gemstone

Red carnelian (red chalcedony)

Carnelian, a microcrystalline variety of quartz (SiO₂), commonly colored by iron oxides

AI-generated identification · may be incorrect

Mohs hardness 6.5–7; translucent orange-red to deep red, with a waxy to vitreous luster and no visible cleavage. It has cryptocrystalline quartz structure and typically conchoidal fracture; the specimen appears tumbled or naturally water-worn.

Identified August 19, 2026More gemstone →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater deposits chalcedony in cavities and fractures, with iron oxidation producing the red color. It commonly occurs in volcanic rocks and sedimentary gravels, generally from relatively young to ancient deposits.

Uses & applications

Used for beads, cabochons, carvings, seals, and ornamental objects; attractive polished pieces have modest jewelry value.

Geological facts

Carnelian is traditionally associated with vitality and protection and was widely used for ancient seals and signet rings.

Field identification & locations

Identify by its red-orange translucent body, waxy luster, hardness, and lack of cleavage; common sources include India, Brazil, Uruguay, Madagascar, and Namibia. The pictured piece may contain surface fractures or inclusions and could be dyed agate, so testing is advisable.