Diamonds calcite inclusions

Carbonate has been observed infrequently as inclusions in diamond. Calcite was described by Meyer and McCallum (1986) and Brenker et al. (2002), magnesite by A. Wang et al. (1996), and dolomite by Stachel et al. (1998). Of the three, the magnesite is least surprising, in that magnesite is the carbonate that is stable in peridotitic assemblages in the diamond stability field. 

Meyer and McCallum (1986) concluded that the calcite in diamonds from the Sloan kimberlites was epigenetic, not primary, in origin. Brenker et al. (2002) found CaC03 as submicron precipitates in olivine in a multiphase inclusion from Kankan, Guinea. Their interpretation was that... 

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