mineral

Carnelian

Carnelian (Silicon Dioxide, SiO2)

Hardness: 6.5-7.0 (Mohs scale); Color: Orangey-red to brownish-red; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.64

Hardness: 6
Color: Orangey-red to brownish-red
Luster: Vitreous to waxy

Identified May 27, 2026More mineral →

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Physical properties

Formation & geological history

Formed in volcanic cavities or sedimentary environments as silica-rich water deposits cryptocrystalline quartz. The color is derived from iron oxide impurities.

Uses & applications

Primarily used for semi-precious jewelry, beads, seals, and lapidary art. Historically used for signet rings and amulets.

Geological facts

Carnelian was highly valued in ancient Egypt as the 'setting sun' and was believed to protect the wearer in the afterlife. It is the translucent variety of chalcedony.

Field identification & locations

Identify by its characteristic warm orange-red glow when backlit; it lacks the banding seen in Agate. Commonly found in India, Brazil, Madagascar, and Uruguay.