Sand

Sand
/sand/; Fr. /sahonnd/, n.
George /jawrj/; Fr. /zhawrddzh/ (Lucile Aurore Dupin Dudevant), 1804-76, French novelist.

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I
Mineral, rock, or soil particles that are 0.

0008–0.08 in. (0.02–2 mm) in diameter. Most rock-forming minerals are found in sand, but quartz is by far the most common. Most sands also contain a small quantity of feldspar, as well as white mica. All sands contain small quantities of heavy rock-forming minerals, including garnet, tourmaline, zircon, rutile, topaz, pyroxenes, and amphiboles. In the pottery and glassmaking industries very pure quartz sands are used as a source of silica. Similar sands are used for lining the hearths of steel furnaces. Molds used in foundries for casting metal are made of sand with a clay binder. Quartz and garnet sands are used extensively as abrasives. Among ordinary sand's many uses, it is a basic ingredient of mortar, cement, and concrete. See also tar sand.
II
(as used in expressions)
Sand George
bituminous sand

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      mineral, rock, or soil particles that range in diameter from 0.02 to 2 millimetres (0.0008–0.08 inch). Most of the rock-forming minerals that occur on the Earth's surface are found in sand, but only a limited number are common in this form. Although in some localities feldspar, calcareous material, iron ores, and volcanic glass are dominant constituents of sand, quartz is by far the commonest, for several reasons: it is abundant in rocks, is comparatively hard, has practically no cleavage so that it is not readily worn down, is nearly insoluble in water, and does not decompose. Most quartzose sands contain a small quantity of feldspar, as well as small plates of white mica, which, though soft, decompose slowly.

      All sands contain small quantities of heavy rock-forming minerals, including garnet, tourmaline, zircon, rutile, topaz, pyroxenes, and amphiboles. In some shore and river sands these heavier constituents, as well as some of the heavy native elements, become concentrated as a result of sorting by currents and the removal of the lighter constituents. Such placer sands may be economically valuable deposits worked for diamonds and other gemstones, gold, platinum, tin, monazite, and other ores. Greensands, widely distributed over the floor of the ocean and found in ancient strata on the continents, owe their colour to the presence of glauconite, a potash-bearing mineral; these sands are used for water softeners.

      In the pottery and glassmaking industries very pure quartzose sands are used as a source of silica. Similar sands are required for lining the hearths of acid-steel furnaces. Molds used in foundries for casting metal are made of sand with a clay binder. Quartz and garnet sands are used extensively as abrasives. Ordinary sands find a multitude of other uses; e.g., in the preparation of mortar, cement, and concrete.

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Universalium. 2010.

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  • Sand — Sand, n. [AS. sand; akin to D. zand, G. sand, OHG. sant, Icel. sandr, Dan. & Sw. sand, Gr. ?.] 1. Fine particles of stone, esp. of siliceous stone, but not reduced to dust; comminuted stone in the form of loose grains, which are not coherent when …   The Collaborative International Dictionary of English

  • Sand — mit Rippelmarken Sand ist ein natürlich vorkommendes, unverfestigtes Sedimentgestein, das sich aus einzelnen Sandkörnern mit einer Korngröße von 0,063 bis 2 mm zusammensetzt. Damit ordnet sich der Sand zwischen dem Feinkies (Korngröße 2 bis… …   Deutsch Wikipedia

  • Sand — [zant], der; [e]s, e: Substanz, die durch Verwitterung von Gestein entstanden ist und aus feinen Körnern besteht: gelber, weißer, feiner, grober Sand; die Kinder spielen im Sand; aus verschiedenen Sanden (Sorten von Sand) bestehender Boden. Zus …   Universal-Lexikon

  • Sand — Pour les articles homonymes, voir Sand (homonymie). Sand …   Wikipédia en Français

  • Sand — Sand: Das altgerm. Wort mhd., ahd. sant, niederl. zand, engl. sand, schwed. sand ist verwandt mit griech. ámathos »Sand«. Die weiteren Beziehungen sind unklar. – Abl.: sandig (mhd. sandic). Zus.: Sandbank (17. Jh.). • Sand wie Sand am Meer… …   Das Herkunftswörterbuch

  • Sand (DC) — Sand (comics) Pour les articles homonymes, voir sand (homonymie). Sand Personnage de Sandman …   Wikipédia en Français

  • SAND (G.) — Renan écrivait au lendemain des obsèques de George Sand, morte à Nohant: «Une corde est brisée dans la lyre du siècle [...]. Mme Sand traversa tous les rêves; elle sourit à tous, crut un moment à tous; son jugement pratique put parfois s’égarer,… …   Encyclopédie Universelle

  • sand — [sand] n. [ME < OE, akin to Ger sand, ON sandr < IE base * bhes , to rub off, pulverize > Gr psammos, L sabulum] 1. loose, gritty particles of eroded or weathered rock, varying in size from about 1/ 16 mm to 2 mm in diameter, usually… …   English World dictionary

  • Sand — Saltar a navegación, búsqueda Para otros usos de este término, véase SAND. Sand País …   Wikipedia Español

  • Sand — Sand, v. t. [imp. & p. p. {Sanded}; p. pr. & vb. n. {Sanding}.] 1. To sprinkle or cover with sand. [1913 Webster] 2. To drive upon the sand. [Obs.] Burton. [1913 Webster] 3. To bury (oysters) beneath drifting sand or mud. [1913 Webster] 4. To mix …   The Collaborative International Dictionary of English

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