Abstract: Minerals from the deep mantle may have recorded the formation history and evolution of the Earth in early times. Investigating the composition of different types of matter deep inside the Earth and the physical and chemical environment during their formation is a subject at the forefront of the Earth sciences. The synchrotron-based energy－dispersive X－ray diffraction method has great advantage and potential for diagnosing the crystal structure of tiny minerals and mineral inclusions. The synchrotron Beamline X17C at Brookhaven National Laboratory in New York has been used to analyze deep mantle minerals from Tibet and samples from Chinese Continental Scientific Drilling (CCSD) cores. Some new mineral species and unusual crystal features have been identified, barringerite (Fe2P alloy) from a CCSD core sample and a Tibetan diamond of unusual structure being two such examples