fossil

Likely fossiliferous limestone fragment

Calcareous fossil assemblage, chiefly calcium carbonate (CaCO₃), possibly crinoid, bivalve, or bryozoan material in limestone

AI-generated identification · may be incorrect

Gray to tan, dull-to-waxy luster, irregular weathered surface with apparent fossil textures; calcite hardness Mohs 3, commonly reacts with dilute hydrochloric acid. Exact identification is limited by the photograph.

Identified September 15, 2026More fossil →

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At a glance

Common name: Likely fossiliferous limestone fragment
Scientific name: Calcareous fossil assemblage, chiefly calcium carbonate (CaCO₃), possibly crinoid, bivalve, or bryozoan material in limestone
Category: fossil
Identified: September 15, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a common fragment; $30–$100+ if the fossils are clearly identifiable, well preserved, or locality-documented.

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 when marine carbonate shells and skeletal debris accumulated, lithified, and later weathered or were exposed; age could range from Paleozoic to Cenozoic depending on locality.

Uses & applications

Primarily a collectible or educational specimen; fossil limestone is also used as aggregate, cement feedstock, and dimension stone, though this small piece has no practical industrial use.

Geological facts

The visible patterned impressions may represent fossil fragments rather than mineral crystals; a close examination of the broken surface and acid reaction would help distinguish fossil limestone from a mineral concretion.

Field identification & locations

Common in former shallow-marine sedimentary basins worldwide, including the United States, Europe, and North Africa. Look for repeated biological forms, carbonate matrix, and fizzing in acid; avoid acid testing on valuable specimens.