mineral

Carnelian Agate

Silicon Dioxide (SiO2) with Iron Oxide impurities

Hardness: 6.5-7 (Mohs); Color: Reddish-orange to brownish-red; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline (Cryptocrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.64

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

Identified April 14, 2026More mineral →

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Physical properties

Formation & geological history

Formed in low-temperature hydrothermal environments where silica-rich fluids deposit in volcanic rock cavities or sedimentary layers. The red color is derived from hematite (iron oxide) inclusions. Ages range from millions to hundreds of millions of years.

Uses & applications

Primarily used in jewelry (beads, cabochons), ornamental carvings, and as therapeutic 'healing stones' in metaphysical markets.

Geological facts

Carnelian was famously used by Ancient Egyptians for lapis-lazuli status and protective amulets. It was also widely used for signet rings in Ancient Rome because wax does not stick to it.

Field identification & locations

Identify by its translucent reddish-orange 'banding' (agate characteristic) and high hardness (it will scratch glass). Commonly found in Brazil, India, Uruguay, and Madagascar.

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