fossil

Fossil bivalve shell

Fossilized or mineral-replaced bivalve mollusk shell; exact genus/species requires locality and detailed morphology

AI-generated identification · may be incorrect

Hardness about 3–4 Mohs if calcitic, with cream-to-brown coloration, pearly to dull luster, layered shell growth lines, and aragonite/calcite originally. The thick, curved valve and hinge region are characteristic of a clam or related bivalve.

Identified September 13, 2026More fossil →

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At a glance

Common name: Fossil bivalve shell
Scientific name: Fossilized or mineral-replaced bivalve mollusk shell; exact genus/species requires locality and detailed morphology
Category: fossil
Identified: September 13, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a common, unidentified specimen; $50–$200+ if exceptionally preserved, large, or taxonomically and geographically documented.

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 preserved by burial, compaction, and partial mineralization or recrystallization, commonly in limestone or marine sediment. Its geological age cannot be determined from the image alone; it may range from Paleozoic to recent fossil-bearing deposits.

Uses & applications

Primarily a collectible, educational, or decorative specimen; fossil shell material is not generally used industrially or as gemstone jewelry.

Geological facts

The specimen appears to be a single valve rather than a complete paired shell. Brown coloration commonly results from iron staining, sediment, or mineral replacement.

Field identification & locations

Look for bilateral shell symmetry, a hinge/umbo, growth rings, and internal nacre or muscle-scar features; common sources include marine limestones and coastal fossil beds worldwide. Avoid acid testing if preservation is valuable, since calcite dissolves in dilute acid.