sedimentary

Fossiliferous Limestone

Limestone with embedded fossil cross-section

AI-generated identification · may be incorrect

Hardness of ~3 (calcite matrix), gray to brownish-gray color, dull luster, massive structure with embedded fossil. The white circular shape is a cross-section of a fossil, likely a shell or stem.

Identified May 31, 2026More sedimentary →

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Physical properties

Hardness of ~3 (calcite matrix), gray to brownish-gray color, dull luster, massive structure with embedded fossil. The white circular shape is a cross-section of a fossil, likely a shell or stem.

Formation & geological history

Formed in marine environments from the accumulation of calcium carbonate and organic remains (shells, coral, algal debris) over millions of years.

Uses & applications

Limestone is used extensively in construction, cement manufacturing, and agriculture. Fossiliferous specimens are collected by hobbyists and educators.

Geological facts

The distinct white ring is a cross-section of a fossilized organism, possibly a crinoid stem or a bivalve/gastropod shell, which got buried in calcareous mud that later lithified into rock.

Field identification & locations

Identify by its reaction (fizzing) with dilute hydrochloric acid. Commonly found in areas that were once shallow ancient seas. For collectors, the presence of distinct fossils adds interest.