How Much Carbon Is in the Core? (IMAGE) Carnegie Institution for Science Caption The team's experiments compared carbon's compatibility with the silicates that comprise the Earth's mantle (outer circle) to its compatibility with the iron that comprises the planet's core (inner circle) while under conditions mimicking the Earth's interior during its formative period. They found that more carbon would have stayed in the mantle than previously thought. Credit Rebecca Fischer, Elizabeth Cottrell and Marion Le Voyer, Kanani Lee, and the late Erik Hauri. Usage Restrictions With credit 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.