COMPOSITION OF GARNETS WITH DIAMOND INCLU SIONS FROM KRASNOPRESNENSKAYA KEMBERLITE PIPE (YAKUTIA)

Three diamondiferous garnets from the Krasnopresnenskaya kimberlite pi pe have been studied. Compositionally, they belong to the harzburgite- dunite ultrabasic diamond paragenesis. As distinct from the garnet inc lusions in diamonds from the same pipe, the garnets containing diamond inclusions are characterized by higher chromium and lower alumina con tents. Also, the composition of a secondary material has been studied that fills fractures in the diamondiferous garnets. A symmetrical-zone d distribution of elements such as Si, Cr, Al and K has been found. Co mparison of compositions and products of secondary alteration of diamo ndiferous garnets from different kimberlite pipes in Yakutia and South Africa indicates that these minerals have specific features in each p articular kimberlite pipe.