page_title: Charnockite
section_title: Geology
hierarchical_section_title: Charnockite / Geology
caption_attribution_description: Deutsch: Incipient Charnockite, Conradgebirge, Dronning Maud Land, Antarktika.
context_page_description: Charnockite is applied to any orthopyroxene-bearing quartz-feldspar rock, formed at high temperature and pressure, commonly found in granulite facies metamorphic regions, as an end-member of the charnockite series.
context_section_description: All charnockites were once thought to be igneous, but it is now recognized that many are metamorphic, because, despite the high temperatures and pressures, the original protolith never actually melted. However, some orthopyroxene-bearing granites with distinct igneous features exist, and these rocks also fall within the definition of charnockite.
  Many of the minerals of these rocks are schillerized, as they contain minute platy or rod-shaped inclusions, disposed parallel to certain crystallographic planes or axes. The reflection of light from the surfaces of these inclusions gives the minerals often a peculiar appearance, e.g. the quartz is blue and opalescent, the feldspar has a milky shimmer like moonshine, the hypersthene has a bronzy metalloidal gleam. Very often the different rock types occur in close association as one set forms bands alternating with another set, or veins traversing it, and where one facies appears the others also usually are found.
  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.
caption: Incipient Charnockite, Dronning Maud Land, Antarctica
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