mineral

Carnelian Agate

Silicon Dioxide (SiO2) - variety of Chalcedony

Hardness: 6.5-7 (Mohs scale), Color: Oranges and brownish-reds, Luster: Waxy to vitreous, Crystal structure: Trigonal/Microcrystalline, Cleavage: None/Conchoidal fracture, Specific gravity: 2.58-2.64

Hardness: 6

Identified June 9, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: Oranges and brownish-reds, Luster: Waxy to vitreous, Crystal structure: Trigonal/Microcrystalline, Cleavage: None/Conchoidal fracture, Specific gravity: 2.58-2.64

Formation & geological history

Formed in cavities of volcanic rocks or sedimentary rocks where silica-rich groundwaters deposit microcrystalline quartz over thousands to millions of years. Red colors come from iron oxide (hematite) impurities.

Uses & applications

Widely used in jewelry for cabochons, beads, and carvings. Also popular as a healing stone in metaphysical practices and as a decorative specimen for collectors.

Geological facts

Carnelian has been used for over 4,500 years; Ancient Egyptians called it 'the setting sun' and used it in amulets for the afterlife. It was also used for cylinder seals in Mesopotamia.

Field identification & locations

Identify in the field by its waxy luster, translucency, and conchoidal (shell-like) fractures. It is commonly found in Brazil, India, Uruguay, and Madagascar.

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