Cratonic Mantle Root (IMAGE) Arizona State University Caption This is an image of a sample of cratonic mantle root from Kimberley, South Africa. The rock consists of dark green olivine, whitish-green enstatite, emerald green diopside and purple garnet. Credit Credit: David R. Bell / ASU Usage Restrictions Photographer retains all rights and permissions License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.