sedimentary

Rounded pebble (likely quartz-rich sandstone or weathered chert)

Indeterminate from image; possibly quartz (SiO₂)-rich lithic material

AI-generated identification · may be incorrect

Small, water-worn, tan-gray pebble with a dull to slightly earthy luster and no visible crystals or cleavage. Apparent hardness is likely about 6–7 Mohs if chert/quartz-rich, but cannot be confirmed visually.

Identified September 12, 2026More sedimentary →

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At a glance

Common name: Rounded pebble (likely quartz-rich sandstone or weathered chert)
Scientific name: Indeterminate from image; possibly quartz (SiO₂)-rich lithic material
Category: sedimentary
Identified: September 12, 2026
Method: Standard

AI Estimated Value

Typically less than $1; approximately $1–$10 if unusually attractive, polished, or associated with a documented locality.

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 naturally weathered and rounded by stream, beach, or glacial transport; its original rock may be sedimentary and potentially millions to hundreds of millions of years old. Exact formation age and process require testing.

Uses & applications

Common pebbles have little commercial value, though attractive examples may be used in crafts, landscaping, terrariums, or teaching collections.

Geological facts

The photograph is insufficient for a definitive mineral or rock identification; scale, weight, texture, streak, and hardness testing would help distinguish chert, sandstone, quartzite, and ordinary river stone.

Field identification & locations

Test whether it scratches glass (approximately 5.5 Mohs), examine grain size with magnification, and check for acid reaction; chert is very fine-grained, while sandstone shows visible grains. Similar pebbles occur in river gravels and beaches worldwide.