gemstone

Polished carnelian agate

Carnelian, a red-orange variety of chalcedony (microcrystalline quartz, SiO₂)

AI-generated identification · may be incorrect

Typically Mohs 6.5–7; translucent orange to reddish-brown, waxy to vitreous luster, with no visible crystals and no cleavage. The specimen is polished and rounded; its banding may indicate agate chalcedony.

Identified October 11, 2026More gemstone →

Explore Polished carnelian agate in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Silica-rich fluids deposited quartz in rock cavities, often in volcanic settings; iron oxides impart the orange-red color. Such deposits formed across many geological ages.

Uses & applications

Used for beads, cabochons, ornamental objects, and jewelry; historically carved into seals and cameos.

Geological facts

Carnelian is a traditional gemstone and has been used in jewelry and seals since antiquity.

Field identification & locations

Look for warm orange-red translucence, waxy luster, and hardness sufficient to resist scratching with a steel knife. Chalcedony occurs worldwide, including Brazil, India, Uruguay, and the United States.