sedimentary

Tumbled jasper/chert pebble (likely orbicular or brecciated jasper)

Microcrystalline quartz (SiO₂), with iron-oxide and other mineral impurities

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; opaque, smoothly rounded, waxy to dull luster, gray-green, cream, tan, and reddish-brown coloration with dark iron- or manganese-oxide patches. Massive, non-cleaving cryptocrystalline quartz; specific gravity about 2.6.

Identified September 15, 2026More sedimentary →

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At a glance

Common name: Tumbled jasper/chert pebble (likely orbicular or brecciated jasper)
Scientific name: Microcrystalline quartz (SiO₂), with iron-oxide and other mineral impurities
Category: sedimentary
Identified: September 15, 2026
Method: Standard

AI Estimated Value

About $2–$15 as a common tumbled stone; roughly $20–$75 for a larger, unusually patterned or locality-labeled specimen.

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

Formed when silica-rich groundwater replaced or cemented fine sediment, commonly incorporating iron oxides and volcanic or clay impurities; later rounded naturally or by tumbling. Exact age and locality cannot be determined from the photograph.

Uses & applications

Used as ornamental stone, cabochons, beads, polished specimens, and decorative aggregate; attractive pieces typically have stronger pattern contrast and polish.

Geological facts

Jasper is an opaque variety of chalcedony or microcrystalline quartz, and its colors commonly reflect iron, manganese, chlorite, or clay minerals. The specimen appears human-tumbled or naturally water-worn rather than freshly fractured.

Field identification & locations

Identify by its opaque appearance, very fine texture, waxy polish, and inability to scratch glass only variably depending on surface weathering; it should resist a steel knife. Common sources include volcanic terrains and silica-rich gravels worldwide.