sedimentary

Fossiliferous limestone fragment

Calcite-rich limestone, predominantly CaCO₃

AI-generated identification · may be incorrect

Usually cream to tan, with a dull to subtly crystalline luster; Mohs hardness 3, poor cleavage, and specific gravity about 2.3–2.7. The exposed cut surface appears pale, fine-grained, and possibly contains fossil or shell material.

Identified August 23, 2026More sedimentary →

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Physical properties

Formation & geological history

Forms when marine or freshwater carbonate mud, shells, and skeletal debris accumulate and lithify, commonly during the Paleozoic–Cenozoic eras. Weathering or cutting has exposed the lighter interior.

Uses & applications

Used for cement, agricultural lime, crushed stone, and dimension stone; attractive fossiliferous pieces are collected or used decoratively. This small fragment has minimal commercial value.

Geological facts

Calcite limestone effervesces vigorously with cold dilute hydrochloric acid or household vinegar, though a weak reaction may indicate dolomite or surface alteration. The image alone cannot confirm a specific fossil or locality.

Field identification & locations

Look for visible shell fragments, bedding, and acid reaction; it is softer than quartz and can be scratched with a steel knife. Common worldwide, especially in former shallow-marine basins.