andradite


andradite
/an"dreuh duyt'/, n.
a mineral, calcium-iron garnet, Ca3Fe2Si3O2, occurring in brown, green, or black crystals.
[1830-40; named after J. B. de ANDRADA E SILVA; see -ITE1]

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 calcium-iron garnet, perhaps the most spectacular garnet because of its high dispersion (separation of light into colours), even greater than that of diamond, and refractive index. It is found in various colours, some of the most beautiful being yellowish (termed topazolite, because of its resemblance to topaz) and yellowish green or emerald-green (Uralian emeralds, or demantoid). Titanium may extensively replace both the iron and the silicon, as in schorlomite, or may simply produce a black colour, as in melanite. Andradite is typically found with grossular in contact-metamorphosed limestone. For details of chemistry and occurrence, see garnet.

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Universalium. 2010.

Look at other dictionaries:

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  • andradite — [an′drə dīt΄] n. [after J. B. de Andrada ( c. 1763 1838), Brazilian geologist] a variety of garnet, Ca3Fe2 (SiO4) 3, sometimes used as a gem …   English World dictionary

  • andradite — andraditas statusas T sritis chemija apibrėžtis Granatų grupės mineralas. formulė Ca₃Fe₂[SiO₄]₃ atitikmenys: angl. andradite rus. андрадит …   Chemijos terminų aiškinamasis žodynas

  • andradite — noun Etymology: José B. de Andrada e Silva died 1838 Brazilian geologist Date: 1868 a calcium iron garnet occurring in various colors ranging from yellow and green to brown and black …   New Collegiate Dictionary

  • andradite — noun A nesosilicate mineral of the garnet group with chemical formula CaFeSiO …   Wiktionary

  • andradite — an·dra·dite …   English syllables

  • andradite — an•dra•dite [[t]ˈæn drəˌdaɪt[/t]] n. mir a garnet occurring in brown, green, or black crystals • Etymology: 1830–40; after J. B. de Andrada e Silva; see ite I …   From formal English to slang

  • andradite — /ˈændrədaɪt/ (say andruhduyt) noun a mineral, calcium iron garnet, Ca3Fe2Si3O12, occurring in brown, green, or black crystals. {named after José Bonifacio d Andrada e Silva, 1763–1838, Brazilian mineralogist. See ite1} …   Australian English dictionary