fossil

Fossil bivalve shell

Likely an internal mold or mineralized shell of a brachiopod or small bivalve; exact taxonomy requires locality and diagnostic details

AI-generated identification · may be incorrect

Cream-white, irregularly ribbed, and weathered, with a dull to slightly pearly luster. The original carbonate shell is likely calcite or aragonite; calcite hardness is about 3 Mohs, with good cleavage and specific gravity near 2.7.

Identified August 8, 2026More fossil →

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At a glance

Common name: Fossil bivalve shell
Scientific name: Likely an internal mold or mineralized shell of a brachiopod or small bivalve; exact taxonomy requires locality and diagnostic details
Category: fossil
Identified: August 8, 2026
Method: Standard

AI Estimated Value

Typically $2-$20 for a common small specimen; $25-$100 or more if exceptionally preserved, identifiable, 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

A marine organism’s shell was buried in sediment and preserved by mineralization or left as a sediment-filled mold. Age cannot be determined from the photograph; such fossils range from Paleozoic to Cenozoic deposits.

Uses & applications

Primarily a teaching and collecting specimen; fossil shells may be used in educational displays and limited decorative work, but this small piece has no industrial use.

Geological facts

The strong concentric/radial ridges and asymmetric shell-like form indicate a biological origin rather than an ordinary mineral crystal.

Field identification & locations

Look for paired-valve symmetry, hinge features, ribs, growth lines, and carbonate reaction to dilute hydrochloric acid. Common in marine limestone, shale, and beach deposits worldwide; avoid acid testing if preservation is valuable.