sedimentary

Reddish-brown rounded pebble, likely iron-stained sandstone or chert

Probable quartz-rich sandstone (SiO₂), possibly ferruginous chert; exact identification requires testing

AI-generated identification · may be incorrect

Fine-grained, opaque reddish-brown surface with a dull to slightly earthy luster and rounded water-worn shape. Likely hardness about 6–7 Mohs if quartz-rich; cleavage absent and specific gravity approximately 2.5–2.7.

Identified August 11, 2026More sedimentary →

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At a glance

Common name: Reddish-brown rounded pebble, likely iron-stained sandstone or chert
Scientific name: Probable quartz-rich sandstone (SiO₂), possibly ferruginous chert; exact identification requires testing
Category: sedimentary
Identified: August 11, 2026
Method: Standard

AI Estimated Value

Typically $1–$10 as an ordinary pebble; up to about $10–$30 if unusually attractive, polished, or demonstrably collectible.

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

Probably formed as quartz-rich sedimentary rock cemented by silica or iron oxides, then weathered and rounded in a stream or shoreline environment. Its precise geological age cannot be determined from the photograph.

Uses & applications

Common examples are used as decorative stones, landscaping aggregate, and occasionally lapidary material; this individual specimen has little practical value.

Geological facts

The reddish color commonly comes from hematite or limonite coatings and cement. A glassy streak or conchoidal fracture would favor chert, while visible sand grains would favor sandstone.

Field identification & locations

Common in sedimentary terrains and gravel deposits worldwide. Test with a steel knife or glass, inspect a fresh fracture, and use dilute acid only if carbonate minerals are suspected; photographic identification is uncertain.