Description
Red ammonite fossil from Madagascar. Patterns and colours may not be exactly as shown.
Ammonites are an extinct group of marine animals in the Cephalopoda class. Red ammonites display red flash, which is opalized, or iridescent. The unusual coloration of these ammonites is caused by light passing through layers of aragonite and conchiolin built up in the animal during its life cycle, then preserved through fossilization.
