sedimentary

Rounded gray pebble, likely limestone or weathered sandstone

Probably micritic limestone (calcite, CaCO₃) or quartz-rich sandstone; exact identification requires testing

AI-generated identification · may be incorrect

Fine-grained, gray-beige, dull to faintly sugary luster, rounded by water abrasion; likely hardness 3 if limestone or 6–7 if sandstone, with no visible cleavage or crystals

Identified September 4, 2026More sedimentary →

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At a glance

Common name: Rounded gray pebble, likely limestone or weathered sandstone
Scientific name: Probably micritic limestone (calcite, CaCO₃) or quartz-rich sandstone; exact identification requires testing
Category: sedimentary
Identified: September 4, 2026
Method: Standard

AI Estimated Value

Usually $0–$5 as a common field pebble; modestly higher only if confirmed unusual, fossiliferous, or attractively patterned

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

Fine-grained, gray-beige, dull to faintly sugary luster, rounded by water abrasion; likely hardness 3 if limestone or 6–7 if sandstone, with no visible cleavage or crystals

Formation & geological history

A sedimentary clast eroded from bedrock and rounded in a stream, beach, or gravel deposit. Its depositional age cannot be determined from the photograph

Uses & applications

Commonly used as landscaping or decorative stone; not typically valuable for jewelry or industry as an individual pebble

Geological facts

The pale speckling may be calcite grains, quartz, or weathered surface material. A drop of dilute hydrochloric acid or vinegar can reveal carbonate limestone by fizzing, though weak vinegar may be inconclusive

Field identification & locations

Test streak, hardness, and acid reaction: limestone may scratch with a knife and fizz; sandstone resists scratching and usually does not fizz. Common worldwide in riverbeds, beaches, and glacial gravels