mineral

Carnelian

Carnelian (Chalcedony - SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 on the Mohs scale, Color: brownish-red to orange, Luster: vitreous, wax-like, Crystal structure: trigonal (microcrystalline), Cleavage: none, Specific gravity: 2.59-2.61

Hardness: 6

Identified September 24, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on the Mohs scale, Color: brownish-red to orange, Luster: vitreous, wax-like, Crystal structure: trigonal (microcrystalline), Cleavage: none, Specific gravity: 2.59-2.61

Formation & geological history

Formed as secondary deposits in cavities and fractures of igneous rocks, particularly basalts. The color is derived from iron oxide impurities.

Uses & applications

Commonly used in jewelry, cabochons, beads, and carvings. Historically used for signet rings and cameos.

Geological facts

Carnelian has been used in jewelry for thousands of years, dating back to the Early Neolithic. It was widely used during Roman times to make engraved gems for signet or seal rings for imprinting a seal with wax on correspondence.

Field identification & locations

Can be identified by its distinctive red-orange color, waxy luster, and conchoidal fracture. Often found in Brazil, India, Siberia, and Germany. Collectors look for pieces with uniform color and good translucency.