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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


(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.


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.
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
References in periodicals archive ?
Basalt fibres are the fibres made of extremely fine fibres of basalt, comprising the minerals pyroxene, plagioclase and olivine, having better physicomechanical properties than fiberglass, and significantly economical than carbon fibre.
Specifically, they are located within the Scrag Lake biotite monzogranite pluton in which quartz, K-feldspar, plagioclase, and biotite are the major mineral constituents (MacDonald 2001).
In general, the ceramic cross-sections showed dominant quartz, plagioclase and K-feldspars that were uniformly distributed throughout the ceramic fabric and often had a bimodal grain-size (typically < 50 [micro]m and 100-300 [micro]m), which together with the occurrence of angularly shaped larger grains suggest excessive tempering.
Most Quebrada de Humahuaca fabrics, from Coctaca, Pucara de Tilcara, Pucara de Perchel and Esquina de Huajra, were very similar, comprising 20-30 per cent generally rounded altered pelites, rare sandstone grains, abundant quartz and rounded plagioclase (Figure 6a).
The Oro sites were in a flat landscape with Vitrand (Soil Survey Staff 2014) soils formed in aliuvially redeposited tephra, having mineralogy dominated by plagioclase, with smectite as a minor component.
In the ZMT--336 samples that is harvested from Zone Skarn are mineral garnet, plagioclase, epidote along with diopcide in the background of rock in the strip form of diopcide and epidote minerals.
Basalt fiber is a material made from extremely fine fibers of basalt, which is composed of the minerals plagioclase, pyroxene and olivine.
Although it was not specifically observed, it is inferred to be a fault contact due to the presence of mylonitic foliation (N10[degrees]E/90[degrees]), which is defined by quartz and plagioclase porphyroclasts in the hornblende schists (Figure 2d).
In its thin sections, the rock has a hypo-crystalline matrix which is composed of porphyritic texture and is rich in a sprinkled opaque mineral, plagioclase, feldspathoid mineral and obsidian.
But it's got more plagioclase (an aluminum containing mineral) than they're seeing on the surface of Mercury and it plots funny in 'oxygen isotope space.
First, according to the mineralogical composition of basalt are represented mainly plagioclase and clinopyroxene, which total content is 70-85%.