pleochroism

American  

[plee-ok-roh-iz-uhm] / pliˈɒk roʊˌɪz əm /

noun

1. the property of certain crystals of exhibiting different colors when viewed from different directions under transmitted light.

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pleochroism British  

/ ˌpliːəˈkrəʊɪk, plɪˈɒkrəʊˌɪzəm /

noun

1. a property of certain crystals of absorbing light to an extent that depends on the orientation of the electric vector of the light with respect to the optic axes of the crystal. The effect occurs in uniaxial crystals ( dichroism ) and esp in biaxial crystals ( trichroism )

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Other Word Forms

• pleochroic adjective

Etymology

Origin of pleochroism

First recorded in 1855–60; pleochro(ic) + -ism

Example Sentences

Biotite, containing haloes, 223; pleochroism of, 235; intensified pleochroism in halo, 235.

From The Birth-Time of the World and Other Scientific Essays by Joly, John

Biotite is, however, readily distinguished by its darker colour, strong pleochroism, and small optic axial angle.

From Encyclopaedia Britannica, 11th Edition, Volume 3, Slice 7 "Bible" to "Bisectrix" by Various

The crystallographic and optical characters are similar to those of epidote; the pleochroism is strong with reddish-, yellowish-, and greenish-brown colours.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 6 "English Language" to "Epsom Salts" by Various

Iceland-spar is extensively used in the construction of Nicol's prisms for polariscopes, polarizing microscopes and saccharimeters, and of dichroscopes for testing the pleochroism of gem-stones.

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

A very useful means of discriminating between certain stones is found in their dichroism, or, to use a more general term, pleochroism.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 5 "Gassendi, Pierre" to "Geocentric" by Various