gemstone

Tumbled carnelian (likely orange chalcedony)

Carnelian, a cryptocrystalline variety of quartz; SiO₂, commonly colored by iron oxides

AI-generated identification · may be incorrect

Mohs hardness 6.5–7; orange-red, translucent to opaque, with a waxy to vitreous luster and no visible cleavage. It has a microcrystalline quartz structure and typically shows smooth tumbled surfaces.

Identified August 9, 2026More gemstone →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities and fractures, with iron impurities producing the red-orange color; deposits commonly range from Cenozoic to older volcanic or sedimentary settings.

Uses & applications

Used for beads, cabochons, carvings, seals, and ornamental objects; attractive tumbled pieces are inexpensive jewelry and mineral-collecting specimens.

Geological facts

Carnelian is traditionally associated with vitality and has been used in ancient Egyptian, Roman, and Islamic jewelry. Stronger red-orange color and translucency generally increase desirability.

Field identification & locations

Common sources include India, Brazil, Uruguay, Madagascar, and Germany. Identify it by its orange-red color, quartz-like hardness, waxy luster, and inability to scratch with a steel knife easily; the image shows a polished/tumbled specimen.