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

The pleochroism is strong, the pleochroic colours being usually green, yellow and brown.

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

Such an effect is called pleochroism, and crystals which show variations in their colour when viewed from different angles, or by transmitted light, are called pleochroic, or pleochromatic—from two Greek words signifying "to colour more."

From The Chemistry, Properties and Tests of Precious Stones by John Mastin

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

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