Ammonite main content.


Part of Grand Gallery.

Ammonite_Grand Gallery © AMNH/C. Chesek

Ammonite fossils are an incredible source of information for scientists, from dating rocks to confirming the presence of prehistoric seas. These extinct marine animals thrived in the Paleozoic and Mesozoic Eras, some 400 to 65 million years ago.

The vivid coloration of this ammonite is unique to ammonites from Alberta, Canada. Its iridescence is probably due to high temperatures and pressures during fossilization.