gemstone

Tumbled Carnelian

Silicon Dioxide (Variety of Chalcedony), SiO2

AI-generated identification · may be incorrect

Hardness of 6.5 to 7 on the Mohs scale, reddish-orange to brown color, vitreous to waxy luster, microcrystalline (cryptocrystalline) crystal structure, conchoidal fracture with no true cleavage, and a specific gravity of roughly 2.58 to 2.64.

Identified August 3, 2026More gemstone →

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Physical properties

Formation & geological history

Formed in low-temperature hydrothermal environments, groundwater solutions, or as a secondary mineral in cavities of pre-existing volcanic and sedimentary rocks where silica-rich solutions precipitate.

Uses & applications

Widely used in jewelry making (rings, beads, pendants), carved into intaglios and signet rings historically, and collected as a lapidary specimen.

Geological facts

Carnelian has been prized as a gemstone for thousands of years, with archaeological evidence showing its use in ancient Minoan, Roman, and Ancient Egyptian cultures where it was often associated with royalty and the afterlife.

Field identification & locations

Can be identified by its characteristic translucent reddish-brown or orange color and waxy luster. Commonly sourced from Brazil, India, Madagascar, and the United States.