fossil

Fossiliferous Limestone / Fossil Fragment

Calcium Carbonate (CaCO3) with indeterminate biogenic remains

Hardness: 3 on Mohs scale (calcite matrix); Color: Pale greyish-green to tan and beige; Luster: Earthy, dull; Structure: Microcrystalline matrix enclosing irregular organic/fossil molds or inclusions; Specific Gravity: ~2.5-2.7

Hardness: 3 on Mohs scale (calcite matrix)
Color: Pale greyish-green to tan and beige
Luster: Earthy, dull

Identified July 24, 2026More fossil →

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Physical properties

Formation & geological history

Formed in warm, shallow marine or estuarine depositional environments where calcium carbonate accumulated alongside organic marine debris and shell material. Over time, compaction and cementation lithified the sediments into solid rock.

Uses & applications

Educational purposes, amateur fossil collecting, landscape stone, and crushed stone aggregate in construction.

Geological facts

Fossiliferous limestone often contains impressions or permineralized remains of ancient marine organisms like crinoids, brachiopods, or bivalves. Weathering often highlights these ancient structures against the softer matrix.

Field identification & locations

Look for small cavities, curved shell-like impressions, and a characteristic effervescent reaction when tested with dilute hydrochloric acid. Commonly found in exposed limestone bedrock formations, stream beds, and quarries.

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