sedimentary

Fossil-bearing limestone

Bioclastic limestone, chiefly calcite (CaCO₃), with embedded bivalve or brachiopod fossils

AI-generated identification · may be incorrect

Gray, fine- to medium-grained stone with pale shell-like fossil impressions or cross-sections; calcite has Mohs hardness 3, vitreous to dull luster, rhombohedral cleavage, and reacts vigorously with dilute hydrochloric acid. The specimen appears naturally weathered and rounded.

Identified September 5, 2026More sedimentary →

Explore Fossil-bearing limestone in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

At a glance

Common name: Fossil-bearing limestone
Scientific name: Bioclastic limestone, chiefly calcite (CaCO₃), with embedded bivalve or brachiopod fossils
Category: sedimentary
Identified: September 5, 2026
Method: Standard

AI Estimated Value

About $5–$25 for a common hand specimen; $30–$100+ if the fossils are exceptionally preserved, 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

Forms when marine shells and skeletal debris accumulate, are compacted, and cemented in shallow seas; age may range from Paleozoic to Cenozoic and cannot be determined reliably from the image alone.

Uses & applications

Used as crushed aggregate, cement and lime feedstock, building stone, and decorative or educational fossil material; this modest hand specimen has primarily collecting value.

Geological facts

Visible fossils appear to be shell fragments or molds, making the rock bioclastic rather than purely chemical limestone. Fossil identification requires clearer details and locality information.

Field identification & locations

Identify by its gray carbonate matrix, fossil fragments, relatively low hardness, and acid reaction; common in former marine sedimentary basins worldwide. Avoid vinegar for a definitive test if preservation matters; use dilute HCl on an inconspicuous spot.