mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2) - variety of Chalcedony

AI-generated identification · may be incorrect

Hardness: 6.5-7 on Mohs scale; Color: Reddish-orange, amber, or brownish-red; Luster: Waxy to vitreous; Crystal structure: Trigonal (microcrystalline); Cleavage: None; Fracture: Conchoidal.

Hardness: 6
Color: Reddish-orange, amber, or brownish-red
Luster: Waxy to vitreous

Identified July 3, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Reddish-orange, amber, or brownish-red; Luster: Waxy to vitreous; Crystal structure: Trigonal (microcrystalline); Cleavage: None; Fracture: Conchoidal.

Formation & geological history

Formed as a result of silica-rich groundwater percolating through cavities in volcanic rocks. The orange-red color is caused by iron oxide impurities. It is found in igneous environments and often weathered into sedimentary deposits.

Uses & applications

Commonly used in jewelry (cabochons, beads, rings), decorative carvings, and as a popular lapidary material for hobbyists.

Geological facts

Carnelian was highly valued in ancient Egypt, where it was believed to assist the soul's journey into the afterlife. It was also widely used for signet rings and cylinder seals because hot wax does not stick to it.

Field identification & locations

Identify by its translucent waxy luster and shell-like (conchoidal) fractures. Found in riverbeds, gravel deposits, and volcanic field areas in Brazil, India, Madagascar, and the United States (especially the Pacific Northwest).