fossil

Weathered fossiliferous limestone, likely coral or shell fragment

Calcite (CaCO₃), biogenic limestone; exact fossil taxon indeterminate from the image

AI-generated identification · may be incorrect

Cream to tan, porous and irregular, with a dull to faintly earthy luster and visible fossil-like cavities. Calcite hardness is Mohs 3; it commonly effervesces strongly with dilute hydrochloric acid and has no consistent cleavage in this weathered fragment.

Identified September 8, 2026More fossil →

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At a glance

Common name: Weathered fossiliferous limestone, likely coral or shell fragment
Scientific name: Calcite (CaCO₃), biogenic limestone; exact fossil taxon indeterminate from the image
Category: fossil
Identified: September 8, 2026
Method: Standard

AI Estimated Value

Typically $1-$10 for an unidentified fragment; $10-$50 if clearly identifiable, attractive, or legally 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 from accumulated marine skeletal material later lithified into limestone; the visible piece may be a weathered coral or mollusk fragment. Its age cannot be determined from the photograph and may range from Paleozoic to recent geological deposits.

Uses & applications

Primarily a curiosity, teaching specimen, or fossil collection piece; limestone is widely used for cement, aggregate, soil amendment, and building stone, but this small fragment has negligible practical value.

Geological facts

Porosity and curved internal structures suggest biological origin rather than an igneous or metamorphic rock. Acid testing and magnification can help distinguish coral, shell, and ordinary porous limestone.

Field identification & locations

Common in marine sedimentary formations, beaches, quarries, and fossil beds worldwide. Examine for repeated coral corallites or shell growth lines; avoid destructive testing unless permitted.