mineral

Carnelian

Carnelian Chalcedony (SiO2 with Iron Oxide impurities)

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

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

Identified February 20, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the deposition of silica-rich groundwater in cavities of igneous rocks such as basalt. The characteristic reddish hue comes from iron oxide (hematite) impurities. It can form in various geological ages depending on the host rock environment.

Uses & applications

Primarily used in jewelry (beads, cabochons), as an ornamental stone for carvings, seals, and historical lapidary work. It is also a popular specimen for crystal healing and mineral collecting.

Geological facts

Carnelian has been used as a gemstone since the Neolithic period; it was highly prized by the ancient Egyptians and Romans for signet rings and amulets because it does not stick to hot wax. Napoleon Bonaparte notably possessed a carnelian seal found during the Egyptian campaign.

Field identification & locations

Identify in the field by its translucent body, smooth waxy feel when tumbled, and vibrant orange-to-red color. It is commonly found in India, Brazil, Egypt, Uruguay, and Madagascar. Collectors look for uniform color and high translucency.

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