Septarian Nodule Stone Sphere Decorator Rock
A large hand cut, 3.25 inches or 84 mm in diameter, beautiful Septarian Nodule stone sphere from Utah.
This material was formed when the Gulf of Mexico extended into what is now Southern Utah. Decomposing sea life (especially seashells) had molecular attraction for the sediment surrounding them, forming mud balls. As the ocean receded, the balls dried and cracked. The oceans returned, depositing more sediments. Aragonite then formed on the edges of the cracks and yellow Calcite crystals formed in the spaces.
The name comes from the Aragonite dividing ("septurn" in Latin) the calcite from the clay.
This sphere does not have any crystal pockets. It does have some natural surface pits and a surface flaw visible on the far right of the 3rd picture.