Banded iron formations are found worldwide, in every continental shield of every continent. The oldest BIFs are associated with greenstone belts and include the BIFs of the Isua Greenstone Belt, the oldest known, which have an estimated age of 3700 to 3800 Ma. The Temagami banded iron deposits formed over a 50-million-year period, from 2736 to 2687 Ma, and reached a thickness of . Other examples of early Archean BIFs are found in the Abitibi greenstone belts, the greenstone belts of the Yilgarn and Pilbara cratons, the Baltic shield, and the cratons of the Amazon, north China, and south and west Africa.
Banded iron formations are found worldwide, in every continental shield of every continent. The oldest BIFs are associated with greenstone belts and include the BIFs of the Isua Greenstone Belt, the oldest k,nown which have an estimated age of 3700 to 3800 Ma. The Temagami banded iron deposits formed over a 50-million-year period from 2736 to 2687 Ma, and reached a thickness of . Other examples of early Archean BIFs are found in the Abitibi greenstone belts, the greenstone belts of the Yilgarn and Pilba,ra crato,ns, the Baltic shield and the cratons of the Amazon, north China, and south and west Africa.