Hematite
Iron Oxide (Fe2O3) · Mineral Specimen / Industrial Mineral / Semi-Precious Gemstone
Crystal System
Trigonal. Commonly occurs in massive, botryoidal (kidney ore), micaceous (specularite), or tabular habits; the image shows a massive, slightly metallic-to-earthy habit.
Mineral Group
Oxides (Hematite group)
Chemical Formula
Fe2O3 (Iron(III) oxide), sometimes containing trace amounts of titanium, magnesium, or manganese.
Formation Process
Primarily Sedimentary (precipitation in seawater) or Igneous (magmatic segregation), but also occurs in hydrothermal veins and as a weathering product of other iron-bearing minerals.
About This Crystal
The specimen exhibits a dark grey to blackish metallic luster with distinct patches of reddish-brown earthy oxidation. The surface appears rugged, showing uneven fractures and a somewhat sub-metallic sheen characteristic of iron ore.
Physical Characteristics
Color varies from steel-grey to reddish-brown; streak is a diagnostic cherry-red; fracture is uneven to sub-conchoidal; specific gravity is high at ~5.26; non-magnetic (unlike magnetite), though can be weakly magnetic if impurities are present.
Optical Properties
Opaque; metallic to sub-metallic luster; extreme birefringence in thin sections, but generally observed as having a very high refractive index (2.94–3.22).
Hardness & Durability
Origin Region
Global distribution; notably Brazil (Minas Gerais), USA (Lake Superior), South Africa, and Morocco. Found in banded iron formations and weathering zones.
Hardness & Durability
Mohs hardness of 5.5 to 6.5; brittle tenacity; lacks cleavage. Relatively durable but can be scratched by quartz or steel.
Care & Maintenance
Avoid contact with harsh acids; clean with warm soapy water and a soft cloth; keep dry to prevent surface oxidation; store separately from softer minerals to avoid scratching them.
Rarity & Value
Common mineral; very abundant globally. Value for specimens is generally low unless they exhibit rare habits like 'Iron Roses' or specularite; primarily valued as the world's most important iron ore.
Special Characteristics
Known for its 'Red Streak' even when the stone appears black; can exhibit iridescence (Turgite); some varieties show a 'specular' (sparkling crystalline) effect.
Lore & History
Used as a pigment (red ochre) since the Stone Age for cave paintings; historically used in mourning jewelry in the Victorian era. In traditional lore, it is believed to be a 'grounding' stone associated with the Root Chakra and protection.