mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2)

Hardness: 6.5-7.0 (Mohs); Color: Orange, reddish-brown to brownish-red; Luster: Waxy to vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.58-2.64

Hardness: 6
Color: Orange, reddish-brown to brownish-red
Luster: Waxy to vitreous

Identified May 24, 2026More mineral →

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Physical properties

Hardness: 6.5-7.0 (Mohs); Color: Orange, reddish-brown to brownish-red; Luster: Waxy to vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed through the deposition of silica from groundwater into cavities of igneous rocks, particularly volcanic lavas. The reddish hue comes from iron oxide (hematite) impurities.

Uses & applications

Primarily used as a gemstone in jewelry (beads, cabochons, rings), for carving seals and intaglios, and in lapidary arts.

Geological facts

In ancient times, carnelian was believed to calm anger and provide courage in battle. It was widely used in Ancient Egypt for amulets and scarabs, believed to assist the soul in its journey to the afterlife.

Field identification & locations

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