The Dynamic Earth View Multimedia Version

Main Menu >  GeoGallery >  Rocks >  Chert
TITLE: GeoGallery

Choose one of the following Rocks for more details:

Banded Iron Formation

Banded Iron Formation

The layers of red chert and gray, iron-rich hematite record seasonal changes in ocean waters. The iron oxide precipitated when warm, oxygen-bearing water from the surface mixed with cold, iron-rich water beneath it.


bottom navigation bar Smithsonian National Museum of Natural History Department of Mineral Sciences website Credits