Collection: Prehistoric Seas

A coiled ammonite genus that thrived across Jurassic seas roughly 165 million years ago, prized today for the intricate ribbing fossilized into its shell.

Despite the name, it isn’t a true nautilus at all - females secrete a papery, calcified shell purely to cradle their eggs, discarding it once they’re grown.

An Early Jurassic ammonite known for its sharply keeled, disc-like shell, now found fossilized in the marine clays of Western Europe.

A heteromorph ammonite that abandoned the classic spiral for a helical, corkscrew-shaped shell - proof that evolution doesn’t always coil in a straight line.

A Cretaceous-era ammonite from Madagascar’s fossil beds, its cross-section often polished to reveal a natural mosaic of calcite chambers.