sedimentary

Rounded quartz-rich pebble, possibly chert or weathered sandstone

Indeterminate siliciclastic rock; likely microcrystalline quartz (SiO₂) or quartz-feldspar sandstone

AI-generated identification · may be incorrect

Small, water-rounded tan-brown pebble with a dull earthy luster and fine-grained texture. Estimated hardness is about 5–7 Mohs; no visible crystals or cleavage, and its exact identity cannot be confirmed from the photograph alone.

Identified August 26, 2026More sedimentary →

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At a glance

Common name: Rounded quartz-rich pebble, possibly chert or weathered sandstone
Scientific name: Indeterminate siliciclastic rock; likely microcrystalline quartz (SiO₂) or quartz-feldspar sandstone
Category: sedimentary
Identified: August 26, 2026
Method: Standard

AI Estimated Value

Typically $0–$5 as an ordinary pebble; potentially $5–$30 if confirmed as attractive jasper, chert, or another lapidary-grade material.

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

Likely formed as a sedimentary fragment and later rounded by stream, beach, or glacial transport; age is indeterminate and depends on its source formation.

Uses & applications

Common pebbles have little commercial value, though attractive chert or jasper varieties may be used for lapidary work, tumbling, cabochons, or small carvings.

Geological facts

The mottled tan color may reflect iron-oxide staining. A glassy fracture and ability to scratch glass would support chert or quartz-rich material; a gritty texture and weaker hardness would favor sandstone.

Field identification & locations

Commonly found in gravel beds, river channels, beaches, and glacial deposits. A hardness test, streak test, magnification, and fresh broken surface are needed for reliable identification.