Rock Identifier
Fossilized Ammonite (Ammonoidea subclass) — fossil
fossil

Fossilized Ammonite

Ammonoidea subclass

AI-generated identification · may be incorrect

Hardness varies around 3-4 on Mohs scale depending on mineralization, featuring distinct chambered spiral shell structures with earthy or pearly luster.

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Physical properties

Hardness varies around 3-4 on Mohs scale depending on mineralization, featuring distinct chambered spiral shell structures with earthy or pearly luster.

Formation & geological history

Formed through permineralization of ancient marine cephalopod shells in shallow seas primarily during the Mesozoic era.

Uses & applications

Valued primarily as display specimens, educational tools, and in lapidary jewelry crafting.

Geological facts

Ammonites are classic index fossils used by geologists to date rock layers worldwide.

Field identification & locations

Found globally in marine sedimentary rock formations, especially in clay-rich strata and shale exposures.

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