Natural Hematite — Rough

Hematite is an iron oxide with the chemical formula Fe₂O₃, being one of the most abundant iron minerals in the Earth's crust. It forms in a wide variety of geological environments: in banded iron (BIF) sedimentary deposits, in zones of supergeneous alteration of ferrous minerals, in hydrothermal veins, and as an accessory mineral in igneous and metamorphic rocks. Its color varies from metallic gray to black in massive and crystalline specimens, and red to brownish-red in earthy and powdery forms — a diagnostic characteristic of the species, where the trait always appears red regardless of the external color of the specimen. The characteristic metallic luster of crystalline specimens results from the high density and compact arrangement of iron and oxygen ions in the crystalline structure. Hardness: 5.5 to 6.5 on the Mohs scale. Density: 4.9 to 5.3 g/cm³. Crystalline system: trigonal. Available variations, approximate data: 1 to 3 cm — Approx. 0.010 kg — 250 pcs per kg 3 to 6 cm — 0.030 to 0.150 kg — 30 pieces per kg 6 to 15 cm — 0.150 to 0.800 kg — 2 to 3 pieces per kg