mineral

Tumbled quartz-rich pebble, possibly calcite or quartzite

Most likely microcrystalline quartz (SiO₂); carbonate identification would require testing

AI-generated identification · may be incorrect

Cream-white, opaque, dull to weakly waxy luster, rounded and naturally or artificially smoothed; quartz hardness ~7, while calcite is ~3, with no obvious cleavage visible.

Identified September 12, 2026More mineral →

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At a glance

Common name: Tumbled quartz-rich pebble, possibly calcite or quartzite
Scientific name: Most likely microcrystalline quartz (SiO₂); carbonate identification would require testing
Category: mineral
Identified: September 12, 2026
Method: Standard

AI Estimated Value

Approximately $1–$10 as an ordinary pebble or craft specimen; potentially $10–$30 if testing reveals an attractive collectible mineral.

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

Cream-white, opaque, dull to weakly waxy luster, rounded and naturally or artificially smoothed; quartz hardness ~7, while calcite is ~3, with no obvious cleavage visible.

Formation & geological history

Likely a weathered river or beach pebble, or a tumbled specimen; quartz-rich material formed from silica-bearing igneous or metamorphic rocks, whereas calcite could derive from limestone. Exact age and identity cannot be determined from the image alone.

Uses & applications

Common quartz pebbles are used for landscaping, crafts, and inexpensive collections; calcite specimens are used ornamentally and industrially, while neither appears gem quality here.

Geological facts

The surface shows irregular cream-colored patches and fractures but no diagnostic crystal faces. A steel knife or glass scratch test, vinegar reaction, and streak test can distinguish likely calcite from quartz.

Field identification & locations

Check whether it scratches glass (quartz) or is scratched by a knife and fizzes in vinegar (calcite); a fresh unweathered surface and hardness test are more reliable than color. Common worldwide in alluvial deposits.