lustre

lustre
/lus"teuhr/, n., v.t., v.i., lustred, lustring. Chiefly Brit.
luster.

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In mineralogy, the appearance of a mineral surface in terms of its light-reflecting qualities.

Lustre depends on a mineral's refractivity (see refraction), transparency, and structure. Variations in these properties produce different kinds of lustre, from metallic (e.g., gold) to dull (e.g., chalk).

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      in mineralogy, the appearance of a mineral surface in terms of its light-reflective qualities. Lustre depends upon a mineral's refractive power, diaphaneity (degree of transparency), and structure. Variations in these properties produce different kinds of lustre, whereas variations in the quantity of reflected light produce different intensities of the same lustre. The kind and intensity of lustre is the same for crystal faces of like symmetry but may be different on those with different symmetry.

      The kinds of lustre are usually described as follows (the prefix “sub-,” as in submetallic, is used to express imperfect lustre of the kind): metallic (the lustre of metals—e.g., gold, tin, copper; minerals with a metallic lustre are usually opaque and have refractive indices near 2.5); adamantine (nearly metallic lustre of diamond and other transparent or translucent minerals with high refractive indices [between 1.9 and 2.5] and relatively great density—e.g., cerussite and other compounds of lead); vitreous (the lustre of broken glass—the most common lustre in the mineral kingdom; it occurs in translucent and transparent minerals with refractive indices between 1.3 and 1.8, as in quartz); resinous (the lustre of yellow resins—e.g., sphalerite); greasy (the lustre of oiled surfaces—e.g., nepheline, cerargyrite); pearly (like pearl or mother-of-pearl—e.g., talc; surfaces parallel to a perfect cleavage exhibit this lustre, which results from the repeated reflections from minute cleavage cracks); silky (like silk—e.g., satin spar; minerals with a fibrous structure have this lustre); dull, or earthy (without lustre—e.g., chalk).

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Universalium. 2010.

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  • lustre — 1. (lu str ) s. m. 1°   Le brillant et le poli que l on donne à un objet ou qu un objet a naturellement. •   Une perle.... D assez de lustre, pour être La marque d un si beau jour, MALH. II, 5. •   Sublimé et esprit de vin, pour donner le bel… …   Dictionnaire de la Langue Française d'Émile Littré

  • lustre — LUSTRE. s. m. L Eclat de quelque chose de poli, de luisant, de lissé & d uni. Le lustre d une estoffe. cette estoffe n a point de lustre, a perdu son lustre. il a bien du lustre. l ebene bien polie a un grand lustre. le verni de la Chine est d un …   Dictionnaire de l'Académie française

  • lustré — lustré, ée (lu stré, strée) part. passé de lustrer. 1°   Qui a passé par le lustre. Étoffe lustrée.    Percale lustrée, percale qui a reçu un apprêt qui la rend luisante et ferme.    Par extension. •   En classe, un banc de chêne, usé, lustré,… …   Dictionnaire de la Langue Française d'Émile Littré

  • Lustre — or Luster may refer to:* Luster, Norway, a community in Norway * Lustre (mineralogy), a description of the way light interacts with the surface of a crystal, rock, or mineral * Luster, a description of the way light interacts with the surface of… …   Wikipedia

  • lustre — sustantivo masculino 1. (no contable) Brillo de las superficies: El lustre de sus zapatos llama la atención. El lustre de tu pelo es estupendo. 2. (no contable) Prestigio o distinción de las personas: Su presencia da siempre lustre a cualquiera… …   Diccionario Salamanca de la Lengua Española

  • Lustre — kann sein eine Programmiersprache, Lustre (Programmiersprache) Lustre (Dateisystem), ein Cluster Dateisystem Lustre (Montana), Ort in den Vereinigten Staaten Diese Seite ist eine Begriffsklärung zur Unterscheidung me …   Deutsch Wikipedia

  • lustre — Lustre, Chose qui a beau lustre, Videtur duci ab Illustris. Donner lustre à quelque chose, id est, couleur, Donner lustre, à son dire …   Thresor de la langue françoyse

  • Lustre — Lustre, ein englisches geköpertes Zeug mit glänzender Appretur, dessen Kette aus Baumwollengarn, und zwar meist von einer dunklern Farbe, als der Einschuß von Schafwolle, besteht, wodurch es die schillernde, changirende Farbe erhält. Daß ein… …   Damen Conversations Lexikon

  • lustre — (De lustrar). 1. m. Brillo de las cosas tersas o bruñidas. 2. Esplendor, gloria. ☛ V. azúcar de lustre …   Diccionario de la lengua española

  • Lustre — Lus tre, n. Same as {Luster}. [1913 Webster] …   The Collaborative International Dictionary of English

  • Lustre — (fr., spr. Lüster), 1) das feinste Schmelzglas; 2) eleganter Kronleuchter; 3) englisch geköpertes Zeug, aus Baumwollengarn, mit Einschuß von Schafwolle, meist von dunkler Farbe, hat glänzende Appretur u. schillert; 4) Garn aus der groben, langen… …   Pierer's Universal-Lexikon

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