Abstract
Sun et al. (2017) reported petrographic, chemical and Os isotope data on eleven mantle xenoliths from the Obnazhennaya kimberlite and claimed that their results enable them to establish “the character of the lithospheric mantle beneath the northern Siberian craton”.1 Here we show that their results are neither novel nor pertinent, and that errors in data treatment and interpretations discredit many of their conclusions.