gemstone

Carnelian

Chalcedony (SiO2)

Hardness: 6.5-7 on the Mohs scale; Color: Red, reddish-orange, brown-orange; Luster: Vitreous to waxy; Crystal structure: Trigonal (microcrystalline quartz); Cleavage: None, exhibits conchoidal fracture; Specific gravity: 2.58-2.64

Hardness: 6
Color: Red, reddish-orange, brown-orange
Luster: Vitreous to waxy

Identified August 5, 2026More gemstone →

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Physical properties

Formation & geological history

Forms in low-temperature environments through the deposition of silica from groundwater in cavities of rocks, often volcanic or sedimentary, over millions of years.

Uses & applications

Widely used in jewelry, signet rings, beads, carvings, and as an ornamental stone since ancient times.

Geological facts

Carnelian was highly prized in ancient Egypt, where it was often placed in tombs to assist the passage of the dead into the afterlife, symbolizing the setting sun.

Field identification & locations

Can be identified by its distinctive reddish-orange translucent appearance, waxy luster, and conchoidal fracture. Commonly found in riverbeds, gravel deposits, and volcanic regions worldwide including India, Brazil, and the USA.