banded iron formation
Definition of banded iron formation
: 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 Chang, New York Times, 2 Dec. 2008 ◆Banded iron formations, which formed over a billion years ago, are often used today as a source of low-grade iron ore. —abbreviation BIF
Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.
Join MWU now and get access to America’s largest dictionary, with:
- 300,000 words that aren't in our free dictionary
- Expanded definitions, etymologies, and usage notes
- Advanced search features
- Ad free!
First Known Use of banded iron formation
Seen and Heard
What made you want to look up banded iron formation? Please tell us where you read or heard it (including the quote, if possible).