Tiger Iron
Kimberch Range, Western Australia

While there is no certainty that "Tiger Iron" is fossiliferous, many geologists believe that it is and that it formed like stromatolites. In other words, photosynthizing bacteria or algae lay down layers of oxidized heavy metals, most notably iron, during the process of their tidal deposition. The layering in "Tiger Iron" is compatible with this view, but to account for the absence of granular material, one must hypothesize that metamorphic changes have taken place as well.
Copyright © 2003 Giraud Foster & Norman Barker