fossil

Fossiliferous limestone pebble (probable coral or shell fossil)

Calcite (CaCO₃), commonly biogenic limestone; exact fossil taxon indeterminate from the image

AI-generated identification · may be incorrect

Tan-brown, fine-grained, dull to slightly waxy surface with raised fossil-like organic textures; calcite hardness 3, vitreous to earthy luster, generally massive with no visible cleavage. Effervesces strongly with dilute hydrochloric acid or vinegar, especially on a freshly scratched surface.

Identified August 26, 2026More fossil →

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At a glance

Common name: Fossiliferous limestone pebble (probable coral or shell fossil)
Scientific name: Calcite (CaCO₃), commonly biogenic limestone; exact fossil taxon indeterminate from the image
Category: fossil
Identified: August 26, 2026
Method: Standard

AI Estimated Value

$1–$15 as an unidentified pebble; approximately $10–$75 if professionally identified, attractive, and demonstrably fossil-bearing.

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

A fossil-bearing carbonate sediment formed from marine shells, skeletal debris, or coral that accumulated on an ancient seafloor, lithified, and later weathered into a rounded pebble. Its precise geological age cannot be determined visually.

Uses & applications

Primarily a collector or educational specimen; limestone is widely used for cement, aggregate, building stone, and agricultural lime, while fossils may have display value.

Geological facts

The apparent looping and cellular relief may represent fossilized biological structures rather than crystal patterns, but surface weathering can mimic fossils.

Field identification & locations

Look for consistent cellular, spiral, or shell geometry and acid reaction; compare with local fossil-bearing limestone. Common in former shallow-marine sedimentary regions and gravel deposits.