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

See Examples For:

pleochroism

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

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

The colour is dark grey or green; a characteristic feature is the pleochroism, the pleochroic colours varying from yellowish-green to indigo-blue.

From Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 5 "Clervaux" to "Cockade" by Various

The last mentioned is a bright blue variety of hornblende with striking pleochroism.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 10 "Echinoderma" to "Edward" by Various

The pleochroism of some crystals is so strong that when they are viewed through in different directions they exhibit marked differences in colour.

From Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 7 "Crocoite" to "Cuba" by Various