closed system differentiation of the ferro-basaltic magma. Skaergraad's differentiation trend has also figured prominently in the so-called "granite controversy" as to how granites arise as it thought to refute the idea that granites are differentiation products of basaltic magmas (but see a reversal to this idea by Hunter ans Sparks, 1987, who claimed that Skaergaard had indeed produced copius quantites of granitic material).