gemstone

Carnelian

Silicon Dioxide (Variety of Chalcedony, SiO2)

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

Identified August 2, 2026More gemstone →

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Physical properties

Formation & geological history

Formed in low-temperature hydrothermal environments, volcanic cavities, and sedimentary rock formations through the deposition of silica-rich groundwater over millions of years.

Uses & applications

Widely used in jewelry such as rings, necklaces, and beads, as well as historically used for carved intaglios, signet rings, and talismans.

Geological facts

Carnelian has been prized since ancient times, frequently used in ancient Rome, Greece, and Egypt for royal signet rings and amulets due to the belief that it promoted courage and vitality.

Field identification & locations

Easily identified by its translucent orange-to-red hue and waxy luster. Common sources include India, Brazil, Uruguay, and Madagascar.

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