Polycrystalline aggregates of bort-type diamond with inclusions of garnet and rutile from the Mir pipe have δ13C of –3.7 to –22.9%o PDB. The bort of variety VIII (yu. L. Orlov’s classification) differs from the bort of variety IX in having a narrower range of δ13C (–3.7 to –9.4 and –3.8 to –22.9%c, respectively). The isotopically heavy diamond aggregates δ13C ≳ 10%o) with cubic individuals make a greater contribution of 12C than the aggregates having individuals of other morphological types. Within the Mir pipe, the E-type bort is statistically enriched in 13C relative to single crystals of diamond of the same paragenesis.
You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
