View source for Latite

{{Short description|Type of volcanic rock}} 
{{Infobox rock
|name=Latite
|type=Volcanic
|image=Latit - Boxberg, Hocheifel.jpg
|image caption= Latite from Boxberg, High-Eifel, Germany
}}
[[Image:Latite nicol parallei.jpg|thumb|[[Photomicrograph]] of [[thin section]] of latite (in plane [[Polarization (waves)|polarised]] light)]]
[[Image:Latite nicol incrociati.gif|thumb|[[Photomicrograph]] of [[thin section]] of latite (in cross [[Polarization (waves)|polarised]] light)]]
'''Latite''' is an [[igneous rock|igneous]], [[volcanic rock]], with [[aphanitic]]-[[Phenocryst#Classification by phenocryst|aphyric]] to aphyric-[[porphyritic]] texture. It is the volcanic equivalent of [[monzonite]]. Its [[mineral]] assemblage is usually alkali [[feldspar]] and [[plagioclase]] in approximately equal amounts. [[Quartz]] is less than five percent and is absent in a [[feldspathoid]]-bearing latite, and [[olivine]] is absent in a [[quartz]]-bearing latite. When quartz content is greater than five percent the rock is classified as [[quartz latite]].<ref name=IUGS>[http://geology.csupomona.edu/alert/igneous/igclass.htm Classification of Igneous Rocks] {{webarchive|url=https://web.archive.org/web/20110930102012/http://geology.csupomona.edu/alert/igneous/igclass.htm |date=2011-09-30 }}</ref> [[Biotite]], [[hornblende]], [[pyroxene]] and scarce [[olivine]] or [[quartz]] are common accessory minerals. Feldspathoid-bearing latite is sometimes referred to as '''tristanite.'''<ref name="philpotts-ague-2009-140-141">{{cite book |last1=Philpotts |first1=Anthony R. |last2=Ague |first2=Jay J. |title=Principles of igneous and metamorphic petrology |date=2009 |publisher=Cambridge University Press |isbn=9780521880060 |edition=2nd |page=140-141}}</ref>

[[Rhomb porphyry|Rhomb porphyries]] are an unusual variety with gray-white [[porphyritic]], [[Rhombus|rhomb]]-shaped [[phenocryst]]s embedded in a very fine grained red-brown [[Matrix (geology)|matrix]].  The composition of rhomb porphyry places it in the [[trachyte]] - latite classification of the [[QAPF diagram]].

Latite is found, for example, as lavas in Bulgaria<ref>{{cite journal | url=http://adsabs.harvard.edu/full/2001CRABS..54c..63G | title=Volcanism in the Momchilgrad Volcanotectonic Depression |author1=Georgiev, V.  |author2=Milovanov, P. | journal=Comptes rendus de l'Académie bulgare des Sciences | year=2001 | volume=54 | issue=3 | pages=63–66 | bibcode=2001CRABS..54c..63G}} Retrieved on 5 July 2015.</ref> and as [[Intrusion|intrusive]] [[laccolith]]s and [[Sill (geology)|sills]] in [[South Dakota]], US.<ref>{{cite web | url=https://mrdata.usgs.gov/geology/state/sgmc-unit.php?unit=SDTl%3B0 | title=Latitic Intrusive Rocks | publisher=[[USGS]] | accessdate=5 July 2015}}</ref>

==See also==
* [[Benmoreite]]
* [[List of rock types]]
* [[Porphyry (geology)|Porphyry]]

==References==
{{Reflist}}

{{Volcanoes}}
{{Rock type}}

{{Volcanology-stub}}
{{Igneous-rock-stub}}

[[Category:Volcanic rocks]]
[[Category:Subvolcanic rocks]]