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Related to felsite: Felsitic Texture


A fine-grained, light-colored igneous rock, composed chiefly of feldspar and quartz.

fel·sit′ic (-sĭt′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈfɛlsaɪt) or


(Geological Science) any fine-grained igneous rock consisting essentially of quartz and feldspar
[C18: fels(par) + -ite1]
felsitic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈfɛl saɪt)

a dense fine-grained igneous rock consisting typically of feldspar and quartz, both of which may appear as phenocrysts.
[1785–95; fels (par) + -ite1]
fel•sit•ic (fɛlˈsɪt ɪk) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
The veins occupy northwest-striking fractures that cut volcanic rocks, microdiorite and felsite porphyry of the Cretaceous-age Tip Top Hill Formation.
Carbonate-Rich Albitite and Albitite Felsite. The carbonate-rich albitite consists of fine to medium grains of near end-member albite ([Ab.sub.97-100]), calcite, and dolomite (Figure 4(d)).
The Braithwaites though-they've gotten wind of the outing and are planning to join with their little semihellions, Felsite and Fillmore.
The 16 papers here discuss such matters as the felsite quarry complex of Northmaven in Scotland, new discoveries at the Mynydd Rhiw axehead production site, seamer axeheads in southern England, obsidian in the Near East during the Halaf period as a case study on why people use exotic raw material, interpreting evidence for prehistoric conflict, and ideology and context within the European flint-mining tradition.
Rare earth element deposits in inferred felsite intrusions.
(1968) The Rooiberg Felsite north of Middelburg and its relation to the layered sequence of the Bushveld Complex.
Perhaps we should associate the appearance of the felsite bar whetstone in Period sub-III with this development of polished slate.
These intermediate-felsic hypabyssal rocks are mainly composed of quartz porphyry, granite porphyry, granite, felsite, granodiorite, quartz monzonite, and diorite porphyry.
Fletcher (1881, 1884) divided the mountain into a "central slate series" surrounded by "syenite" and "felsite", unconformably overlain by Devonian sedimentary rocks.