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Any of various faintly foliated, nearly massive varieties of quartzofeldspathic rocks containing hypersthene.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(named for the founder of Calcutta, J. Charnock), a hypersthene granite typical of Precambrian assemblages that contain migmatites. Charnockite is composed of orthoclase, oligoclase, quartz, and hypersthene; it also often includes the garnets almandine and pyrope, as well as biotite, magnetite, and other minerals. Two types of charnockites are distinguished: ferrohypersthene charnockite and garnet charnockite.

The composition of charnockite varies. It is currently believed that ferrohypersthene charnockites occur in relatively shallow fades, whereas garnet charnockites are typical of more deep-seated metamorphic facies. The formation of garnet charnockites whose outcroppings are observed in the most deeply eroded Precambrian shields (Indian, Sinian, Aldan, Baltic, and Canadian), is distinguished. The origin of charnockites is linked with magmatism and metamorphism; charnockites are associated with anorthosites and other plutonic rocks, forming the charnockite-anorthosite series.

The term “charnockite” was first proposed by the British geologist T. Holland in 1900 for the intrusive rocks of the Madras area, which contain ferruginous hypersthene as the chief mineral.


Winkler, H. Genezis metamorficheskikh porod. Moscow, 1969.
Charnockites. New Delhi, 1964. (International Geological Congress: Report of the Twenty-second Session. India, 1964, part 13.)


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Melzer, "Experimental partitioning of Rb and K between phlogopite and a concentrated (K,Rb)Cl brine: Implications for the role of concentrated KCl brines in the depletion of Rb in phlogopite and the stability of phlogopite during charnockite genesis," Lithos, vol.
2008), this region is occupied by the large Kursiai batholith with a few minor plutons made up of a suite of dominantly charnockitic granitoid rocks (mangerite, enderbite, opdalite, charnockite and granite).
Geology Rank Weight Total weight Charnockite Group 6 4 24 Gneiss 6 4 24 Ultrabasic rocks 6 3 18 (a) Geology Weight.
Almost all commercial bauxite has Alkali Feldspar Charnockite (AFCh) content 50-55% [8].
Other secondary rocks used in delineating them are carbonates, calc gneiss and banded iron formation (BIF) and Older granites, which include granite, granodiorite, diorite charnockite, pegmatites and aplites.
The basement complex of Southwestern Nigeria predominantly composed of migmatite and granitic gneiss; quartzite; slightly migmatised to unmigmatised metasedimentary schist and metaigneous rocks; charnockite; gabbro and diorite; and the members of the older granite suite, mainly granites, granodiorites, and syenites.
Prominent rock units include granite gneiss, migmatites, schist/ quartz schist, porphyritic granite, fine-medium grained granite and charnockite.
Among the Lankan granite varieties popular are Dolorite, Charnockite, Gneiss Granite, Pink Granite, Rose Quartz, and Calcite.
The important rock types encountered in this area are Granitic gneiss, Mica Gneiss, Hornblende Gneiss, Charnockite and pink Granite.