Carnelian Agate

Physical Properties

Hardness: 6.5-7 on Mohs scale; Color: Orange, reddish-brown, semi-translucent; Luster: Vitreous to waxy; Crystal structure: Hexagonal (trigonal microcrystalline); Cleavage: None/Conchoidal fracture; Specific gravity: 2.58-2.64.

Formation & Geological History

Forms through the deposition of silica from groundwater into cavities of igneous rocks (volcanic lavas) or sedimentary rocks. The orange color is caused by iron oxide impurities. This process can occur over millions of years.

Uses & Applications

Widely used for gemstone carvings, beads for jewelry, cabochons, and as pocket stones or talismans in the spiritual crystal market.

Geological Facts

Carnelian was prized in ancient Egypt for amulets and rings, often associated with the solar disk and the goddess Isis. In ancient Rome, it was used for signet rings because hot wax does not stick to it.

Field Identification & Locations

Look for a translucent orange to brownish-red appearance with characteristic banded or waxy texture. It can be found in riverbeds or coastal areas where volcanic rock has weathered away. Common locations include Brazil, India, and Madagascar.

Identified on: 4/29/2026

Mode: Standard