Chert nodules in chalk. Chert is a fine-grained silica-rich sedimentary rock. These nodules formed by concretionary enrichment of the silica (silicon

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Chert nodules in chalk. Chert is a fine-grained silica-rich sedimentary rock. These nodules formed by concretionary enrichment of the silica (silicon dioxide) after the chalk had been deposited in marine environments.

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Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
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Keywords: -life, accumulation, calcium, carbonate, chalk, chemical, chemistry, chert, close-, concretion, concretionary, concretions, detail, dioxide, earth, enriched, environment, formation, formations, geographical, geography, geological, geology, life, marine, mineral, mineralogy, minerals, nature, nodule, nodules, sample, science, silica, silicon, specimen