banded iron formation

noun

Definition of banded iron formation

geology
:a sedimentary deposit that consists of alternating thin layers of iron oxides (such as magnetite or hematite) and iron-poor minerals (such as shale or chert)
  • That bedrock includes intriguing structures known as banded iron formations, which are believed to occur only with the help of living organisms.
  • —Kenneth ChangNew York Times2 Dec. 2008
Note: Banded iron formations, which formed over a billion years ago, are often used today as a source of low-grade iron ore.
abbreviation BIF

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First Known Use of banded iron formation

1903


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