sedimentary

Rounded white pebble, likely quartzite or limestone

Probable quartzite (microcrystalline quartz, SiO₂) or calcitic limestone (CaCO₃)

AI-generated identification · may be incorrect

Small, water-worn, pale-white specimen with a dull to weakly waxy luster and fine-grained texture; apparent hardness is roughly Mohs 3–7 depending on composition. No visible crystals or cleavage; image resolution prevents definitive identification.

Identified September 7, 2026More sedimentary →

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At a glance

Common name: Rounded white pebble, likely quartzite or limestone
Scientific name: Probable quartzite (microcrystalline quartz, SiO₂) or calcitic limestone (CaCO₃)
Category: sedimentary
Identified: September 7, 2026
Method: Standard

AI Estimated Value

Typically $0–$5 as an ordinary pebble; up to about $5–$20 if unusually attractive, provenance-specific, or part of a curated collection.

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 rounded by stream, beach, or glacial abrasion. Quartzite formed when sandstone was metamorphosed; limestone formed by accumulation and lithification of carbonate sediment, commonly over millions to hundreds of millions of years.

Uses & applications

Usually collected as a curiosity, craft stone, or decorative pebble; quartzite can be used as aggregate and building stone, while limestone is widely used for cement, lime, and construction.

Geological facts

Scratch testing and acid testing distinguish the possibilities: quartzite scratches glass and does not fizz in dilute hydrochloric acid; calcitic limestone fizzes strongly but cannot scratch glass.

Field identification & locations

Test an inconspicuous spot with a steel blade, glass, and a drop of vinegar or dilute acid; inspect the powder and texture. Commonly found in river gravels, beaches, and glacial deposits.