fossil

Fossiliferous Limestone

Calcium carbonate matrix with macrofossils (CaCO3)

Hardness: 3 on Mohs scale (matrix), Color: Grayish-brown with lighter fossil fragments, Luster: Dull to earthy, Cleavage: None (conchoidal to irregular fracture), Specific Gravity: 2.5-2.7.

Identified July 26, 2026More fossil →

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Physical properties

Hardness: 3 on Mohs scale (matrix), Color: Grayish-brown with lighter fossil fragments, Luster: Dull to earthy, Cleavage: None (conchoidal to irregular fracture), Specific Gravity: 2.5-2.7.

Formation & geological history

Formed in warm, shallow marine environments through the accumulation of organic debris, shells, and skeletal fragments of marine organisms over millions of years.

Uses & applications

Used in construction, cement manufacturing, soil conditioning, and highly sought after by amateur paleontologists and fossil collectors.

Geological facts

Fossiliferous limestone often contains fossilized remains of ancient marine life such as brachiopods, crinoids, bryozoans, and mollusks, preserving prehistoric ocean ecosystems.

Field identification & locations

Can be identified in the field by its reactiveness to dilute hydrochloric acid (fizzing) and the presence of visible shell-like structures embedded in a fine-grained matrix.

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Crinoid Stem Fossil in Matrix

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Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

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Fossilized Crinoid Stem in Limestone

Crinoidea (Class) in Calcium Carbonate (CaCO3) matrix

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Fossiliferous Limestone

Limestone with embedded fossil cross-section

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Fossiliferous Calcilutite / Biomicrite

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