mineral

Carnelian

SiO2 (Silicon Dioxide) with Iron Oxide impurities

AI-generated identification · may be incorrect

Hardness: 6.5-7 on Mohs scale; Color: reddish-orange, brownish-red; Luster: waxy to vitreous; Crystal structure: Trigonal (cryptocrystalline); Cleavage: none; Specific Gravity: 2.58-2.64

Hardness: 6
Color: reddish-orange, brownish-red
Luster: waxy to vitreous

Identified June 26, 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 (cryptocrystalline); Cleavage: none; Specific Gravity: 2.58-2.64

Formation & geological history

Formed in cavities and veins of volcanic rocks (igneous environments) when silica-rich waters precipitate at low temperatures; most often found in ancient riverbeds or coastal deposits.

Uses & applications

Used extensively in jewelry (beads, cabochons), carvings, and seals. Historically used for signet rings and amulets.

Geological facts

Ancient Egyptians called carnelian 'the setting sun' due to its color. It was believed to protect the wearer and is one of the oldest gemstones used by humans, dating back to Neolithic times.

Field identification & locations

Identified by its distinctive semi-translucent orange-red color and waxy appearance. Often found as water-worn pebbles in stream beds. Collectors should look for uniform saturation and lack of banding (unlike agate).