Re-Os dating of sulphide inclusions zonally distributed in single Yakutian diamonds: Evidence for multiple episodes of Proterozoic formation and protracted timescales of diamond growth

The very radiogenic initial Os isotope ratios of the eclogitic and lherzolitic sulphides (187Os/188Os = 0.14-2.22) imply incorporation of radiogenic Os from subducted oceanic lithosphere, a conclusion that is also supported by the anomalously light carbon isotope compositions of some diamonds. Subducted lithosphere is therefore considered a significant component in Proterozoic diamond formation beneath the Siberian Craton.