Keywords: Concretion01.jpg en Concretion with septarian cracks filled with calcite Scale in mm Photograph taken by Mark A Wilson Department of Geology The College of Wooster Wilson44691 2008-07 Photograph taken by Mark A Wilson Department of Geology The College of Wooster http //www3 wooster edu/geology/MWilson html Pseudofossils Concretion Objects with black background |