fossil

Fossiliferous limestone with possible ammonite or shell impressions

Calcitic limestone, chiefly CaCO₃; fossils may include ammonoids or bivalves

AI-generated identification · may be incorrect

Pale gray to beige, dull to earthy luster, fine-grained carbonate matrix with raised and recessed fossil molds. Calcite-rich limestone is Mohs hardness 3 and typically reacts vigorously with dilute hydrochloric acid; exact identification requires close examination and acid testing.

Identified August 21, 2026More fossil →

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At a glance

Common name: Fossiliferous limestone with possible ammonite or shell impressions
Scientific name: Calcitic limestone, chiefly CaCO₃; fossils may include ammonoids or bivalves
Category: fossil
Identified: August 21, 2026
Method: Standard

AI Estimated Value

Approximately $10–$75 as an ordinary hand specimen; potentially $100–$300+ if a well-identified, legally collected, scientifically significant fossil is exposed.

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

Marine sediment accumulated on an ancient seafloor, later compacted and cemented; the fossils likely date from the Paleozoic or Mesozoic, but the geological age cannot be established from the image alone. Fossil cavities formed after shells dissolved or weathered out.

Uses & applications

Used as aggregate, cement and building stone; attractive fossiliferous pieces are collected or displayed, though this specimen appears primarily a teaching/curio specimen rather than jewelry material.

Geological facts

The circular and curved structures may be shell sections, burrows, or weathered concretions; a polished face or professional preparation would be needed for confident fossil identification.

Field identification & locations

Look for consistent shell symmetry, growth lines, chambers, or septa rather than random cavities; limestone commonly occurs in marine sedimentary sequences worldwide. Value is strongly determined by fossil certainty, locality, preparation, and completeness.