Source assemblage types for cratonic diamonds from X-ray synchrotron diffraction

• Published in: Lithos 2016-11, Vol.265, p.334-338
• Main Authors: Nestola, F., Alvaro, M., Casati, M.N., Wilhelm, H., Kleppe, A.K., Jephcoat, A.P., Domeneghetti, M.C., Harris, J.W.
• Format: Article
• Language: English
• Subjects: Clinopyroxene; Diamond; Eclogite; Peridotite; Synchrotron
• ISSN: 0024-4937; 1872-6143
• DOI: 10.1016/j.lithos.2016.07.037

Three single crystals of clinopyroxene trapped within three different gem-quality diamonds from the Udachnaya kimberlite (Siberia, Russia) were analysed in situ by single-crystal synchrotron X-ray diffraction in order to obtain information on their chemical composition and infer source assemblage type. A non-destructive approach was used with high-energy (≈60keV; λ ≈0.206Å) at I15, the extreme-conditions beamline at Diamond Light Source. A dedicated protocol was used to center the mineral inclusions located deep inside the diamonds in the X-ray beam. Our results reveal that two of the inclusions can be associated with peridotitic paragenesis whereas the third is eclogitic. This study also demonstrates that this non-destructive experimental approach is extremely efficient in evaluating the origin of minerals trapped in their diamond hosts. •In situ synchrotron single-crystal diffraction of pyroxenes included in diamonds•High-energy radiation and dedicated experimental protocol•High-quality crystal structure determination by a non-destructive technique•Evaluation of diamond and inclusion origin