Septarian nodule. Cut and polished interior of a septarian nodule. This is a round mineral deposit of claystone (grey) filled with cracks formed when

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Septarian nodule. Cut and polished interior of a septarian nodule. This is a round mineral deposit of claystone (grey) filled with cracks formed when the claystone dried up. These cracks (brown) fill with other minerals (white), often calcite, a form of calcium carbonate. The variety of patterns that can form are often prized for their beauty.

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Size: 3840px × 4850px
Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: calcite, calcium, carbonate, clay, claystone, crack, cracks, crystal, crystals, cut, dried, earth, geological, geology, mineral, mud, nodule, pattern, patterned, patterns, polished, rock, rocks, science, section, sectioned, semi-precious, septarian, stone, surface