AbstractA major element of variability of olivine melt inclusions in Mauna Loa lavas is here proved to be strictly related to olivine crystallization at inclusion walls, at low pressure and decreasing temperature.In so doing it is probably worth it to interpret trace elements and isotope variability in these olivine trapped liquids as the effect of disequilibrium (isotope) fractionation. In this respect, the accurate analytical work performed by Sobolev et al. (2011) does not document the presence of a heterogeneous source, rather representing a tool to explore poorly documented aspects of magmatic crystallization that are controlled by the kinetics of liquid-solid phase transition.