gemstone

Carnelian (orange chalcedony), possibly fire agate

Microcrystalline quartz, SiO₂ (chalcedony variety)

AI-generated identification · may be incorrect

Translucent honey-orange to reddish-brown, waxy/glassy luster, no visible crystals, conchoidal fracture, and hardness about 6.5–7 Mohs; the cloudy white zone may be quartz or agate banding. The surface appears naturally rough or lightly polished.

Identified August 30, 2026More gemstone →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater fills cavities and fractures in volcanic rocks, with iron oxides producing orange-red color; commonly Cenozoic to older volcanic-hosted material. The image alone cannot confirm fire-agate iridescence or treatment.

Uses & applications

Used for cabochons, beads, carvings, and ornamental objects; attractive translucent pieces are valued by lapidaries and collectors.

Geological facts

Carnelian is a chalcedony variety colored chiefly by iron. Fire agate is a related chalcedony containing thin iron-oxide layers that can show iridescent flashes when viewed from different angles.

Field identification & locations

Identify by translucent orange color, waxy luster, quartz-like hardness, and conchoidal fracture; common sources include India, Brazil, Uruguay, Madagascar, and Mexico. A scratch test or loupe examination can distinguish it from amber, resin, or glass.