Polished Ammonite Split Pair - 3.461" Cleoniceras mm3 Ancient sea urchins

Ancient sea urchins

the Sikhote Alin meteorite is one of the largest meteorite falls observed in recorded history

The exposed tooth measures 2

70" fossil fragment of the Dimetrodon's iconic spine

One collection

Polished Ammonite Split Pair - 3.461" Cleoniceras mm3 Ancient sea urchinsAmmonites are an extinct group of cephalopods that entered the fossil record 400 million years ago. This specimen is a 3. 461" polished Cleoniceras fossil from Madagascar. The fossil has been split into a paired set to showcase the beautiful internal chambers of the shell. These internal chambers are called septa and the ammonite could fill them with air in order to float through the ocean like a balloon. After millions of years, they are now