Natural septarian stone specimen from Madagascar measuring 9" long and 6" across. 

Septarian nodules originated during the Cretaceous period somewhere between 50-70 million years ago. The name is derived from the word "septum", meaning "portion", due to the fact that the Limestone mud masses from which it forms have dried and cracked into distinctive shapes before filling with dark brown aragonite crystal. Much of the folklore tied to Septarian proclaims that it bestows confidence to those in possession of it.