the Lake Superior district in North America; other major deposits are in Minas Gerais, Brazil (in metamorphosed sediments), Cerro Bolívar in Venezuela, and Labrador and Quebec in Canada. Notable specimen and gem material comes from England (kidney ore from Cumberland), Brazil (near Ouro Preto), Elba in Italy, and many US states.

Whatever its appearance, natural hematite leaves a rust-red streak (blackish only in Ti-bearing varieties). Black crystals can be confused with ilmenite. The "hematite" used in jewelry, and often sold as magnetized items, is generally an artificially created material, not the mineral. Natural hematite is not magnetic; magnetic material sold as "hematine" or "magnetic hematite" contains no hematite, even though it can also leave a red streak. Hematite conducts electricity weakly, unlike the lookalike psilomelane.

Avoid mechanical cleaning such as steam or ultrasonic cleaners; use a soft brush, mild detergent and warm water. With a hardness of only 5–6 and a brittle tenacity, it scratches and chips more easily than harder gems.

The name was given around 300–325 BCE by Theophrastus, from the Greek "aematitis lithos" ("blood stone"), and Pliny the Elder rendered it as haematites ("bloodlike") in 79 CE, alluding to the vivid red colour of its powder. It is possibly the first mineral name ending in "-ite". Powdered hematite (red ochre) has been used as a pigment since the Stone Age, and rouge, a polishing compound, is powdered hematite. Ancient Egyptians made small tools such as a kohl pestle from it, and it has long been carved into cameos, intaglios, beads and cabochons.

Hematite is popularly associated with strength, resilience, protection and stability.

According to Bruce Knuth's Gems in Myth, Legend, and Lore, ancient warriors rubbed the moistened stone on their bodies in the belief that its "bloody residue" (the red streak) would protect them in battle, and ancient healers used it together with magical incantations. These are historical beliefs, not established effects.