Opalescent Fire Ammonite cleoniceras 9cm across
This is an excellent example of the incredibly colourful Opalescent Fire Ammonite. This polished Ammonite of the species cleoniceras measures 9cm across. This superb example shows the stunning iridescent red opal like lustre. The mineral aragonite replaced the ammonite shell, millions of years ago also creating these remarkable colours. This specimen dates back to the Cretaceous period, 120 million years ago. The stunning fiery red opalescence mean these fossils are also known as ‘Fire Ammonites’. These ammonites come from the North West Coast of Madagascar in the Mahajanga jungle.
Ammonites have been extinct for 65 million years, and were a form of Cephalopod, a group of marine molluscs. These first appeared in the Devonian Period, over 4oo million years ago. As ammonite grew larger they also added new chambers to their shell, with the actual mollusc only living in the largest and newest chamber. The name Ammonite, derives from from ‘Ammon’ the Greek God. Ammonites were plankton feeders, with long tentacles, and they also swam upright. Altogether, there were in the region of four thousand different species. Ammonites became extinct 65 million years ago. The squid, octopus and also cuttlefish that swim in our seas now however, are close relations.