BY ROGER N. SCOON AND ANDREW A. MITCHELL.
Günther et al. (2018) have either overlooked or misunderstood the complexities of the platiniferous dunite pipes of the Bushveld Complex, South Africa in many respects. The attempt to suggest there is a continuum of olivine compositions between the main bodies of dunite and the outer envelopes and core-zones is baffling: the pipes are comprised of discrete petrological assemblages (Scoon and Mitchell, 2004a; Wagner, 1929). The complexity of the semi-concentric zonation, over and above the occurrence of the PGE-rich core-zones formed the basis for Viljoen and Scoon (1985) categorizing these features as a specialized category of discordant ultramafic body.