mineral

Carnelian

Silicon Dioxide (Chalcedony variety), SiO2

Hardness of 6.5 to 7 on the Mohs scale, colors range from orange to reddish-brown and pinkish-orange, vitreous to waxy luster, microcrystalline (cryptocrystalline) crystal structure, conchoidal fracture with no cleavage, specific gravity of 2.58 to 2.64.

Identified August 3, 2026More mineral →

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Physical properties

Formation & geological history

Formed in low-temperature environments such as cavities within volcanic rocks or sedimentary rocks through the deposition of silica from groundwater rich in iron oxide impurities, which give it its characteristic red-orange color.

Uses & applications

Widely used in jewelry making for beads, cabochons, rings, and talismans, as well as in ornamental carvings and historical signet rings.

Geological facts

Carnelian has been prized since ancient times, frequently used in ancient Rome for wax seal rings because hot wax does not stick to it, and discovered in abundance in royal tombs like that of King Tutankhamun.

Field identification & locations

Identified by its waxy luster, translucent to semi-translucent appearance, distinct red-orange to brownish-red coloration, and lack of cleavage with conchoidal breakage. Commonly found in Brazil, India, Siberia, and the United States.

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Schist

Metamorphic

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

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