gemstone

Polished reddish-brown gemstone, likely carnelian

Carnelian: chalcedony, microcrystalline quartz (SiO₂), colored mainly by iron oxides

AI-generated identification · may be incorrect

Typically translucent orange-red to brown with waxy/vitreous luster, no visible cleavage, conchoidal fracture, and Mohs hardness 6.5–7. The pictured piece appears smoothly polished and cabochon-like, though its strong blur prevents certainty.

Identified September 20, 2026More gemstone →

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At a glance

Common name: Polished reddish-brown gemstone, likely carnelian
Scientific name: Carnelian: chalcedony, microcrystalline quartz (SiO₂), colored mainly by iron oxides
Category: gemstone
Identified: September 20, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a small common polished piece; $30–$150+ for larger, strongly translucent, naturally vivid, or fine-quality specimens.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Forms when silica-rich groundwater deposits chalcedony in cavities and fractures, with iron producing the red-brown color; deposits range from ancient volcanic-hosted veins to younger sedimentary environments.

Uses & applications

Used for cabochons, beads, carvings, ornaments, and small jewelry pieces; also collected as an attractive variety of chalcedony.

Geological facts

Carnelian is cryptocrystalline quartz rather than a separately crystallized mineral species. Color may be enhanced by heating, which converts iron compounds to deeper reds.

Field identification & locations

Common sources include India, Brazil, Uruguay, Madagascar, Germany, and the United States. Identify it by its even reddish color, translucency, hardness, and lack of cleavage; a scratch test should be avoided on finished pieces.