DIRK WIERSMA / SCIENCE PHOTO LIBRARY DIRK WIERSMA / SCIENCE PHOTO LIBRARY
Banded iron formation. Folded layers of a banded iron formation (BIF or banded ironstone). Banded ironstone is a rock formed from alternating layers of the iron oxide mineral haematite (red) and tiger eye and jasper. At greater than 3 billion years of age these are among the oldest rocks on Earth. They were laid down in shallow seas where primitive bacteria caused iron to be oxidised and precipitated. Subsequent deep burial of the rocks, and tectonic movements, have caused the rock to alter and deform. This small sample is around 2 centimetres across. The rock has been cut open to expose the banding (strata), and also polished for display. Many BIFs come from Western Australia.
Model release not required. Property release not required.