mineral

Polished/tumbled chalcedony (likely agate or jasper)

Microcrystalline quartz, SiO₂; possibly quartz-rich silicified material

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; cream, honey-yellow, white, and brown coloration with waxy to dull luster and no obvious cleavage. The irregular, partly polished surface and granular patches suggest chalcedony mixed with opaque jasper or weathered matrix.

Identified September 6, 2026More mineral →

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At a glance

Common name: Polished/tumbled chalcedony (likely agate or jasper)
Scientific name: Microcrystalline quartz, SiO₂; possibly quartz-rich silicified material
Category: mineral
Identified: September 6, 2026
Method: Standard

AI Estimated Value

About $5–$30 as a common rough or tumbled specimen; $30–$100+ if it has attractive patterns, provenance, or high-quality lapidary polish.

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 fills cavities, fractures, or porous volcanic rock, later hardening into chalcedony and agate/jasper. Precise geological age and locality cannot be determined from the photograph.

Uses & applications

Used for ornamental stones, cabochons, carvings, beads, and lapidary specimens; lower-grade pieces have modest collecting value.

Geological facts

Agate is banded chalcedony, whereas jasper is opaque and commonly contains iron oxides or other impurities; this specimen appears more jasper-like than a clean agate.

Field identification & locations

Field identification: glassy or waxy appearance, conchoidal fracture, lack of cleavage, and inability to scratch it with a steel knife; quartz should scratch ordinary glass. Common worldwide, especially volcanic regions and river gravels.