fossil

Fossil shell fragment

Likely a fossilized bivalve or brachiopod valve; exact identification requires the other valve, locality, and matrix

AI-generated identification · may be incorrect

White to cream, ribbed shell form with preserved radial ornamentation; likely calcite (CaCO₃), Mohs hardness about 3, pearly to dull luster, and strong cleavage in calcite. The apparent dark background is likely a display surface rather than matrix.

Identified September 21, 2026More fossil →

Explore Fossil shell fragment in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

At a glance

Common name: Fossil shell fragment
Scientific name: Likely a fossilized bivalve or brachiopod valve; exact identification requires the other valve, locality, and matrix
Category: fossil
Identified: September 21, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a common fragment; $50–$200+ if complete, scientifically identified, well-preserved, 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 and mineralized during diagenesis, potentially replacing or preserving the original calcium-carbonate shell. Geological age cannot be determined from the image alone; fossil shells range from Paleozoic to Recent.

Uses & applications

Primarily a collector or educational specimen; fossil shell material is not generally used for construction or jewelry unless polished or set decoratively.

Geological facts

The ribbed, asymmetric shape may indicate a brachiopod, while shell curvature and ornament could indicate a bivalve. White coloration commonly reflects recrystallized calcite or aragonite alteration.

Field identification & locations

Identify it by hinge structure, symmetry, growth lines, and whether ribs radiate from a beak or umbo; locality and associated rock are essential. Common fossil-shell sources include marine sedimentary rocks worldwide.