mineral

Carnelian

Carnelian (SiO2 - Silicon Dioxide with Iron Oxide impurities)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale). Color: Ranges from pale orange to deep reddish-brown. Luster: Waxy to vitreous. Crystal structure: Trigonal/Hexagonal (microcrystalline). Cleavage: None (conchoidal fracture). Specific Gravity: 2.58–2.64.

Hardness: 6
Color: Ranges from pale orange to deep reddish-brown
Luster: Waxy to vitreous

Identified March 28, 2026More mineral →

Explore Carnelian in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed as a cryptocrystalline variety of quartz (chalcedony). It typically develops via low-temperature silica deposition in volcanic cavities (vugs) or sedimentary environments. Iron oxide impurities provide the red-orange tint. Found in geological formations ranging from the Cenozoic to much older Paleozoic eras.

Uses & applications

Predominantly used as a gemstone in jewelry (cabochons, beads), decorative bowls, and lapidary art. Historically used for intaglios and cylinder seals because it does not stick to hot wax or clay.

Geological facts

Carnelian was highly prized by ancient Egyptians, who called it 'the setting sun' and used it in amulets for protection. It was also widely used by ancient Romans and Greeks for signet rings. Its name is believed to derive from the Latin 'carnis' (flesh) or 'cornum' (cornel cherry).

Field identification & locations

Identify in the field by its distinct waxy luster, translucency, and inability to be scratched by a steel knife. It often occurs as smooth, rounded water-worn pebbles in stream beds. Common locations include Brazil, India, Uruguay, Madagascar, and the United States (Washington, Oregon).