fossil

Beach-worn fossil bone or coral fragment

Indeterminate biogenic calcium-carbonate material; likely fossilized bone (hydroxyapatite) or coral (calcite/aragonite)

AI-generated identification · may be incorrect

Pale gray, porous, and strongly rounded by abrasion, with rusty-brown staining. Apparent hardness is roughly 3–5.5 Mohs depending on whether it is carbonate or mineralized bone; luster is dull and structure is irregular rather than crystalline.

Identified August 30, 2026More fossil →

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At a glance

Common name: Beach-worn fossil bone or coral fragment
Scientific name: Indeterminate biogenic calcium-carbonate material; likely fossilized bone (hydroxyapatite) or coral (calcite/aragonite)
Category: fossil
Identified: August 30, 2026
Method: Standard

AI Estimated Value

Typically $1–$20 for an unidentified common fragment; verified, attractive, or scientifically documented fossils may sell for $20–$100+.

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 weathered fossil or skeletal fragment altered by burial mineralization and later beach or sediment abrasion; its geological age cannot be determined from the image. The pores and curved form suggest bone or coral rather than an ordinary rock.

Uses & applications

Primarily a collecting specimen or teaching aid; not suitable for construction or jewelry without cutting and stabilization.

Geological facts

The shape and surface texture are consistent with a fragment of porous skeletal material, but image-only identification cannot distinguish bone from coral or weathered limestone confidently.

Field identification & locations

Check for internal cellular pores, layered coral walls, or bone-like canals; a vinegar test may fizz if carbonate is present, though testing can damage it. Common sources include beaches, limestone exposures, and sedimentary deposits.