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Epsom salts

(Encyclopedia)Epsom salts, common name for magnesium sulfate heptahydrate, MgSO4·7H2O, a water-soluble bitter-tasting compound that occurs as white or colorless needle-shaped crystals. It was first prepared from t...

die-casting

(Encyclopedia)die-casting, process by which molten metal is forced by a plunger or compressed air into a metallic die and the pressure maintained until the metal has solidified. Die castings are accurate, are sharp...

spinel

(Encyclopedia)spinel, magnesium aluminum oxide, MgAl2O4, a mineral crystallizing in the isometric system, usually as octahedrons. It occurs as an accessory mineral in basic igneous rocks, in aluminum-rich metamorph...

corrosion

(Encyclopedia)corrosion, atmospheric oxidation of metals (see oxidation and reduction). By far the most important form of corrosion is the rusting of iron. Rusting is essentially a process of oxidation in which iro...

deliquescence

(Encyclopedia)deliquescence dĕlˌəkwĕsˈəns [key], conversion of a solid substance into a liquid as a result of absorption of water vapor from the air. Since impurities in a solid lower its melting point, the a...

Béchar

(Encyclopedia)Béchar kôlôNˈ– [key], town, capital of Béchar prov., W Algeria. It is an important adm...

Öskemen

(Encyclopedia)Öskemen o͝ostˌ-kəmyĭnəgôrskˈ [key], city (1989 pop. 324,478), NE Kazakhstan, on the Irtysh River and in the foothills of the W Altai Mts. It is a river port and an industrial center with zinc,...

mica

(Encyclopedia)mica mīˈkə [key], general term for a large group of minerals, hydrous silicates of aluminum and potassium, often containing magnesium, ferrous iron, ferric iron, sodium, and lithium and more rarely...

serpentine

(Encyclopedia)serpentine sûrˈpəntēn, –tīn [key], hydrous silicate of magnesium. It occurs in crystalline form only as a pseudomorph having the form of some other mineral and is generally found in the form of...

pyroxene

(Encyclopedia)pyroxene pīˈrŏksēn [key], name given to members of a group of widely distributed rock minerals called metasilicates in which magnesium, iron, and calcium, often with aluminum, sodium, lithium, man...