mineral

Hematite (Ironstone) Nodule

Hematite (Fe2O3)

AI-generated identification · may be incorrect

Hardness: 5.5-6.5 Mohs scale. Color: Reddish-brown to metallic grey. Luster: Sub-metallic to dull/earthy. Crystal structure: Trigonal. Specific gravity: 5.26.

Hardness: 5
Color: Reddish-brown to metallic grey
Luster: Sub-metallic to dull/earthy

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 5.5-6.5 Mohs scale. Color: Reddish-brown to metallic grey. Luster: Sub-metallic to dull/earthy. Crystal structure: Trigonal. Specific gravity: 5.26.

Formation & geological history

Formed as a chemical precipitate in sedimentary environments or through the oxidation of iron-rich minerals. Common in Banded Iron Formations (BIFs) dating back over 2 billion years.

Uses & applications

Primary ore of iron for steel production. Pigments for paints and cosmetics. Polished for jewelry and decorative carvings.

Geological facts

The name hematite is derived from the Greek word for blood, 'haima', because of its red streak. It is also found in abundance on the surface of Mars, giving the planet its red color.

Field identification & locations

Identify by its heavy weight (high density) and by scratching it against unglazed porcelain; it should leave a distinct rust-red streak regardless of the specimen's external color.