mineral

Tumbled chalcedony (likely jasper/chert variety)

Microcrystalline quartz, SiO₂ (chalcedony; opaque varieties commonly called jasper or chert)

AI-generated identification · may be incorrect

Hardness 6.5–7 Mohs; cream, tan, gray, and lavender coloration with waxy to vitreous luster. It has cryptocrystalline quartz structure, no visible cleavage, conchoidal fracture, and typical specific gravity near 2.6.

Identified September 15, 2026More mineral →

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At a glance

Common name: Tumbled chalcedony (likely jasper/chert variety)
Scientific name: Microcrystalline quartz, SiO₂ (chalcedony; opaque varieties commonly called jasper or chert)
Category: mineral
Identified: September 15, 2026
Method: Standard

AI Estimated Value

$3–$15 for a common tumbled piece; $20–$75 if unusually patterned, translucent, or sold as quality jasper/chalcedony.

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

Silica-rich groundwater filled cavities, fractures, or sediments and crystallized as microcrystalline quartz, generally during or after volcanic or sedimentary activity. The rounded, glossy surface indicates human tumbling and polishing.

Uses & applications

Used for beads, cabochons, carvings, decorative stones, and lapidary practice; jasper and chalcedony are popular but generally modestly priced gemstones.

Geological facts

Chalcedony is a collective lapidary term for fibrous or granular microcrystalline quartz; color zoning and inclusions often produce attractive patterns.

Field identification & locations

Identify by its hardness, waxy appearance, lack of cleavage, and inability to scratch with a steel blade easily; common sources include Brazil, Madagascar, India, Mexico, and the western United States. A precise variety requires a fresh surface or testing for translucency and pattern.