Rock Identifier
Horn Coral Fossil (Rugosa (solitary coral)) — fossil
fossil

Horn Coral Fossil

Rugosa (solitary coral)

AI-generated identification · may be incorrect

Mohs hardness of 3-4; color ranges from tan to grey; vitreous to dull luster; calcite composition with distinct septa radiating from the center.

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Physical properties

Mohs hardness of 3-4; color ranges from tan to grey; vitreous to dull luster; calcite composition with distinct septa radiating from the center.

Formation & geological history

Formed during the Paleozoic era, particularly the Ordovician to Permian periods, when solitary rugose corals secreted calcium carbonate skeletal structures in ancient shallow seas.

Uses & applications

Valued by fossil collectors, used in educational displays, and studied by paleontologists for paleoenvironmental reconstruction.

Geological facts

Rugose corals are called 'horn corals' due to their horn-like, conical shape, and they went extinct during the end-Permian mass extinction.

Field identification & locations

Identify by its conical, horn-like shape and internal radial ridges; commonly found in limestone deposits worldwide, especially in North America and Europe.

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