mineral

Carnelian Agate

Silicon Dioxide (SiO2) with iron impurities

Hardness: 6.5-7 on Mohs scale; Color: Red-orange to brownish-red; Luster: Vitreous to waxy; Crystal Structure: Hexagonal/Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.59-2.61

Hardness: 6
Color: Red-orange to brownish-red
Luster: Vitreous to waxy

Identified June 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the deposition of silica in gas cavities (vesicles) within volcanic rocks. The distinct reddish color comes from iron oxide impurities. It can be found in sedimentary environments as secondary deposits.

Uses & applications

Predominantly used for jewelry (beads, cabochons, rings), ornamental carvings, and seals. Historically used for signet rings and decorative amulets.

Geological facts

Carnelian has been used for over 4,500 years; ancient Egyptians called it 'the setting sun' and used it in jewellery to symbolize life and vitality. It is often heated to enhance its red color.

Field identification & locations

Identify in the field by its translucency and characteristic banded or uniform orange-red hue. Commonly found in Brazil, India, Uruguay, Madagascar, and Germany.

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Mineral/Rock

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Metamorphic Rock

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mineral