Photo By Gail

This shell is an Ammonite, a marine animal that went extinct at the same time as most dinosaurs, around 65 million years ago. The shell’s spectacular coloration is unusual and is found only in ammonites from Alberta, Canada, such as this one. For many millions of years, the shell was subject to high temperatures and pressures, which produced the iridescent effect.

Photographed in the Museum of Natural History in NYC.