fossil

Fossiliferous pebble, possibly a crinoid or shell fragment

Indeterminate bioclast in a dark sedimentary matrix; likely carbonate fossil material (calcite, CaCO₃)

AI-generated identification · may be incorrect

Small rounded dark-gray pebble with a contrasting cream, porous fossil-like inclusion. The matrix may be fine-grained limestone or chert; calcitic fossil material is Mohs 3 and commonly dull to slightly waxy, but hardness and acid reaction are unverified.

Identified August 30, 2026More fossil →

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At a glance

Common name: Fossiliferous pebble, possibly a crinoid or shell fragment
Scientific name: Indeterminate bioclast in a dark sedimentary matrix; likely carbonate fossil material (calcite, CaCO₃)
Category: fossil
Identified: August 30, 2026
Method: Standard

AI Estimated Value

About $1–$15 for an ordinary loose pebble; more if the fossil is confirmed and unusually well preserved.

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 formed when marine skeletal debris was buried, mineralized, and cemented in carbonate sediment, then rounded by erosion. Exact geological age cannot be determined from the photograph; marine Paleozoic–Mesozoic rocks are common possibilities.

Uses & applications

Primarily a teaching or collecting specimen; not suitable for construction or jewelry except as a polished curiosity. Typical value is modest.

Geological facts

The pale structure could be a crinoid segment, shell fragment, or weathered coral, but the image is insufficient for confident identification.

Field identification & locations

Look for repeated chambers, radial symmetry, or shell growth lines; a dilute hydrochloric-acid test may fizz on calcite. Common sources include marine limestone gravels and fossil-bearing coastal or river deposits.