mineral

Carnelian

Chalcedony (Silicon Dioxide / SiO2)

Hardness: 6.5-7 on Mohs scale; Color: Translucent reddish-orange to brownish-red; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific Gravity: 2.58-2.64

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

Identified March 8, 2026More mineral →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Translucent reddish-orange to brownish-red; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific Gravity: 2.58-2.64

Formation & geological history

Formed through the deposition of silica from groundwater into cavities of igneous rocks such as basalt or volcanic rhyolite. Its color comes from iron oxide (hematite) impurities. It can be found in formations dating back millions of years.

Uses & applications

Primarily used in jewelry (cabochons, beads), decorative carvings, intaglios, and wax seals. It has significant value for gemstone collectors and practitioners of lithotherapy.

Geological facts

In ancient times, carnelian was used by Romans to create signet rings for sealing documents because hot wax does not stick to it. It was also buried with Egyptian pharaohs as a protective stone for the afterlife.

Field identification & locations

Identify in the field by its distinctive orange-red translucency and lack of visible crystal grains. It is commonly found in India, Brazil, Uruguay, and Madagascar. Collectors should look for even color distribution and high translucency.