fossil

Fossilized cylindrical shell or bone fragment

Indeterminate biogenic carbonate or phosphatic fossil; possible fragment of a tubular shell (e.g., scaphopod) or hollow bone

AI-generated identification · may be incorrect

Small, weathered, gray-brown hollow cylinder with rough granular surface and broken ends; mineral composition and hardness cannot be confirmed visually, likely calcite or apatite, Mohs ~3–5. No obvious crystal faces or metallic luster.

Identified August 10, 2026More fossil →

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At a glance

Common name: Fossilized cylindrical shell or bone fragment
Scientific name: Indeterminate biogenic carbonate or phosphatic fossil; possible fragment of a tubular shell (e.g., scaphopod) or hollow bone
Category: fossil
Identified: August 10, 2026
Method: Standard

AI Estimated Value

Typically $1–$15 if unidentified; approximately $20–$100+ if professionally identified, proven fossil material.

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

Likely a naturally fossilized biological tube or bone, formed when mineral-rich groundwater replaced or filled original tissue during burial; age and geologic formation cannot be determined from the image.

Uses & applications

Primarily a teaching or collecting specimen; scientific value depends on identifying its biological origin and geological context, while commercial value is usually minimal.

Geological facts

The regular tubular shape and hollow interior suggest biological structure rather than an ordinary rock, but it could also be a modern bone or shell fragment. Acid testing, microscopy, and contextual examination are needed for confirmation.

Field identification & locations

Check for internal septa, growth lines, pores, or a consistent shell wall; calcite fossils may fizz weakly in dilute hydrochloric acid. Common fossil localities include marine limestone and river gravels; avoid destructive testing without documentation.