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Title: Comment on “Discovery of davemaoite, CaSiO 3 -perovskite, as a mineral from the lower mantle”
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 CaSiO 3 stoichiometry and is equally consistent with inclusions observed in other lithospheric diamonds.  more » « less
Award ID(s):
2025779
PAR ID:
10336507
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Science
Volume:
376
Issue:
6593
ISSN:
0036-8075
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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