mineral

Carnelian

Carnelian (Silicon Dioxide, SiO2)

Hardness: 6.5-7.0 (Mohs scale), Color: Orangered to brownish-red, Luster: Vitreous to waxy, Crystal Structure: Trigonal (cryptocrystalline), Cleavage: None, Specific Gravity: 2.58-2.64

Hardness: 6

Identified June 30, 2026More mineral →

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Physical properties

Hardness: 6.5-7.0 (Mohs scale), Color: Orangered to brownish-red, Luster: Vitreous to waxy, Crystal Structure: Trigonal (cryptocrystalline), Cleavage: None, Specific Gravity: 2.58-2.64

Formation & geological history

Formed in volcanic environments and sedimentary rocks by the precipitation of silica from groundwater; often found as nodules in ancient volcanic basalt or as pebbles in riverbeds.

Uses & applications

Primarily used in jewelry (cabochons, beads), decorative carvings, wax seals, and spiritual/metaphysical collections.

Geological facts

In ancient Egypt, Carnelian was called the 'setting sun' and was believed to protect the spirit in the afterlife. It was also widely used for signet rings and cylinder seals throughout the ancient Near East because hot wax does not stick to it.

Field identification & locations

Identify by its translucent brownish-red hue and lack of visible crystalline structure. Common locations include India, Brazil, Uruguay, and Madagascar. Collectors should look for uniform color and high translucency.