mineral

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 on Mohs scale; Color: Orange, red, brownish-red; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64.

Hardness: 6
Color: Orange, red, brownish-red
Luster: Vitreous to waxy

Identified July 10, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Orange, red, brownish-red; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64.

Formation & geological history

Formed in cavities and veins of volcanic rocks (basalt/rhyolite) through the deposition of silica from groundwater; its red-orange tint comes from iron oxide impurities.

Uses & applications

Commonly used in jewelry (beads, cabochons), carvings, and seal stones; also highly valued by collectors as a pocket stone or tumbled specimen.

Geological facts

Carnelian was used widely in ancient Rome and Greece for signet rings because hot wax does not stick to it. It was also believed by ancient Egyptians to provide protection for the soul.

Field identification & locations

Identify by its translucent reddish-orange hue and waxy luster when polished. It lacks the distinct banding of agate but belongs to the same chalcedony family. Found globally in India, Brazil, and Uruguay.