fossil

Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion

Calcareous concretion; exact fossil and host-rock composition are not identifiable from the image

AI-generated identification · may be incorrect

A rounded, rough, pale outer mass surrounds a smooth gray-brown cross-section with a light central patch. Likely carbonate-rich; hardness and crystal structure cannot be reliably determined from appearance alone.

Identified October 3, 2026More fossil →

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At a glance

Common name: Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion
Scientific name: Calcareous concretion; exact fossil and host-rock composition are not identifiable from the image
Category: fossil
Identified: October 3, 2026
Method: Standard

AI Estimated Value

Approximately $5–$30 for a common, unidentified specimen; more if a well-preserved fossil is confirmed.

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

Concretions form when minerals cement sediment around a nucleus during burial. The specimen’s geological age and precise depositional setting cannot be established visually.

Uses & applications

Primarily a collector’s or educational specimen; carbonate concretions may also be studied to understand sedimentary processes.

Geological facts

The circular pattern may be a fossil or mineral-filled feature, but a cut surface or closer examination would be needed to identify it confidently.

Field identification & locations

Look for a distinct fossil structure, sedimentary layering, and a boundary between the concretion and surrounding rock; avoid damaging it before identification. Concretions occur in sedimentary formations worldwide.