Hematite (beautiful kidney-shaped crystallizations) from Tawsli, Morocco.

Hematite, derived from the Greek 'haima' meaning blood, is a mineral composed mainly of iron(III) oxide, Fe2O3. It is known in varieties such as the red bloodstone and the gray-black to black iron luster and micaceous iron. With a hardness of 5 to 6, hematite is known for its distinctive blood-red streak color when rubbed over unglazed porcelain, which also explains its name. It may contain traces of magnesium, manganese and titanium. Hematite is both a corridor mineral and a sedimentary mineral and often causes the red coloring of rocks. It is often found together with other iron ores such as magnetite, limonite and iron spar. When magnetite transforms to hematite, it is called martite. Hematite occurs worldwide, with significant deposits in Europe, Africa and the United States, and more than half of the world's production comes from China, Brazil and Australia. It is also present in high concentrations on Mars, contributing to the planet's orange-red color. Pure hematite contains 70% iron, making it the most important iron ore. It is extracted by reaction with carbon at high temperature and is also used as a polishing agent and mirror due to its high reflectance. The red color and non-toxicity make hematite very suitable for various applications.