fossil

Fossiliferous limestone (probable coral or shell fossil)

Calcite-rich limestone, primarily calcium carbonate (CaCO₃); the circular patterns may be fossil structures

AI-generated identification · may be incorrect

Gray-white, dull to slightly pearly surface with rounded fossil-like markings; likely calcite, Mohs hardness 3, typically reacts with dilute acid. Exact texture and fossil identity cannot be confirmed from the image alone.

Identified October 10, 2026More fossil →

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At a glance

Common name: Fossiliferous limestone (probable coral or shell fossil)
Scientific name: Calcite-rich limestone, primarily calcium carbonate (CaCO₃); the circular patterns may be fossil structures
Category: fossil
Identified: October 10, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a common hand-sized fossiliferous limestone specimen; more if fossils are unusually clear or identifiable.

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

Formed from carbonate sediment and marine skeletal remains deposited in a shallow sea, then compacted and cemented; age depends on its source locality and cannot be determined visually.

Uses & applications

Used as building and ornamental stone, and as a source of lime and cement; fossiliferous pieces are mainly collected for display.

Geological facts

The repeated round markings may be coral or other marine fossils preserved in the limestone.

Field identification & locations

Look for identifiable shells, coral patterns, and fizzing under dilute acid; limestone is widespread in ancient marine sedimentary basins. Keep the specimen dry and avoid acids if preserving it.