Ammonite on sliding machine

This ammonite from Madagascar is a Cleoniceras . It dates from the Cretaceous, about 120 million years ago. It is remarkable, because it has mineralized with chambers crystalized with calcite caramel: the most beautiful! . It is sawn in 2 and mounted on a rack mechanism with a metal base. The first chambers filled with grey clay had undergone a small hole in the shell with the movements of the waves : the bottom of the Jurassic sea was able to enter these chambers. By activating these brass gears, we can discover the complexity of the interior and even calculate its age! It grew from a partition all moon phases: 29.5 days, under optimal conditions. A scientific curiosity... but especially aesthetic!