fossil

Fossil-rich limestone

Bioclastic limestone, likely containing bivalve or brachiopod fossils; calcium carbonate (CaCO₃), chiefly calcite

AI-generated identification · may be incorrect

Typically tan to gray, earthy to dull luster, and composed of cemented shell fragments; calcite has Mohs hardness 3, rhombohedral cleavage, and reacts strongly with dilute hydrochloric acid. The specimen shows abundant irregular fossil impressions and shell-like structures in a carbonate matrix.

Identified August 16, 2026More fossil →

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At a glance

Common name: Fossil-rich limestone
Scientific name: Bioclastic limestone, likely containing bivalve or brachiopod fossils; calcium carbonate (CaCO₃), chiefly calcite
Category: fossil
Identified: August 16, 2026
Method: Standard

AI Estimated Value

$10-$40 for a common hand specimen; approximately $50-$150 or more if fossils are well-preserved, scientifically identified, and 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 shells and skeletal debris accumulated on an ancient seafloor, were compacted, and cemented. The exact geologic age cannot be determined from the image; such limestone ranges from Paleozoic to Cenozoic in age.

Uses & applications

Used as building stone, aggregate, cement and lime feedstock; attractive fossiliferous pieces are mainly used for education, display, and collecting rather than jewelry.

Geological facts

The visible fossils may include brachiopods, bivalves, corals, or gastropods, but species-level identification requires close examination and locality information. Limestone commonly preserves shallow-marine ecosystems exceptionally well.

Field identification & locations

Identify it by its dense carbonate matrix, visible fossils, and fizzing in dilute acid; avoid confusing it with concrete, which usually contains uniformly distributed modern aggregate. Common worldwide in former marine sedimentary basins.