Septarian Crystal Bowl Home DecorSeptarian or Lightning Stone is a concretion of hard, compact mass of matter formed by the precipitation of mineral cement within the spaces between particles and is found in sedimentary rock or soil. Concretions are often ovoid or spherical in shape, although irregular shapes also occur. This bowl would make great home decor. You could display it on a mantel, on a coffee table, on a dresser and use it for change or jewelry, or you could even use it