Comment on "Discovery of davemaoite, CaSiO3-perovskite, as a mineral from the lower mantle"

Michael J Walter; Simon C Kohn; D Graham Pearson; Steven B Shirey; Laura Speich; Thomas Stachel; Andrew R Thomson; Jing Yang

doi:10.1126/science.abo0882

Comment on "Discovery of davemaoite, CaSiO₃-perovskite, as a mineral from the lower mantle"

Science. 2022 May 6;376(6593):eabo0882. doi: 10.1126/science.abo0882. Epub 2022 May 6.

Authors

Michael J Walter¹, Simon C Kohn², D Graham Pearson³, Steven B Shirey¹, Laura Speich⁴, Thomas Stachel³, Andrew R Thomson⁵, Jing Yang¹

Affiliations

¹ Earth and Planets Laboratory, Carnegie Institution for Science, Washington, DC 20015, USA.
² School of Earth Sciences, University of Bristol, Bristol BS8 1TL, UK.
³ Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada.
⁴ Swiss Gemmological Institute SSEF, CH-4051 Basel, Switzerland.
⁵ Department of Earth Sciences, University College London, London WC1E 6BT, UK.

PMID: 35536897
DOI: 10.1126/science.abo0882

Abstract

Tschauner et al. (Reports, 11 November 2021, p. 891) present evidence that diamond GRR-1507 formed in the lower mantle. Instead, the data support a much shallower origin in cold, subcratonic lithospheric mantle. X-ray diffraction data are well matched to phases common in microinclusion-bearing lithospheric diamonds. The calculated bulk inclusion composition is too imprecise to uniquely confirm CaSiO₃ stoichiometry and is equally consistent with inclusions observed in other lithospheric diamonds.

Publication types

Comment