From the Oxfordian stage of the Jurassic period (Kimmeridge Clay). These beautiful irridescent ammonites measure from 1/2" to 2" across. They were found on a stream bed near Swindon, Wiltshire, England. Nearby we found large specimens of the ammonite 'Pictonia' (10" across) but that's another story!
Collected, washed and photographed by Neville.