gemstone

Tumbled carnelian

Carnelian, orange-red chalcedony (microcrystalline quartz, SiO₂)

AI-generated identification · may be incorrect

Polished orange-red, translucent-to-opaque stone with a waxy/glassy luster and no visible cleavage; hardness 6.5–7 Mohs, trigonal quartz structure, specific gravity about 2.6. The photo is consistent with carnelian, though appearance alone cannot confirm identity.

Identified September 29, 2026More gemstone →

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Physical properties

Formation & geological history

Silica-rich fluids deposit chalcedony in cavities and veins, with iron compounds producing the orange-red color; commonly associated with volcanic rocks and sedimentary deposits. Formation ages vary widely.

Uses & applications

Used for beads, cabochons, ornaments, and carvings; historically valued for seals and jewelry.

Geological facts

Carnelian is a variety of chalcedony; its color may be enhanced by heating, a traditional treatment.

Field identification & locations

Look for uniform orange-to-red color, translucency at thin edges, and hardness sufficient to scratch glass; common sources include India, Brazil, and Uruguay. As a small polished piece, typical value is about $1–$10.