The term charnockite in this sense is consequently not the name of a rock, but of an assemblage of rock types. The assemblage is connected by origin, the differentiation of the same parent magma. The banded structure which these rocks commonly present in the field is only in a small measure due to plastic deformation, but is to a large extent original, and has been produced by flow in a viscous crystallizing intrusive magma, together with differentiation or segregation of the mass into bands of different chemical and mineralogical composition. There have also been, of course, earth movements acting on the solid rock at a later time and injection of dikes both parallel to and across the primary foliation.