gemstone

Carnelian

Quartz (Variety: Chalcedony, SiO2)

Hardness of 7 on the Mohs scale; color ranges from orange-pink to deep reddish-brown; vitreous to waxy luster; trigonal crystal system with microcrystalline structure; conchoidal fracture with no true cleavage; specific gravity of 2.58-2.64.

Identified August 1, 2026More gemstone →

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Physical properties

Formation & geological history

Forms in low-temperature hydrothermal environments, groundwater solutions, and volcanic cavities where silica-rich solutions deposit microscopic quartz crystals colored by iron oxide impurities. Can be millions of years old.

Uses & applications

Widely used in jewelry, cabochons, beads, and carved into signet rings or talismans due to its long history as an ornamental gemstone.

Geological facts

Carnelian has been prized since ancient times, utilized extensively in Ancient Egypt as a stone of protection and life, and frequently found in Minoan and Roman archaeological sites.

Field identification & locations

Identified by its distinctive brownish-orange to red translucent color, waxy luster, and quartz hardness. Commonly sourced from India, Brazil, Uruguay, and the United States.