Evidence for two blue (type IIb) diamond populations

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Fig. 1: Size-class distribution of the different inclusion associations in the blue diamonds documented by Smith et al.1 (see text for discussion).
Fig. 2: Comparison of carbon-isotopic signatures of Type IIa (CLIPPIR5) and blue IIb diamonds from Cullinan-documented10 and type IIb stones of the Ca- and Mg-associations respectively, documented by Smith et al.1.

Data availability

All data are from Smith et al.1 and cited sources.


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We thank T. Stachel for constructive comments. We thank S. Abraham for producing the figures.

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The authors collaborated closely in the formulation and writing of this manuscript.

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Correspondence to Andy E. Moore.

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Moore, A.E., Helmstaedt, H. Evidence for two blue (type IIb) diamond populations. Nature 570, E26–E27 (2019). https://doi.org/10.1038/s41586-019-1245-9

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