An innovative X-ray method enables new high-pressure investigations of samples under deep mantle conditions. The technique, which was developed by a team led by Georg Spiekermann from DESY, the German Research Centre for Geosciences GFZ and the University of Potsdam, extends the range of instruments available to high-pressure researchers. Successful tests of the new method at DESY’s X-ray light source PETRA III support the idea that heavy elements have to accumulate in magmas so that they could be stable at depths of Earth’s lower mantle. The scientists present their work in the journal Physical Review X.