mineral

Carnelian

SiO2 (Silicon dioxide)

Hardness: 6.5-7 (Mohs scale), Color: Orange to reddish-orange, Luster: Vitreous to dull, Crystal structure: Hexagonal, Cleavage: None, Specific gravity: 2.59-2.61

Hardness: 6

Identified August 3, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: Orange to reddish-orange, Luster: Vitreous to dull, Crystal structure: Hexagonal, Cleavage: None, Specific gravity: 2.59-2.61

Formation & geological history

Forms in silica-rich environments, often as nodules or veins in volcanic or sedimentary rocks. The orange color is due to iron oxide impurities.

Uses & applications

Used primarily in jewelry, cabochons, carvings, and as a collector's specimen.

Geological facts

Carnelian has been used in jewelry and decorative items since antiquity, highly prized by ancient Egyptians, Greeks, and Romans.

Field identification & locations

Identified by its distinctive orange to reddish-orange color, waxy luster, and conchoidal fracture. Often found in India, Brazil, Uruguay, and Madagascar.