fossil

Fossilized shell fragment, likely brachiopod or bivalve

Calcareous fossil; commonly calcite/aragonite (CaCO₃), but exact taxon is uncertain from the image

AI-generated identification · may be incorrect

Gray-beige, rough and weathered, with a granular dull-to-waxy luster and possible shell ribbing. Calcite is Mohs 3, commonly pale gray to cream, and effervesces in dilute hydrochloric acid; the original shell may have recrystallized.

Identified August 23, 2026More fossil →

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At a glance

Common name: Fossilized shell fragment, likely brachiopod or bivalve
Scientific name: Calcareous fossil; commonly calcite/aragonite (CaCO₃), but exact taxon is uncertain from the image
Category: fossil
Identified: August 23, 2026
Method: Standard

AI Estimated Value

About $2–$15 for a common loose fragment; $20–$100+ if taxonomically identifiable, complete, or from a notable 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

A marine shell was buried in carbonate sediment and mineralized during diagenesis, often in Paleozoic–Mesozoic limestone. The rounded surface reflects weathering or transport after exposure.

Uses & applications

Primarily a collecting, educational, and display specimen; fossil limestone may also be used as aggregate or building stone, though this small piece has no industrial use.

Geological facts

The paired, ear-like form and faint radial texture are consistent with a small brachiopod or bivalve, but the visible surface is insufficient for confident identification.

Field identification & locations

Look for bilateral shell symmetry, hinge structures, ribs, and matching valves; test suspected calcite with dilute acid and avoid damaging the specimen. Similar fossils occur in marine limestones worldwide.