mineral

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

Hardness: 6.5-7 on Mohs scale; Color: semi-translucent reddish-orange to brownish-red; Luster: vitreous to waxy; Crystal structure: Trigonal (microcrystalline); Cleavage: none; Specific Gravity: 2.58-2.64

Hardness: 6
Color: semi-translucent reddish-orange to brownish-red
Luster: vitreous to waxy

Identified June 16, 2026More mineral →

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Physical properties

Formation & geological history

Formed in volcanic and sedimentary environments, often as fillings in cavities of lavas or through the deposition of silica from groundwater; can be found in various geological ages ranging from recent to millions of years old.

Uses & applications

Primarily used in jewelry (cabochons, beads), decorative carvings, and as a healing stone in lapidary arts. Historically used for signet rings and wax seals because hot wax does not stick to it.

Geological facts

Carnelian was widely used in ancient Rome and Egypt for amulets and seals. It gets its reddish color from iron oxide (hematite) impurities. It was one of the stones in the High Priest's Breastplate mentioned in the Bible.

Field identification & locations

Identified in the field by its translucency, waxy luster, and lack of visible crystals. Commonly found in Brazil, India, Uruguay, and Madagascar. Collectors should look for uniform color and high translucency.

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