“jadeite”的意思、由来-百科全书

jadeite

mineral

gem-quality silicate mineral in the pyroxene family that is one of the two forms of jade (q.v.). The more prized of the two types of jade, jadeite (imperial jade) is usually found as transparent-to-opaque, compact, cryptocrystalline lenses, veins, or nodules. It may be distinguished from nephrite (mutton-fat jade), jade's other form, by its granular fracture and glassy lustre; in addition, polished surfaces often show pitting caused by varying hardness. Jadeite, sodium aluminum silicate (NaAlSi₂O₆), may contain a number of impurities (often calcium) that give it a variety of colours: white, emerald green, apple green, red, brown, and blue. Deep green to greenish black varieties are called chloromelanite and are coloured by iron.

Jadeite occurs only in metamorphic rocks, most often in those that have been subjected to the high pressures deep below the Earth's surface. Jadeite is rare; its presence at the surface indicates great uplift of earlier buried regions and great amounts of erosion. The most important source is the large deposit near Tawmaw, Myanmar (Burma). Jadeite has also been found near Omi and Kotaki, Japan; in the Motagua River valley of Guatemala; in San Benito county, Calif.; Kazakhstan; and the Ural Mountains, Russia.

For detailed physical properties of jadeite, see gemstone (table); pyroxene (table).

词条	jadeite
释义	jadeite mineral gem-quality silicate mineral in the pyroxene family that is one of the two forms of jade (q.v.). The more prized of the two types of jade, jadeite (imperial jade) is usually found as transparent-to-opaque, compact, cryptocrystalline lenses, veins, or nodules. It may be distinguished from nephrite (mutton-fat jade), jade's other form, by its granular fracture and glassy lustre; in addition, polished surfaces often show pitting caused by varying hardness. Jadeite, sodium aluminum silicate (NaAlSi₂O₆), may contain a number of impurities (often calcium) that give it a variety of colours: white, emerald green, apple green, red, brown, and blue. Deep green to greenish black varieties are called chloromelanite and are coloured by iron. Jadeite occurs only in metamorphic rocks, most often in those that have been subjected to the high pressures deep below the Earth's surface. Jadeite is rare; its presence at the surface indicates great uplift of earlier buried regions and great amounts of erosion. The most important source is the large deposit near Tawmaw, Myanmar (Burma). Jadeite has also been found near Omi and Kotaki, Japan; in the Motagua River valley of Guatemala; in San Benito county, Calif.; Kazakhstan; and the Ural Mountains, Russia. For detailed physical properties of jadeite, see gemstone (table); pyroxene (table).
随便看	Fernando del Paso Fernando de, Marqués De Villa Sierra Valenzuela Fernando de Noronha Island Fernando de Rojas Fernando de Valenzuela, Marqués De Villa Sierra Fernando Francesco de Avalos, marchese di Pescara Fernando Francesco de Avalos Pescara, marchese di Fernando Goncalves Namora Fernando Henrique Cardoso Fernando Lugo Fernando Monteiro de Castro Soromenho Fernando Ortiz Fernando Pessoa Fernando Romeo Lucas García Fernando Valenzuela Fernando Wood Fernando Álvarez de Toledo y Pimentel, 3er duque de (3rd duke of) Alba Fernando Álvarez de Toledo y Pimentel Alba, 3er duque de (3rd duke of) Fernand Pelloutier fern moss Fernán Caballero Fernández de Avellaneda, Alonso Fernández de Córdoba, Gonzalo Fernández de Kirchner, Cristina Fernández de Lizardi, José Joaquín