sedimentary

Fossiliferous limestone, likely crinoidal limestone

Bioclastic limestone; predominantly calcite (CaCO₃), with possible dolomite and silicate impurities

AI-generated identification · may be incorrect

Gray-brown, fine-to-coarse granular stone with scattered pale fossil fragments and possible crinoid ossicles; dull to slightly crystalline luster, massive texture, and no obvious cleavage. Mohs hardness 3; specific gravity about 2.6–2.8; effervesces strongly with dilute hydrochloric acid or vinegar if calcitic.

Identified August 19, 2026More sedimentary →

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At a glance

Common name: Fossiliferous limestone, likely crinoidal limestone
Scientific name: Bioclastic limestone; predominantly calcite (CaCO₃), with possible dolomite and silicate impurities
Category: sedimentary
Identified: August 19, 2026
Method: Standard

AI Estimated Value

$2–$15 as a common loose specimen; approximately $20–$75 if fossils are unusually clear or the piece is polished.

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

Formed from accumulated marine skeletal debris that was compacted and cemented on an ancient shallow seafloor, commonly during the Paleozoic–Mesozoic eras. The visible rounded shape is likely from later weathering or stream transport.

Uses & applications

Used as aggregate, cement and lime feedstock, building stone, and decorative material; attractive fossil-rich pieces are collected or polished, though this specimen is not typically gem-quality.

Geological facts

The pale flecks may represent crinoid fragments, brachiopods, or other marine fossils, but the photograph is insufficient for precise identification. A fresh broken surface and acid test would provide stronger confirmation.

Field identification & locations

Common in marine sedimentary regions, including the central and eastern United States, the UK, and Europe. Look for fossil patterns, granular calcite, and acid reaction; avoid confusing it with weathered marble or dolostone.