2,500 mya: Banded iron formations Banded iron formations (BIFs ... we know there was plenty of iron in Precambrian waters. Iron normally stays dissolved in seawater; it falls out of solution ...

At 2.5 billion years old and weighing in at 2.5 tonnes, the banded iron formation is so heavy that Museum engineers had to reinforce the floor underneath it in Hintze Hall. 'The rock tells a ...

I am a chemical sedimentologist: I study how and why chemical sediments form and lithify, with the goal of better understanding how chemical sedimentary rocks (e.g., carbonates, chert, iron formations ...