gemstone

Tumbled carnelian

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

AI-generated identification · may be incorrect

Hardness 6.5–7 Mohs; reddish-brown to orange, with a smooth polish and waxy-to-vitreous luster. It has a cryptocrystalline quartz structure and no visible cleavage; the pieces appear to have drilled holes, possibly for beads.

Identified September 26, 2026More gemstone →

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Physical properties

Formation & geological history

Forms as iron-colored chalcedony in silica-rich cavities and veins, commonly in volcanic rocks. Carnelian deposits range from ancient to geologically recent; the image cannot establish the stones’ age or source.

Uses & applications

Used for beads, jewelry, carvings, and ornaments; historically valued as a carving stone and seal material.

Geological facts

Carnelian is chalcedony colored chiefly by iron oxide; heating can deepen or alter its orange-red color.

Field identification & locations

Recognize it by its translucent warm color, fine-grained texture, and hardness sufficient to scratch glass; common sources include India, Brazil, and Uruguay. The image shows polished pieces, so field features are not visible.