mineral

Carnelian

SiO2 (Silicon Dioxide) - Translucent Chalcedony

Hardness: 6.5-7.0 (Mohs); Color: Orange to reddish-brown; Luster: Waxy to vitreous; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.58–2.64

Hardness: 6
Color: Orange to reddish-brown
Luster: Waxy to vitreous

Identified February 22, 2026More mineral →

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Physical properties

Hardness: 6.5-7.0 (Mohs); Color: Orange to reddish-brown; Luster: Waxy to vitreous; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.58–2.64

Formation & geological history

Secondary formation in volcanic and sedimentary rocks where silica-rich fluids permeate cavities; the reddish color comes from iron oxide (hematite) impurities. It can be found in ancient geologically stable regions like the Deccan Traps.

Uses & applications

Extensively used in jewelry (beads, cabochons, carved intaglios), ornamental carvings, and historical seal stones.

Geological facts

Carnelian was prized by Ancient Egyptians for its solar symbolism and used in the pectoral of Tutankhamun. It was also widely used for signet rings throughout the Roman Empire because hot wax does not stick to it.

Field identification & locations

Identify in the field by its translucency, waxy surface, and characteristic orange-red hue. It is often found in river beds or desert environments in Brazil, India, Uruguay, and Madagascar.

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