fossil

Fossilized shell or bone fragment

Likely bioclast composed mainly of calcium carbonate (calcite/aragonite); exact organism is indeterminate from the image

AI-generated identification · may be incorrect

Cream-white, matte to weakly waxy, with layered/ridged biological texture and irregular fracture; likely Mohs hardness 3–4, specific gravity about 2.6–2.8. Effervesces in dilute hydrochloric acid if calcitic, though some fossil material may be silicified and nonreactive.

Identified August 23, 2026More fossil →

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At a glance

Common name: Fossilized shell or bone fragment
Scientific name: Likely bioclast composed mainly of calcium carbonate (calcite/aragonite); exact organism is indeterminate from the image
Category: fossil
Identified: August 23, 2026
Method: Standard

AI Estimated Value

About $1–$15 for a small unidentified fragment; $20–$100+ if identified, complete, attractive, or from a documented 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 biological shell or skeletal fragment was buried in sediment and mineralized during diagenesis, commonly in marine limestone; age cannot be determined visually and may range from Paleozoic to Recent.

Uses & applications

Primarily a collecting, educational, and decorative specimen; not generally suitable for construction or jewelry unless exceptionally complete, patterned, or polished.

Geological facts

The visible concentric ridges and porous-looking broken surface are characteristic of fossilized biological material rather than an ordinary crystalline mineral.

Field identification & locations

Look for repeated growth lines, symmetry, pores, or internal chambers; compare with local fossil guides and test a hidden spot with dilute acid. Common in sedimentary exposures, limestone quarries, beaches, and gravel deposits.