Composition of the crystallizing phase during magma ocean crystallization, in terms of minerals Mg/Fe-bridgmanite, Mg/Fe-ferropericlase, and stishovite, as a function of pressure (GPa). The depth of the mantle extends from the surface (0 GPa), to the core–mantle boundary (138 GPa, 2891 km). Cumulates are re-homogenized at pressures of 0–25 GPa (indicated by a black line) and, therefore, demonstrate constant composition (see Sect. 2.2). Compositions are 8 wt% FeO (Earth-like) and Mg/Si is annotated.