natrolite

natrolite
/na"treuh luyt', nay"-/, n.
a white or colorless zeolite mineral, a hydrous silicate of sodium and aluminum, Na2Al2Si3O10·2H2O, often occurring in acicular crystals.
[1795-1805; NATRO(N) + -LITE]

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      hydrated sodium aluminosilicate mineral, Na2Al2Si3O10·2H2O, in the zeolite family. It has been found in the form of colourless or white, glassy, slender crystals or fibrous masses filling cavities or fissures in basaltic rocks, as in Trentino, Italy; Brevik, Nor.; Belfast, N.Ire.; the Faroe Islands; and northeastern New Jersey, U.S. Natrolite was one of the first zeolite minerals for which cation-exchange properties (dissolved sodium, potassium, calcium, and magnesium readily replacing one another in the molecular structure) were discovered. It is used in softening water.

      Natrolite is the principal member of a group of zeolite minerals whose molecular structure is predominantly chains of linked silicate and aluminate tetrahedra (four oxygen atoms arranged at the points of a triangular pyramid about a central silicon or aluminum atom); the relative scarcity of lateral bonds between chains results in the characteristic fibrous appearance of the group. Other zeolites in the natrolite group are mesolite, scolecite, thomsonite, and gonnardite; all have similar modes of occurrence, molecular structures, and physical properties, even though they have different crystal symmetries: mesolite and scolecite crystallize in the monoclinic system (three unequal axes with one inclined to the plane of the other two), whereas natrolite, thomsonite, and gonnardite crystallize in the orthorhombic system (three unequal axes at right angles to one another). Mesolite is chemically intermediate between natrolite and scolecite. For chemical formulas and detailed physical properties, see zeolite (table).

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Universalium. 2010.

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Look at other dictionaries:

  • Natrolite — Catégorie IX : silicates[1] Natrolite Nasik District, Maharashtra, Inde (11x9x7 cm) …   Wikipédia en Français

  • Natrolite — General Category Tectosilicate Chemical formula Na2Al …   Wikipedia

  • NATROLITE — Parmi les zéolites fibreuses, la natrolite (du grec natron , soude, et lithos , pierre) est la plus fréquente. C’est un tectosilicate, dans lequel une partie de la silice est remplacée par de l’alumine. La formule chimique théorique s’écrit… …   Encyclopédie Universelle

  • Natrolite — Na tro*lite (?; 277), n. [Natron + lite: cf. F. natrolithe.] (Min.) A zeolite occuring in groups of glassy acicular crystals, and in masses which often have a radiated structure. It is a hydrous silicate of alumina and soda. [1913 Webster] …   The Collaborative International Dictionary of English

  • natrolite — [na′trə līt΄, nā′trəlīt΄] n. [Ger natrolith < natron (< Fr: see NATRON) + lith, LITE] a hard, light colored, orthorhombic zeolite, Na2Al2Si3O10·2H2O, characterized by crystals that radiate out, often needlelike, from a central point;… …   English World dictionary

  • natrolite — natrolitas statusas T sritis chemija apibrėžtis Ceolitas, mineralas. formulė Na₂[Al₂Si₃O₁₀]·2H₂O atitikmenys: angl. natrolite rus. натролит …   Chemijos terminų aiškinamasis žodynas

  • natrolite — noun Etymology: German Natrolith, from Natron (from French) + lith lite Date: circa 1805 a hydrous silicate of sodium and aluminum that is related to zeolite …   New Collegiate Dictionary

  • natrolite — noun A fibrous zeolite mineral, being a sodium aluminosilicate, of the chemical formula NaAlSiO middot;2HO …   Wiktionary

  • natrolite — na·tro·lì·te s.f. TS mineral. minerale costituito da alluminosilicato di sodio idrato appartenente al gruppo delle zeoliti, che cristallizza nel sistema rombico {{line}} {{/line}} DATA: 1834. ETIMO: comp. di natro e 1 lite …   Dizionario italiano

  • natrolite — na·tro·lite …   English syllables

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