mineral

Hematite Nodule / Concretion

Hematite (Fe2O3)

Hardness: 5.5 to 6.5 on the Mohs scale. Color: Brownish-red to reddish-brown (on the weathered outer surface) and metallic gray internally. Luster: Dull to earthy on the exterior, submetallic to metallic on fresh surfaces. Crystal Structure: Trigonal. Cleavage: None. Specific Gravity: 5.26.

Hardness: 5

Identified July 28, 2026More mineral →

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Physical properties

Formation & geological history

Formed by the precipitation of iron oxides from aqueous solutions, often as concretions or nodules in sedimentary environments, or through weathering and oxidation processes of iron-bearing rocks.

Uses & applications

Used as an ore of iron, in jewelry, carving ornamental objects, and as a polishing powder (rouge).

Geological facts

Hematite is the most important ore of iron. Its name is derived from the Greek word 'haima', meaning blood, due to the red color of its powder.

Field identification & locations

Identified by its distinctive reddish-brown streak, heavy weight relative to its size, and earthy exterior weathering common in iron-rich nodules. Found worldwide in sedimentary iron formations.