Rock Identifier
Rugose Coral Fossil (Order Rugosa) — fossil
fossil

Rugose Coral Fossil

Order Rugosa

AI-generated identification · may be incorrect

Hardness varies around 3-4 on the Mohs scale depending on mineralization, typically calcite or silica. Exhibits radial symmetry, a horn-like curved shape, and visible internal septa.

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Physical properties

Hardness varies around 3-4 on the Mohs scale depending on mineralization, typically calcite or silica. Exhibits radial symmetry, a horn-like curved shape, and visible internal septa.

Formation & geological history

Formed during the Paleozoic era, ranging from the Ordovician to the Permian period, as marine organisms secreted calcium carbonate skeletons in ancient shallow seas.

Uses & applications

Used primarily in fossil collecting, educational displays, and occasionally in lapidary jewelry.

Geological facts

Also commonly known as horn coral due to its distinctive horn-like external shape. They went extinct during the Permian-Triassic extinction event.

Field identification & locations

Found in ancient limestone and shale deposits worldwide. Easily identified by its horn shape and distinct internal septal walls exposed on weathered ends.

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Weathered fossil bone fragment (identification uncertain)

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