gemstone

Carnelian

Silicon Dioxide (Chalcedony variety), SiO2

Hardness of 6.5 to 7 on the Mohs scale, red to reddish-orange color due to iron oxide impurities, waxy to vitreous luster, cryptocrystalline crystal structure, conchoidal fracture with no true cleavage, and a specific gravity of approximately 2.58 to 2.64.

Identified July 30, 2026More gemstone →

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Physical properties

Formation & geological history

Formed in low-temperature hydrothermal environments, volcanic cavities, and sedimentary deposits through the deposition of silica from groundwater rich in iron oxide.

Uses & applications

Used extensively in jewelry (beads, cabochons, rings), ornamental carvings, talismans, and prized as a historical gemstone.

Geological facts

Carnelian has been used since ancient times (dating back to the Neolithic period and ancient Egypt) for seals and signet rings. It is often associated with courage and vitality in historical lore.

Field identification & locations

Easily identified by its translucent red-to-orange coloration and waxy luster. It is commonly found in India (including the Deccan Traps region which aligns with the regional coordinates), Brazil, Uruguay, and Madagascar.

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