sedimentary

Rounded quartz-rich river pebble

Likely quartz-rich sandstone or quartzite pebble; composition chiefly SiO₂ with possible feldspar and mica

AI-generated identification · may be incorrect

Gray-beige, fine-grained, dull to subtly sugary/sparkly luster, with no visible cleavage; quartz hardness is about Mohs 7, while sandstone varies roughly 6–7 and quartzite is 7. The smooth rounded shape indicates water abrasion.

Identified August 14, 2026More sedimentary →

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At a glance

Common name: Rounded quartz-rich river pebble
Scientific name: Likely quartz-rich sandstone or quartzite pebble; composition chiefly SiO₂ with possible feldspar and mica
Category: sedimentary
Identified: August 14, 2026
Method: Standard

AI Estimated Value

Typically $0–$5 as a common natural pebble; perhaps $5–$20 if unusually attractive, polished, or locally 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 derived from weathered quartz-rich bedrock and transported in a stream or beach environment; its exact geological age cannot be determined from the photograph. If quartzite, it formed by metamorphic recrystallization of sandstone; if sandstone, by sediment burial and cementation.

Uses & applications

Commonly used as landscaping gravel, aggregate, decorative stone, and lapidary material; this ordinary pebble has little commercial value.

Geological facts

The pale granular sparkle and uniform texture are consistent with abundant quartz. A steel file or knife should scratch sandstone more readily than quartzite, while quartz-rich surfaces resist scratching.

Field identification & locations

Look for interlocking grains and very high toughness to identify quartzite; visible loose grains or slight porosity suggest sandstone. Common in riverbeds and glacial deposits worldwide.