metamorphic

Tumbled reddish-brown pebble, likely iron-stained quartzite or sandstone

Probable quartzite (mostly SiO₂), though sandstone or chert is also possible from the photograph

AI-generated identification · may be incorrect

Hardness likely Mohs 6.5–7 for quartzite; opaque salmon-brown, fine-grained, smooth rounded surface, and dull to slightly waxy luster. No visible cleavage or distinct crystals; iron-oxide staining likely causes the color.

Identified September 8, 2026More metamorphic →

Explore Tumbled reddish-brown pebble, likely iron-stained quartzite or sandstone in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

At a glance

Common name: Tumbled reddish-brown pebble, likely iron-stained quartzite or sandstone
Scientific name: Probable quartzite (mostly SiO₂), though sandstone or chert is also possible from the photograph
Category: metamorphic
Identified: September 8, 2026
Method: Standard

AI Estimated Value

About $1–$10 as a common tumbled pebble; up to roughly $10–$30 if unusually attractive, polished, or sold as a curated specimen.

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

If quartzite, it formed when quartz-rich sandstone was compressed and recrystallized during metamorphism, commonly hundreds of millions to billions of years ago. Its rounded shape indicates stream, beach, or deliberate tumbling abrasion.

Uses & applications

Suitable as a decorative pebble, landscaping stone, craft material, or low-cost lapidary specimen; generally little jewelry value unless it has attractive patterns or unusual provenance.

Geological facts

Quartzite commonly resists scratching and weathering better than sandstone. The image alone cannot reliably distinguish quartzite from iron-rich sandstone, chert, or another siliciclastic pebble.

Field identification & locations

Test with a steel knife: quartzite should resist scratching; a glass-scratch test is more diagnostic but may damage the surface. Common worldwide in river gravels, beaches, and glacial deposits.