Editing Pegmatite (section)

==Occurrence==
Notable pegmatite occurrences are found worldwide within the major [[craton]]s, and within [[greenschist]]-facies metamorphic belts. However, pegmatite localities are only well recorded when economic mineralisation is found.<ref>{{cite journal |last1=London |first1=David |title=Rare-Element Granitic Pegmatites |journal=Rare Earth and Critical Elements in Ore Deposits |date=2016 |doi=10.5382/Rev.18.08|isbn=9781629490922 }}</ref>

Pegmatites are found as irregular [[Dike (geology)|dikes]], [[sill (geology)|sills]], or [[Vein (geology)|veins]], and are most common at the margins of [[batholiths]] (great masses of intrusive igneous rock).<ref name=Jackson1997/> Most are closely related spatially and genetically to large intrusions. They may take the form of veins or dikes in the intrusion itself, but more commonly, they extend into the surrounding country rock,<ref name=KleinHurlbut1993/> especially above the intrusion.{{sfn|Philpotts|Ague|2009|p=255}}

Some pegmatites surrounded by [[metamorphic rock]] have no obvious connection to a larger intrusion. Pegmatites in low-grade metamorphic rock tend to be dominated by quartz and [[carbonate mineral]]s. Pegmatites in metamorphic rock of higher grade are dominted by [[alkali feldspar]].{{sfn|Philpotts|Ague|2009|p=255}}

Gabbroic pegmatites typically occur as lenses within bodies of gabbro or [[diabase]].<ref name=BlattTracy1980/> Nepheline syenite pegmatites are common in [[Alkaline magma series|alkaline]] igneous complexes.{{sfn|Philpotts|Ague|2009|p=255}}
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File:Pegmatite dans micaschiste.jpg|Pegmatite (light colored) in dark [[mica schist]], [[Île de Noirmoutier]], France
File:Pegmatite Formation (Isle of Skye).jpg|Pegmatite (pink), [[Isle of Skye]], Scotland
File:BlackCanyon-Pegmatites.jpg|Potassium feldspar pegmatites at the [[Black Canyon of the Gunnison National Park]], Colorado
File:Pegmatite dyke Cap-de-Creus.jpg|[[Variscan orogeny|Hercynian]] pegmatite dike intruded into [[Ediacaran]] schist, [[Cap de Creus]] peninsula, Catalonia, Spain<ref>Elena Druguet and Jordi Carreras, [https://www.semanticscholar.org/paper/Folds-and-Shear-Zones-at-Cap-de-Creus-Carreras/7976e821278454959813206aa68e8fe98893f246 ''Folds and Shear Zones at Cap de Creus''], 2019, Field Trip Guide, at semanticscholar.org.</ref>
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