fossil

Fossil-bearing limestone, likely coral or shell limestone

Bioclastic calcarenite/calcirudite; predominantly calcium carbonate (CaCO₃), commonly calcite

AI-generated identification · may be incorrect

Cream to gray, highly weathered and porous, with visible fossil fragments and possible coralline structure; calcite has Mohs hardness 3, vitreous to earthy luster, rhombohedral cleavage, and reacts vigorously with dilute hydrochloric acid or vinegar.

Identified August 29, 2026More fossil →

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At a glance

Common name: Fossil-bearing limestone, likely coral or shell limestone
Scientific name: Bioclastic calcarenite/calcirudite; predominantly calcium carbonate (CaCO₃), commonly calcite
Category: fossil
Identified: August 29, 2026
Method: Standard

AI Estimated Value

Typically $2–$20 for a common hand specimen; $20–$100+ if the fossil structures are unusually clear, identifiable, 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

Formed from accumulated marine shells, coral, and skeletal debris that lithified into limestone, likely during a shallow-marine Phanerozoic setting; the exact age cannot be determined from the image.

Uses & applications

Used as aggregate, cement and lime feedstock, building stone, and educational or fossil-collecting specimens; this small weathered piece has limited commercial value.

Geological facts

The rounded cavities and irregular fossil textures may represent dissolved shells or colonial coral, but an exact fossil identification requires a clearer surface and locality information.

Field identification & locations

Common in marine sedimentary formations worldwide, especially former reefs and shallow seas. Confirm limestone with acid effervescence; avoid acid testing if preservation is important.