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.