This stunning septarian concretion nodule fossil is split to reveal the unique pattern that was created on the inside. Each half has a polished face that is 2.0 inches in length and 1.3 inches in width. These are from Morocco.
Septarian nodule (or septarian concretions) are the result of decomposing sea life that sank to the bottom of the ocean and attracted sea floor sediments, which created these nodules or mudballs. These are composed of calcite and were formed about 50 to 70 million years ago, about the time of the Cretaceous period.