A fine example of two Audoliceras heteromorph ammonites. Audoliceras were a type of cephalopod that swam in our oceans much like the common squid and modern nautilus. Both ammonites display opalescence and iridescence throughout the nacre of the shell - famous characteristics of mineralisation in the Tartar region of Russia. Chitin is a natural element within the shell before the mineralisation process begins which helps this unique effect, caused by mineral deposits of the fossiliferous layers of the Jurassic period in this particular region. Now laying upon this quartz bedrock.
Details
Genus: Audoliceras heteromorph
Age: Mesozoic era, Cretaceous period, 135 to 65 million years
Origin: Volga River Formation, Saratov, Ulyanovsk region, Russia
R. Audoliceras: L: 22 cm / W: 5.2 cm
L. Audoliceras: L: 20.3 cm / W: 5.2 cm
Overall: H: 24 cm / W: 34.5 cm / D: 20.5 cm / KG: 9.234
