Editing Eclogite (section)

=== Classification ===
Eclogites are defined as bi-mineralic, broadly basaltic rocks which have been classified into Groups A, B and C based on the chemistry of their primary mineral phases, garnet and clinopyroxene.<ref name=":13">{{Cite journal|last=Jacob|first=D. E.|date=2004-09-01|title=Nature and origin of eclogite xenoliths from kimberlites|url=https://www.sciencedirect.com/science/article/pii/S0024493704001045|journal=Lithos|series=Selected Papers from the Eighth International Kimberlite Conference. Volume 2: The J. Barry Hawthorne Volume|language=en|volume=77|issue=1|pages=295–316|doi=10.1016/j.lithos.2004.03.038|issn=0024-4937|url-access=subscription}}</ref><ref name=":0">{{Cite journal|last1=COLEMAN|first1=R. G|last2=LEE|first2=D. E|last3=BEATTY|first3=L. B|last4=BRANNOCK|first4=W. W|date=1965-05-01|title=Eclogites and Eclogites: Their Differences and Similarities|url=https://doi.org/10.1130/0016-7606(1965)76[483:EAETDA]2.0.CO;2|journal=GSA Bulletin|volume=76|issue=5|pages=483–508|doi=10.1130/0016-7606(1965)76[483:EAETDA]2.0.CO;2|issn=0016-7606|url-access=subscription}}</ref> The classification distinguishes each group based on the jadeite content of clinopyroxene and pyrope in garnet.<ref name=":0" /> The rocks are gradationally less mafic (as defined by SiO<sub>2</sub> and MgO) from group A to C, where the least mafic Group C contains higher [[Alkaline earth metal|alkali]] contents.<ref name=":02">{{Cite journal|last1=COLEMAN|first1=R. G|last2=LEE|first2=D. E|last3=BEATTY|first3=L. B|last4=BRANNOCK|first4=W. W|date=1965-05-01|title=Eclogites and Eclogites: Their Differences and Similarities|url=https://doi.org/10.1130/0016-7606(1965)76[483:EAETDA]2.0.CO;2|journal=GSA Bulletin|volume=76|issue=5|pages=483–508|doi=10.1130/0016-7606(1965)76[483:EAETDA]2.0.CO;2|issn=0016-7606|access-date=2021-11-30|archive-date=2022-02-12|archive-url=https://web.archive.org/web/20220212025752/https://pubs.geoscienceworld.org/gsa/gsabulletin/article-abstract/76/5/483/5909/Eclogites-and-Eclogites-Their-Differences-and?redirectedFrom=fulltext|url-status=live|url-access=subscription}}</ref>

The transitional nature between groups A, B and C correlates with their mode of emplacement at the surface.<ref name=":0" /> Group A derive from [[craton]]ic regions of Earth's crust, brought to the surface as xenoliths from depths greater than 150&nbsp;km during [[kimberlite]] eruptions.<ref name=":13"/><ref name=":0" /> Group B show strong compositional overlap with Group A, but  are found as lenses or pods surrounded by [[Peridotite|peridotitic]] mantle material.<ref name=":0" /> Group C are commonly found between layers of [[mica]] or [[Glaucophane Schist Facies|glaucophane schist]], primarily exemplified by the New Caledonia tectonic block and off the coast of California.<ref name=":03">{{Cite journal|last1=COLEMAN|first1=R. G|last2=LEE|first2=D. E|last3=BEATTY|first3=L. B|last4=BRANNOCK|first4=W. W|date=1965-05-01|title=Eclogites and Eclogites: Their Differences and Similarities|url=https://doi.org/10.1130/0016-7606(1965)76[483:EAETDA]2.0.CO;2|journal=GSA Bulletin|volume=76|issue=5|pages=483–508|doi=10.1130/0016-7606(1965)76[483:EAETDA]2.0.CO;2|issn=0016-7606|access-date=2021-11-30|archive-date=2022-02-12|archive-url=https://web.archive.org/web/20220212025750/https://pubs.geoscienceworld.org/gsa/gsabulletin/article-abstract/76/5/483/5909/Eclogites-and-Eclogites-Their-Differences-and?redirectedFrom=fulltext|url-status=live|url-access=subscription}}</ref>