mineral

Carnelian

Carnelian (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 on Mohs scale; Color: Orange to reddish-brown; Luster: Vitreous to waxy; Crystal Structure: Hexagonal/Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

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

Identified May 9, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Orange to reddish-brown; Luster: Vitreous to waxy; Crystal Structure: Hexagonal/Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed at low temperatures in the oxidation zones of ore deposits or within volcanic rock cavities. Its color is derived from iron oxide impurities (hematite).

Uses & applications

Primarily used as a gemstone in jewelry, beads, and cabochons. Historically used for signet rings and wax seals because hot wax does not stick to it.

Geological facts

Carnelian was used by ancient Egyptians for amulets to aid the passage of spirits to the afterlife and was famously one of the twelve stones on the breastplate of Aaron.

Field identification & locations

Identify by its translucent, waxy orange-red appearance and conchoidal fracture. Often found as nodules in volcanic rocks or as water-worn pebbles in riverbeds.