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Related to plagioclase: Potassium feldspar, pyroxene, biotite


(Minerals) a series of feldspar minerals consisting of a mixture of sodium and calcium aluminium silicates in triclinic crystalline form: includes albite, oligoclase, and labradorite
plagioclastic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈpleɪ dʒi əˌkleɪs)

any of the feldspar minerals varying in composition from albite, NaAlSi3O8, to anorthite, CaAl2Si2O8.
pla`gi•o•clas′tic (-ˈklæs tɪk) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


Any of a series of common feldspar minerals, consisting of mixtures of sodium and calcium aluminum silicates. Plagioclase is typically white, yellow, or reddish-gray, but it can also be blue to black. It is especially common in igneous rocks.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.plagioclase - any of a series of triclinic feldspars that form rocks
dacite - a grey volcanic rock containing plagioclase and quartz and other crystalline minerals
basalt - the commonest type of solidified lava; a dense dark grey fine-grained igneous rock that is composed chiefly of plagioclase feldspar and pyroxene
feldspar, felspar - any of a group of hard crystalline minerals that consist of aluminum silicates of potassium or sodium or calcium or barium
albite, white feldspar - a widely distributed feldspar that forms rocks
anorthite - rare plagioclastic feldspar occurring in many igneous rocks
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
GreenSpar is a form of the mineral Anorthosite (aluminosilicate), a rare compositional variety of plagioclase feldspar.
The granite in the complex is mainly composed of alkali feldspar, quartz, Plagioclase, muscovite and biotite.
Biotite extracted from various depths yielded an age of 1600 to 3130 Ma, plagioclase -920 to 2100 Ma, microcline and amphibole 460-1960 Ma.
Diogenites, which formed in magma chambers deep in Vesta's crust, are composed mostly of orthopyroxene and hypersthene, with smaller amounts of olivine, plagioclase, troilite, and chromite.
Concentrations of CaO and [Na.sub.2]O in both areas can mean reflection of altered calco-sodium plagioclase that is represented by clay in this region.
In situ [sup.87]Sr/[sup.86]Sr analysis is presented in three case studies which deal with the following: (i) plagioclase crystals from Nisyros volcano (Greece), (ii) glassy matrix of single glassy clasts from the 2010 eruption of the Eyjafjallajokull volcano (Iceland), and (iii) bones and teeth from fossil remains of the Ursus spelaeus.
From XRD analysis, the rock samples were composed of predominantly silicate minerals (44.6% quartz, 26.4% plagioclase, and 19.6% K-feldspar) and clay minerals (4.8% chlorite, 4.3% illite, and 0.3% kaolinite) (Table 1).
This mineral - plagioclase - is the primary mineral found in Moon's crust.
As expected from the literature (GILL, 2015), plagioclase was the most abundant (greatest peak in Figure 1) and among the most soluble minerals in the RM (RAMOS et al., 2015).