These unusual rock formations are called septarians. A septarian is a mud concretion that formed on an ancient seabed or floor. These nodules or concretions were formed 50 million to 70 million years ago. In very rare instances fossil remains of various ocean floor dwellers may be found inside the septarian. Theories vary as to what caused the crystals to form inside. Scientists do agree that the process of formation is very unusual and complex.
Septarians usually have a pattern of jagged veins on the inside. The different minerals that make up the septarian include yellow calcite, brown aragonite, white or clear barite with grey rock called limestone forming the nodule. The septarian may be solid or it may contain a hollow cavity that is filled with calcite crystals. The hollow septarians are sometimes called septarian geodes.
A lot of work goes into digging septarians, as well as into cutting, polishing, and preparing the pieces for display.
- Dimensions: 163 mm x 182 mm x 13 mm
- Genuine fossil.
- This item includes an information card about the fossil.
- A certificate of authenticity is included with this item.
- A plastic stand is included with this item.
This fossil requires special care - exposure to water and other chemicals, such as cleaning products or aerosols, will damage it over time. If you polish the stone, use a dry cloth only, or an air duster that does not contain any disinfectant or other chemicals.