mineral

Carnelian (Agate)

Silicon Dioxide (SiO2)

Hardness: 6.5-7 on Mohs scale; Color: Orange, reddish-orange; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; SG: 2.58-2.64

Hardness: 6
Color: Orange, reddish-orange
Luster: Vitreous to waxy

Identified June 3, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Orange, reddish-orange; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; SG: 2.58-2.64

Formation & geological history

Formed in volcanic and sedimentary rocks as silica-rich groundwater percolates through cavities, depositing microcrystalline quartz; colored by iron oxide impurities.

Uses & applications

Primarily used in jewelry for beads, cabochons, and seals; also used in decorative carvings and lapidary art.

Geological facts

Carnelian has been used for over 4,500 years; ancient Egyptians referred to it as the 'Setting Sun' and used it in amulets for protection.

Field identification & locations

Identify by its translucent orange hue and waxy luster; often found in Brazil, India, and Uruguay; check for the absence of visible crystalline grains under magnification.