fossil

Goniatite Fossil

Order Goniatitida

Hardness of 3-4 (calcite/aragonite), color ranges from dark grey, black, to white, vitreous to dull luster, cephalopod shell structure, specific gravity around 2.6-2.7

Identified August 3, 2026More fossil →

Explore Goniatite Fossil in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness of 3-4 (calcite/aragonite), color ranges from dark grey, black, to white, vitreous to dull luster, cephalopod shell structure, specific gravity around 2.6-2.7

Formation & geological history

Formed during the Paleozoic era, particularly the Devonian to Permian periods (approx. 400 to 250 million years ago), where marine cephalopod shells were buried in sediment and mineralized via permineralization or replacement by calcite.

Uses & applications

Used as index fossils in geology for relative dating of rock strata, popular in decorative items, lapidary carvings, and collected by fossil enthusiasts.

Geological facts

Goniatites are an extinct group of shelled cephalopods related to modern squids, octopuses, and nautiluses. They are characterized by their simple, lobed suture lines visible on the shell.

Field identification & locations

Easily identified by their coiled, ammonoid-like shell with characteristic goniatitic suture patterns. Frequently found in limestone and marine sedimentary rock formations worldwide, notably in Morocco, North America, and Europe.