• Webster's Revised Unabridged Dictionary
    • n Labradorite (Min) A kind of feldspar commonly showing a beautiful play of colors, and hence much used for ornamental purposes. The finest specimens come from Labrador. See Feldspar.
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Century Dictionary and Cyclopedia
    • n labradorite A lime-soda feldspar (see feldspar), one of the species intermediate between the lime feldspar, anorthite, and the soda feldspar, albite, but more closely allied to the former. It is a common constituent of igneous rocks, especially of these of the basaltic type. It is rarely found crystallized, but usually in masses, and these often show a brilliant change of colors; on this account it. is sometimes used as an ornamental stone. The finest specimens come from the coast of Labrador, whence the name.
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Chambers's Twentieth Century Dictionary
    • n Labradorite lab′ra-dōr-īt one of the group of the Feldspars, and a very important rock-forming mineral.
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Chambers's Twentieth Century Dictionary


In literature:

The waters were deep and black, the shores were steep and rocky, and some labradorite was seen.
"The Long Labrador Trail" by Dillon Wallace
At Napatuliarasok Island are some lovely specimens of blue and green and golden Labradorite, a striated feldspar with a glorious sheen.
"A Labrador Doctor" by Wilfred Thomason Grenfell
Labradorite, the reader may know, is a crystallized feldspar, with traces of other minerals.
"The Atlantic Monthly, Volume 15, No. 87, January, 1865" by Various
Labradorite, 214; potash in, 220.
"Manures and the principles of manuring" by Charles Morton Aikman
The feldspar gems, such as moonstone, amazonite, and labradorite, also cleave very smoothly in certain directions.
"A Text-Book of Precious Stones for Jewelers and the Gem-Loving Public" by Frank Bertram Wade
Essentially it is a crystalline-granular compound of plagioclase, generally Labradorite and diallage.
"Volcanoes: Past and Present" by Edward Hull
It is composed of a prehistoric grey labradorite, and of doleritic lava.
"Etna" by G. F. Rodwell
It would be just as sensible to say that labradorite, which is rare, should be as costly as diamonds.
"The Story of the Trapper" by A. C. Laut
These intermediate members are the lime-soda felspars known as oligoclase, andesine, labradorite and bytownite.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 2" by Various