mineral

Carnelian Agate

Carnelian (Chalcedony / Silicon Dioxide SiO2)

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

Hardness: 6
Color: Reddish-orange to brownish-red
Luster: Vitreous to waxy

Identified June 2, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed as a secondary mineral in volcanic cavities or sedimentary environments by the deposition of silica from groundwater; its red color comes from iron oxide (hematite) impurities.

Uses & applications

Widely used in jewelry (beads, cabochons), carvings, metaphysical items, and lapidary arts. Historically used for signet rings and wax seals because hot wax does not stick to it.

Geological facts

Carnelian was highly prized in Ancient Egypt as a symbol of life and vitality, often buried with the dead to assist in the afterlife journey. It is also mentioned in the Old Testament as one of the stones in the High Priest's Breastplate.

Field identification & locations

Identify by its translucent reddish-orange color and lack of distinct crystal visible to the naked eye. Often found as rounded pebbles in riverbeds or beaches; common locations include India, Brazil, and Uruguay.

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