Septarian Dragon Egg
Septarian Dragon Eggs, also known as Septarian nodules, were formed around 50 to 70 million years ago as a result of volcanic eruptions. Dead sea life was chemically attracted to the sediment around it forming mud balls which, when the ocean receded, dried up. Due to their bentonite content they also shrank in size, creating the cracks inside. Septarian comes from the Latin "septem" meaning seven because the mud balls tended to crack in 7 points in every direction, creating the distinct pattern these nodules exhibit.