mineral

Carnelian

Chalcedony (SiO2) with Iron Oxide impurities

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Orange, reddish-orange, brownish-red; Luster: Vitreous to waxy; Crystal structure: Trigonal (microcrystalline); Cleavage: None; Specific gravity: 2.58–2.64.

Hardness: 6
Color: Orange, reddish-orange, brownish-red
Luster: Vitreous to waxy

Identified April 6, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Orange, reddish-orange, brownish-red; Luster: Vitreous to waxy; Crystal structure: Trigonal (microcrystalline); Cleavage: None; Specific gravity: 2.58–2.64.

Formation & geological history

Formed through the deposition of silica from groundwater into cavities of igneous rocks. The distinct reddish-orange color is caused by iron oxide (hematite) impurities present during formation.

Uses & applications

Predominantly used as a gemstone for jewelry (cabochons, beads, rings), decorative carvings, seals, and as a collector's mineral.

Geological facts

Carnelian has been used for over 4,500 years; ancient Egyptians referred to it as the 'Setting Sun' and used it in amulets. It was also widely used by Romans for signet rings because hot wax does not stick to it.

Field identification & locations

Identify by its waxy luster, translucency, and warm orange hue. It is often found in riverbeds or coastal areas as tumbled pebbles. Major sources include India, Brazil, Uruguay, and Madagascar.