In fact, to perform any type of quantitative modelling of the system, the composition of the parental magma Rotenone required. This is notoriously challenging to obtain—in the Bushveld Complex, for example, the nature of the parental magma(s) has been hotly debated for decades without complete consensus (Wilson, 2012). In some cases, parental magma compositions may be approximated from appropriate fine-grained rocks associated with the intrusion in question (chilled margins or feeder dykes or sills). However, there is no fine-grained material in the Doros suite dihybrid cross may be considered equivalent to a parental liquid. As is evident from its evolved and intensely altered chemistry, the chilled margin is not a suitable candidate, contrary to the interpretation of Hodgson and Botha (1974). The chilled gabbroic sill has approximately cotectic normative mineral proportions but has also been affected by alteration to some extent. In any case, there is no assurance that a dyke or chilled phase is representative of the parental magma for an intrusion as a whole (Godel et al., 2011 and Wilson, 2012).
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