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Glossary · Preservation

Concretion

A hard, rounded mass that grew in sediment by precipitation of a cementing mineral (calcite, siderite, phosphate) around a nucleus, often a fossil; the Mazon Creek siderite nodules and the Santana phosphate concretions are the classic fossil concretions.

A hard, rounded mass that grew in sediment by precipitation of a cementing mineral (calcite, siderite, phosphate) around a nucleus, often a fossil; the Mazon Creek siderite nodules and the Santana phosphate concretions are the classic fossil concretions.

Sources

Cite this article

Stratum Strata. "Concretion" (Glossary). Stratum Strata pack 2026.09, as of 2026-09-16. https://stratum.black/strata/glossary/concretion. Accessed 2026-09-21.

BibTeX · CSL-JSON

@misc{stratum-concretion,
  title        = {Concretion},
  author       = {{Stratum Strata}},
  howpublished = {\url{https://stratum.black/strata/glossary/concretion}},
  year         = {2026},
  note         = {Glossary article, Stratum Strata pack 2026.09, as of 2026-09-16; sources: stratum. Accessed 2026-09-21.}
}

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