gemstone

Carnelian

Silicon Dioxide (Chalcedony variety), SiO2

Hardness of 6.5 to 7 on the Mohs scale, color ranges from orange-brown to deep reddish-orange, vitreous to waxy luster, microcrystalline (cryptocrystalline) quartz structure, conchoidal fracture, specific gravity of 2.58 to 2.64

Identified July 29, 2026More gemstone →

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Physical properties

Formation & geological history

Formed in low-temperature hydrothermal environments, volcanic cavities, and sedimentary rock infillings where silica-rich groundwater precipitates over millions of years

Uses & applications

Widely used in jewelry making for rings, necklaces, and beads, as well as carved into signet rings and intaglios throughout history

Geological facts

Carnelian was highly prized in ancient civilizations including Ancient Egypt, where it was associated with the goddess Isis and used in amulets to ensure safe passage to the afterlife

Field identification & locations

Identified by its distinctive brownish-orange color and waxy luster; commonly found in Brazil, India, Madagascar, and the United States

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