Beach Stones with White Lines 8 – Natural pattern of crystalline calcite-filled cracks in a beach stone probably derived from the inner cores of a Birchi Nodules from the Shales-with-Beef Member of the Charmouth Mudstone Formation of the Lower Lias in the Jurassic Period at Charmouth, Dorset, England. The inner core of Birchi Nodules are also known as a septarian nodules.
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