mineral

Carnelian

SiO2 (Silicon Dioxide - Chalcedony variant)

AI-generated identification · may be incorrect

Hardness 6.5-7 on Mohs scale, reddish-orange to brownish-red color, waxy to vitreous luster, trigonal microcrystalline structure, conchoidal fracture, no cleavage, specific gravity ~2.58-2.64.

Identified July 23, 2026More mineral →

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Physical properties

Hardness 6.5-7 on Mohs scale, reddish-orange to brownish-red color, waxy to vitreous luster, trigonal microcrystalline structure, conchoidal fracture, no cleavage, specific gravity ~2.58-2.64.

Formation & geological history

Forms in low-temperature hydrothermal environments and silica-rich solution deposits within volcanic rock cavities, basalt gas bubbles, and sedimentary deposits.

Uses & applications

Widely used for lapidary work, cabochons, carved gemstones, beads, tumbled pocket stones, and decorative jewelry.

Geological facts

Carnelian has been used for jewelry and seal rings for over 4,500 years. Ancient Romans used carnelian signet rings to seal wax documents because hot wax does not stick to it.

Field identification & locations

Identified by its warm translucent reddish-orange to brownish color, smooth waxy polish, and high hardness (scratches glass). Commonly found in Brazil, India, Madagascar, Uruguay, and parts of the USA.