mineral

Tumbled brown stone, possibly chert or iron-stained quartzite

Indeterminate from photograph; possible microcrystalline quartz (SiO₂)

AI-generated identification · may be incorrect

Smooth, rounded, opaque brown specimen with a dull to weakly waxy luster; likely hardness about 6.5–7 Mohs if chert or quartzite. No visible crystals, cleavage, or layering; specific gravity may be approximately 2.6–2.7.

Identified August 26, 2026More mineral →

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At a glance

Common name: Tumbled brown stone, possibly chert or iron-stained quartzite
Scientific name: Indeterminate from photograph; possible microcrystalline quartz (SiO₂)
Category: mineral
Identified: August 26, 2026
Method: Standard

AI Estimated Value

Typically $1–$10 for a small common tumbled specimen; higher only if testing confirms an attractive variety or unusual 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

Could be naturally rounded or mechanically tumbled from silica-rich rock, with brown coloration caused by iron oxides. The formation age and locality cannot be determined visually.

Uses & applications

Commonly used as a decorative tumbled stone, craft material, or lapidary specimen; not identifiable as a gem-quality material from this image.

Geological facts

Chert and quartzite resist weathering and commonly produce smooth pebbles; iron staining can range from yellow-brown to reddish brown.

Field identification & locations

Test hardness against glass: scratching glass supports quartz-rich material, while a steel nail should not scratch it. A streak, specific-gravity, and close examination for grain texture are needed to distinguish chert, quartzite, jasper, or another brown stone.