mineral

Carnelian (polished)

Carnelian (variety of Chalcedony), SiO2

Hardness: 6.5-7 (Mohs); Color: Orange, reddish-brown; Luster: Vitreous to waxy; Crystal structure: Hexagonal (trigonal microcrystalline); Specific gravity: 2.58-2.64

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

Identified June 27, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Orange, reddish-brown; Luster: Vitreous to waxy; Crystal structure: Hexagonal (trigonal microcrystalline); Specific gravity: 2.58-2.64

Formation & geological history

Forms in low-temperature hydrothermal environments where silica-rich fluids fill cavities in volcanic or sedimentary rocks. It is most commonly found in volcanic geodes.

Uses & applications

Used primarily in lapidary work for jewelry, cabochons, beads, and carved figurines. Historically used for signet rings and amulets.

Geological facts

Carnelian was believed by ancient Egyptians to have protective properties. Its reddish color comes from iron oxide (hematite) impurities within the silica structure.

Field identification & locations

Identify by its translucent, waxy appearance and orange-red hue. It is commonly found in India, Brazil, Madagascar, and Uruguay. Collectors look for uniform color and high translucency.

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