Long Journey (IMAGE) Columbia Climate School Caption The authors of a new paper believe that raw materials for diamonds and certain unusual oceanic islands come from the same places. From right to left: 1) ocean crust subducts into earth's mantle deep under a continent; 2) the carbon-rich crust interacts with, and alters, the continental root; 3) part of the altered root drops off and sinks to the mantle/core boundary; 4) the material is taken up in a hot plume that rises back to the surface; 5) the plume erupts from under the seabed to form islands. The scientists estimate the process might take 2.7 billion years. Credit Y. Weiss et al., Nature 2016 Usage Restrictions Credit must be given. 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.