Fully Pyritiferous Fossil Ammonite found in the Volga River Formation, Russia…
Polished limestone from Marston Magna, U.K. with a calcite vein which runs across the fossil. This piece shows many cross-sections of ammonites (Promicroceras marsdonensis). Jurassic period, approximately 200 million years old.
Ammonite,Sphenodiscus lenticularis, from the Fox Hills Formation, South Dakota.Both sides display intricate suture patterns and an iridescent nacreous layer. This laterally flattened Ammonite is thought to be a fast swimmer.
pearl-nautilus: “ Sphenodiscus lenticularis, Fox Hills Formation, South Dakota Late Cretaceous (~ 70 mya) This specimen displays the extraordinarily intricate suture patterns that are characteristic of this species. Also evident is part of the.