fossil

Fossilized bivalve shell

Fossil mollusk, likely an oyster or similar bivalve; original shell composed of calcium carbonate (aragonite/calcite)

AI-generated identification · may be incorrect

Small, layered, ridged shell fragment with tan-brown coloration and a dull to slightly satin luster. Fossil shells are typically Mohs 3–4, though mineral replacement may increase hardness; visible growth lines and symmetrical valve curvature are diagnostic.

Identified September 3, 2026More fossil →

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At a glance

Common name: Fossilized bivalve shell
Scientific name: Fossil mollusk, likely an oyster or similar bivalve; original shell composed of calcium carbonate (aragonite/calcite)
Category: fossil
Identified: September 3, 2026
Method: Standard

AI Estimated Value

About $2–$15 for a small common specimen; higher only with confirmed species, locality, rarity, or exceptional preservation.

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 bivalve shell was buried in sediment and preserved through compaction, mineralization, or partial replacement, likely during the Cenozoic or late Mesozoic; exact age requires locality and laboratory study.

Uses & applications

Primarily a collectible, educational, or decorative specimen; fossil shell material is occasionally used in crafts, but this example has little commercial value.

Geological facts

The concentric bands record episodic shell growth and environmental changes. Fossilization can preserve original shell mineralogy or replace it with calcite, silica, or iron oxides.

Field identification & locations

Identify it by layered growth rings, shell-like curvature, and fossil texture rather than crystalline grains. Common in marine limestone, coastal deposits, and sedimentary formations worldwide.