fossil

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with marine fossils

Hardness: 3-4 on Mohs scale. Color: Greyish-green to tan. Luster: Dull, earthy. Structure: Massive/biogenic sedimentary rock matrix containing fossil fragments. Cleavage: None (conchoidal to irregular fracture).

Hardness: 3-4 on Mohs scale
Color: Greyish-green to tan
Luster: Dull, earthy

Identified July 24, 2026More fossil →

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Physical properties

Formation & geological history

Formed in warm, shallow marine environments through the accumulation of organic debris such as coral, shell, and crinoid fragments over millions of years.

Uses & applications

Used in construction, cement production, soil conditioning, and as a popular decorative or educational specimen for fossil collectors.

Geological facts

Fossiliferous limestones often preserve ancient marine ecosystems, offering a window into prehistoric oceanic conditions and ancient lifeforms.

Field identification & locations

Identifiable by its reaction (fizzing) with dilute acid and the visible presence of fossilized marine organisms embedded in the fine-grained matrix.

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Phylum Echinodermata, Class Crinoidea

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Sedimentary bedrock formation (variable composition)

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Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

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Fossiliferous Limestone

Fossiliferous Calcilutite / Biomicrite

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Fossiliferous Limestone

Biogenic Limestone with Brachiopod/Crinoid fragments

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Fossilized Crinoid Stem in Limestone

Crinoidea (Class) in Calcium Carbonate (CaCO3) matrix

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