fossil

Fossiliferous Limestone

Biomicrite / Fossiliferous Limestone (CaCO3)

AI-generated identification · may be incorrect

Hardness 3 (Mohs scale), tan to cream color with visible shell fragments, dull luster, effervesces in weak acid, contains secondary calcite crystals.

Identified July 14, 2026More fossil →

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Physical properties

Hardness 3 (Mohs scale), tan to cream color with visible shell fragments, dull luster, effervesces in weak acid, contains secondary calcite crystals.

Formation & geological history

Formed in warm, shallow marine environments from the accumulation of calcium carbonate shells and skeletal remains of marine organisms, later lithified by pressure and mineral cement.

Uses & applications

Used primarily in the production of cement, crushed stone for road construction, lime for soil treatment, and by fossil enthusiasts for educational collections.

Geological facts

This specimen contains distinct shell impressions and cross-sections of ancient marine mollusks or brachiopods, preserving a snapshot of an ancient seabed ecosystem.

Field identification & locations

Identify by looking for visible fossil imprints or shell fragments in a fine-grained matrix; can be scratched with a penny and reacts to white vinegar. Common in sedimentary basins worldwide.