fossil

Fossiliferous limestone

Bioclastic limestone, likely containing fossil gastropods or other marine invertebrates; mainly calcite (CaCO₃)

AI-generated identification · may be incorrect

Typically Mohs hardness 3, dull to earthy luster, cream-brown color, and irregular massive texture. Visible spiral and shell-like impressions suggest embedded or weathered fossil remains; calcite may effervesce with dilute hydrochloric acid.

Identified August 14, 2026More fossil →

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At a glance

Common name: Fossiliferous limestone
Scientific name: Bioclastic limestone, likely containing fossil gastropods or other marine invertebrates; mainly calcite (CaCO₃)
Category: fossil
Identified: August 14, 2026
Method: Standard

AI Estimated Value

Approximately $10–$50 for a common hand specimen; $75–$200+ if the fossils are unusually clear, large, or from a documented locality.

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 accumulated marine shells and carbonate mud that lithified into limestone, commonly during Paleozoic–Cenozoic shallow-marine deposition; the exact age cannot be determined from the photograph.

Uses & applications

Used as a decorative or educational specimen and occasionally as aggregate or cement raw material; fossil-rich pieces have modest collector interest.

Geological facts

The rounded spiral patterns may represent gastropods, ammonites, or molds rather than intact shells. Weathering can preferentially dissolve shell material and leave cavities or casts.

Field identification & locations

Look for repeated shell geometry, granular carbonate matrix, and acid fizz; distinguish it from ordinary limestone by its abundant fossil structures. Common in former shallow-sea sediments worldwide, including the Mediterranean, Middle East, Europe, and North America.