mineral

Carnelian Agate

Silicon Dioxide (SiO2) - variety of Chalcedony

Hardness: 6.5-7 on Mohs scale. Color: Translucent orange to reddish-brown. Luster: Waxy to vitreous. Crystal Structure: Trigonal (cryptocrystalline). Cleavage: None (conchoidal fracture). Specific Gravity: 2.58-2.64.

Hardness: 6
Color: Translucent orange to reddish-brown
Luster: Waxy to vitreous

Identified May 26, 2026More mineral →

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Physical properties

Formation & geological history

Formed in low-temperature silica-rich environments, typically in volcanic rocks, cavities (geodes), or sedimentary deposits where silica-rich fluids permeate through rock. The color is caused by iron oxide impurities.

Uses & applications

Primarily used in jewelry for cabochons and beads, ornamental carvings, and widely collected as tumbled stones or mineral specimens.

Geological facts

Carnelian has been used for over 4,500 years; Romans used it for signet rings because hot wax does not stick to it. It was also considered a stone of courage and high energy in ancient Egypt.

Field identification & locations

Identify by its translucent waxy appearance and orange-red hue. It is commonly found in India, Brazil, Uruguay, and various river beds worldwide where volcanic rock has weathered.

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Mineral/Rock

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Metamorphic Rock

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mineral