Rock Identifier
Horn Coral Fossil (Rugosa) — fossil
fossil

Horn Coral Fossil

Rugosa

AI-generated identification · may be incorrect

Mohs hardness of 3 to 4, typically gray, white, or brown with a horn-like, conical shape and radial internal structures. Luster is dull to vitreous.

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Physical properties

Mohs hardness of 3 to 4, typically gray, white, or brown with a horn-like, conical shape and radial internal structures. Luster is dull to vitreous.

Formation & geological history

Formed during the Paleozoic era, around 250 to 500 million years ago, through the mineralization of solitary coral skeletal remains in ancient shallow seas.

Uses & applications

Used primarily as educational specimens, decorative items, and by fossil collectors.

Geological facts

Rugose corals are called 'horn corals' due to their distinctive horn-like curved shape, and they went extinct during the Permian-Triassic extinction event.

Field identification & locations

Identify by its distinct conical, horn-like shape and visible septa (internal radial walls). Found worldwide in limestone and sedimentary rock formations from the Paleozoic.

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