mineral

Carnelian Agate

Silicon dioxide (SiO2) - Chalcedony variety

Hardness: 6.5-7 (Mohs scale); Color: Orange, reddish-brown, semi-translucent with banding; Luster: Waxy to vitreous; Crystal structure: Hexagonal (trigonal) cryptocrystalline; Cleavage: None; Specific gravity: 2.58-2.64

Hardness: 6
Color: Orange, reddish-brown, semi-translucent with banding
Luster: Waxy to vitreous

Identified May 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the deposition of silica from groundwater in the cavities of igneous rocks, particularly volcanic lavas. The reddish-orange tint is caused by iron oxide impurities.

Uses & applications

Primarily used in jewelry (beads, cabochons), ornamental carvings, and as a semi-precious collector gemstone or healing stone.

Geological facts

In ancient Egypt, Carnelian was often placed on mummies to assist in the soul's journey into the afterlife. It is one of the oldest gemstones used for seals and signet rings.

Field identification & locations

Identify by its waxy luster, translucency, and warm orange-red color. It is common in river gravels and volcanic regions. Look for conchoidal fractures when broken.

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