mineral

Carnelian Agate

Silicon Dioxide (SiO2) - Chalcedony containing Iron Oxide impurities

Hardness: 6.5-7 on Mohs scale; Color: Translucent orange to reddish-brown; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.64.

Hardness: 6
Color: Translucent orange to reddish-brown
Luster: Vitreous to waxy

Identified March 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the deposition of silica-rich groundwater in cavities of igneous volcanic stones. The orange hue is caused by the presence of iron oxide (hematite) during the formation process.

Uses & applications

Used primarily in jewelry as beads and cabochons, for ornamental carvings, and by collectors for metaphysical purposes. It has historical use in making wax seal stamps due to its non-stick surface.

Geological facts

Carnelian has been used for over 4,500 years; ancient Egyptians referred to it as the 'sunset stone' and believed it could help the soul travel to the afterlife. It was also widely used by the Romans and Greeks in signet rings.

Field identification & locations

Identify in the field by its translucent orange glow when held to the light and its smooth, shell-like (conchoidal) fracture pattern. Commonly found in Brazil, India, Uruguay, and Madagascar.

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