fossil

Fossiliferous limestone slab

Bioclastic limestone, chiefly calcite (CaCO₃), with possible shell or coral fragments

AI-generated identification · may be incorrect

Hardness about 3 (calcite); cream, tan, brown, and gray coloration with a weathered earthy luster, layered texture, and irregular fracture. The dark edges and mottled surface suggest fossil-rich carbonate rock rather than a crystalline mineral.

Identified September 12, 2026More fossil →

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Physical properties

Formation & geological history

Formed from accumulated marine shells, skeletal debris, or carbonate mud that lithified into limestone, commonly during the Paleozoic–Cenozoic eras. Exact age and fossil identity require locality and close examination.

Uses & applications

Used as a decorative or educational fossil specimen; limestone is widely used for cement, aggregate, building stone, and agricultural lime. Collector value is generally modest unless fossils are exceptionally preserved or identifiable.

Geological facts

Calcite-bearing limestone commonly reacts vigorously with dilute hydrochloric acid or household vinegar, especially on a freshly scratched surface. Surface weathering can make fossil textures difficult to recognize.

Field identification & locations

Look for visible shell, coral, or skeletal patterns, relatively low hardness, and acid effervescence; a knife may scratch it. Common in former shallow-marine sedimentary basins worldwide, including Europe, North America, and Asia.