mineral

Carnelian

Silicon Dioxide (Quartz variety), SiO2

Hardness of 7 on the Mohs scale; orange to brownish-red color; vitreous to waxy luster; trigonal crystal system; conchoidal fracture with no cleavage; specific gravity of 2.60 to 2.65.

Identified August 3, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale; orange to brownish-red color; vitreous to waxy luster; trigonal crystal system; conchoidal fracture with no cleavage; specific gravity of 2.60 to 2.65.

Formation & geological history

Forms in low-temperature hydrothermal environments, volcanic cavities, and sedimentary rocks as silica-rich groundwater deposits microcrystalline quartz in cavities, often colored by iron oxide impurities.

Uses & applications

Used extensively in jewelry, as ornamental stone, for carved seals and signets since antiquity, and as a popular specimen for crystal healing and collecting.

Geological facts

Carnelian was prized in ancient civilizations like Ancient Egypt, where it was used in amulets and jewelry to ensure safe passage to the afterlife, and it is traditionally associated with courage and vitality.

Field identification & locations

Identified by its distinctive orange-to-red translucency and lack of cleavage; commonly found worldwide, particularly in Brazil, India, Uruguay, and the United States.