Variation diagrams showing components that partition into the residuum: (a) (Na₂O+CaO) and (b) (MgO + FeO_T) vs K₂O, a component that partitions into anatectic melt. Note that some leucodiatexites and leucogranites contain more K₂O than the field of anatectic melts. In (a) the AMM plots just above the pink field because its composition has been adjusted to be compatible with Archean metagreywacke (see text).