This uncommonly large Septarian nodule half displays multiple aesthetic contraction grooves. This half has been finely polished to show an inner beauty as gray Limestone, yellow Calcite, and brown Aragonite interplay forming an orchestrated combination of complementary hues. Septarian nodules are basically a clay concretion that has had its hollow cavities filled with mineral rich fluids over thousands of years which crystalized over time and preserved the cracked patterns seen here. The stand will come for free The diameter is 31 cm.