Beach Stones with White Lines 7 – Natural pattern of crystalline calcite-filled cracks in a beach stone derived from the inner core of a Birchi Nodule from the Shales-with-Beef Member of the Charmouth Mudstone Formation of the Lower Lias in the Jurassic Period at Charmouth, Dorset, England. This inner core of a Birchi Nodule is also known as a septarian nodule.
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