fossil

Fossilized sea-shell fragment, likely belemnite or rudist-like carbonate fossil

Indeterminate calcitic fossil in limestone; possible belemnite rostrum (Belemnitida)

AI-generated identification · may be incorrect

Gray-beige, irregular, partly crystalline carbonate with a pointed taper and weathered surface. Likely calcite (Mohs 3), dull to weakly pearly luster, no reliable cleavage visible; reacts with dilute hydrochloric acid if carbonate-rich. The shape is suggestive but not diagnostic from this view.

Identified August 16, 2026More fossil →

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At a glance

Common name: Fossilized sea-shell fragment, likely belemnite or rudist-like carbonate fossil
Scientific name: Indeterminate calcitic fossil in limestone; possible belemnite rostrum (Belemnitida)
Category: fossil
Identified: August 16, 2026
Method: Standard

AI Estimated Value

About $2–$20 as an unidentified fragment; $20–$100 if confirmed as a well-preserved, identifiable belemnite or other fossil.

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 organism’s calcitic hard parts were buried in carbonate sediment and lithified, commonly during the Mesozoic. The Rhône-region rocks near 45.9°N, 4.8°E include sedimentary formations, so a carbonate fossil is geologically plausible, though exact age cannot be determined visually.

Uses & applications

Primarily a paleontological/collector specimen; carbonate fossil material may be used decoratively when polished, but this piece has little industrial value.

Geological facts

Belemnite fossils are internal shells of extinct squid relatives and commonly preserve a tapered, bullet-like rostrum. Other possibilities include a broken bivalve or heavily weathered limestone concretion.

Field identification & locations

Look for repeating growth lines, chamber structure, or a radial/central cross-section; a fresh surface and acid test help distinguish calcite from quartz. Common regional alternatives include Jurassic–Cretaceous marine limestone fossils, but professional identification may require the underside and a scale reference.