anorthite

American  

[an-awr-thahyt] / ænˈɔr θaɪt /

noun

Mineralogy.

1. a white or gray feldspar mineral, CaAl 2 Si 2 O 8 , calcic plagioclase.

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anorthite British  

/ ænˈɔːθaɪt, ˌænɔːˈθɪtɪk /

noun

1. a white to greyish-white or reddish-white mineral of the feldspar group and plagioclase series, found chiefly in igneous rocks and more rarely in metamorphic rocks. It is used in the manufacture of glass and ceramics. Composition: calcium aluminium silicate. Formula: CaAl 2 Si 2 O 8 . Crystal structure: triclinic

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anorthite Scientific  

/ ăn-ôr′thīt /

1. A white to gray triclinic mineral of the plagioclase feldspar group. Anorthite is the plagioclase mineral that is richest in calcium and occurs in alkaline igneous rocks such as gabbro. Chemical formula: CaAl ₂ Si ₂ O ₈ .

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Other Word Forms

• anorthitic
  adjective

Etymology

Origin of anorthite

First recorded in 1825–35; an- ¹ + orth- + -ite ¹

Example Sentences

See Examples For:

anorthite

Practically all varieties of this mineral from anorthite to albite are known to occur in basalt, but by far the commonest species are bytownite and labradorite.

From Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 3 "Banks" to "Bassoon" by Various

The name anorthite was given to the Vesuvian mineral by G. Rose in 1823, on account of its anorthic crystallization.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 2 "Anjar" to "Apollo" by Various

Their commonest minerals are olivine, anorthite, hornblende, augite, biotite and leucite.

From The Project Gutenberg Encyclopedia Volume 1 of 28 by Project Gutenberg

Like labradorite and anorthite, it is a common constituent of basic igneous rocks, such as gabbro and basalt.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" by Various

The name was afterwards applied by G. Tschermak to those plagioclase felspars which lie between labradorite and anorthite; and this has been generally adopted by petrologists.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4 "Bulgaria" to "Calgary" by Various