mineral

Carnelian (Carnelian Agate)

Silicon dioxide (SiO2) - a variety of Chalcedony

Hardness: 6.5-7 on Mohs scale; Color: Reddish-orange, brownish-red; Luster: Waxy to vitreous; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Hardness: 6
Color: Reddish-orange, brownish-red
Luster: Waxy to vitreous

Identified April 29, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Reddish-orange, brownish-red; Luster: Waxy to vitreous; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed through the deposition of silica-rich groundwater in volcanic rock cavities or sedimentary environments. The red color comes from iron oxide (hematite) impurities.

Uses & applications

Commonly used in jewelry (beads, cabochons), carvings, decorative seals, and as a popular lucky stone or meditation aid in metaphysical circles.

Geological facts

Carnelian was highly prized in ancient times; ancient Romans used it for signet rings because hot wax does not stick to it. It has been used for thousands of years throughout Mesopotamia and Egypt.

Field identification & locations

Identify by its waxy luster, conchoidal fracture, and characteristic orange-red translucency. Commonly found in Brazil, India, Uruguay, and Madagascar.

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