sedimentary

Rounded river pebble, likely quartz-rich chert or fine-grained sandstone

Indeterminate lithic clast; possible microcrystalline quartz (chert) or quartz-rich sandstone

AI-generated identification · may be incorrect

Small, naturally water-worn oval with dull earthy gray-brown color, fine texture, and subvitreous to dull luster. Hardness is approximately 6–7 if chert, or 5–6 if sandstone; no obvious cleavage or visible crystals.

Identified September 8, 2026More sedimentary →

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At a glance

Common name: Rounded river pebble, likely quartz-rich chert or fine-grained sandstone
Scientific name: Indeterminate lithic clast; possible microcrystalline quartz (chert) or quartz-rich sandstone
Category: sedimentary
Identified: September 8, 2026
Method: Standard

AI Estimated Value

Typically $0–$3 as an individual pebble; up to about $5–$15 if unusually attractive, locality-specific, or part of a curated collection.

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 produced by weathering and abrasion in a stream, beach, or glacial deposit; its original sedimentary rock may be millions to hundreds of millions of years old, but age cannot be determined from the photograph.

Uses & applications

Usually a common collecting pebble with negligible commercial value; suitable for crafts, landscaping, or educational reference, but not typically used as an ornamental stone.

Geological facts

The pale speckles and uniform fine grain are compatible with chert, silicified sediment, or weathered quartz-rich sandstone. A scratch test and fresh broken surface would substantially improve identification.

Field identification & locations

Common in stream gravels and beaches worldwide. Chert should scratch glass and resist a steel knife; sandstone is more porous and may shed grains, while dilute acid generally causes no reaction unless carbonate cement is present.