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Related to anorthite: labradorite


A white to gray variety of plagioclase feldspar that contains a high proportion of calcium to sodium and occurs in alkaline igneous rocks such as gabbro and anorthosite.

[From Greek an-, not; see a-1 + orthos, straight (from its oblique crystals).]

an′or·thit′ic (-thĭt′ĭk) adj.


(Minerals) a white to greyish-white or reddish-white mineral of the feldspar group and plagioclase series, found chiefly in igneous rocks and more rarely in metamorphic rocks. It is used in the manufacture of glass and ceramics. Composition: calcium aluminium silicate. Formula: CaAl2Si2O8. Crystal structure: triclinic
[C19: from an- + ortho- + -ite1]
anorthitic adj


(ænˈɔr θaɪt)

a white or gray feldspar mineral, CaAl2Si2O8, calcic plagioclase.
[1823; an-1 + Greek orth(ós) straight + -ite1]
an`or•thit′ic (-ˈθɪt ɪk) adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.anorthite - rare plagioclastic feldspar occurring in many igneous rocksanorthite - rare plagioclastic feldspar occurring in many igneous rocks
oligoclase, plagioclase - any of a series of triclinic feldspars that form rocks
References in periodicals archive ?
The convective currents are likely to be a consequence of new injections of material that cause magmatic fractionation and ultimately changes the composition of the surrounding liquid, hence, modifying the composition of the plagioclase crystal lattices creating successive changes of the anorthite content of the plagioclase fringes.
Enst: enstatite; Qz: quartz; Mul: mullite; Cris: cristobalite; Hem: Hematite; Anor: anorthite.
The study by FARIA (2008) demonstrated that the crystal grains are richer in Na at their periphery and richer in Ca at the core, so the composition of the borders is albite (the sodic plagioclase), and the core is anorthite (the calcic plagioclase).
Y fformiwla am y ffeldspar anorthite yw CaAl2Si2O8 a chynhwysa hwn ganran uchel o galch a pherthynai i'r grwp plagioclase o ffeldspar.
Plagioclase is characterised by a strong chemical variation, with anorthite values from [An.
2], which favors the increase of the ion bicarbonate in the waters; dissolution of anorthite and K-feldspar; precipitation of albite and K-mica; a small release of methane gas; and ionic exchanges of the cations [Ca.
After the analyses, the soil minerals found were: quartz, calcite, sanidine, albite, nontronite, muscovite, montmorillonite, hematite, faujasite, dolomite, microcline, anorthite, anorthoclase, clinochlore and epidote.
Besides quartz, the most common inclusions are muscovite, anorthite and ferrosilicon.
3--Halite + Antigorite + Anorthite + Magnesite + Montmorillonite NaCl + [Mg.
The phase composition of the samples of ceramic tiles is represented mainly by quartz, anorthite and a small amount of hematite and almost the same for all investigated compositions.