Definitions

from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun The property possessed by some crystals of exhibiting different colors, especially three different colors, when viewed along different axes.

from The Century Dictionary.

  • noun In crystallography, the variation in color observed in some crystals when viewed in different directions, due to the fact that the rays having vibrations in different planes suffer absorption in different degrees.

from the GNU version of the Collaborative International Dictionary of English.

  • noun (Crystallog.) The property possessed by some crystals, of showing different colors when viewed in the direction of different axes.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun physics The optical phenomenon in some colored, transparent crystals (such as tourmaline) in which the color is different in different directions.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun the phenomenon of different colors appearing when certain crystals are viewed from different directions

Etymologies

from The American Heritage® Dictionary of the English Language, 4th Edition

[pleo– + Greek khrōs, color + –ism.]

Examples

  • 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."

    The Chemistry, Properties and Tests of Precious Stones

  • 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.

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

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

    The Birth-Time of the World and Other Scientific Essays

  • Because of Iolite's pleochroism (it appears a different color depending on the angle of the light), they could look through the mineral to determine the sun's exact position and navigate accurately.

    de.lirio.us

  • Because of Iolite's pleochroism (it appears a different color depending on the angle of the light), they could look through the mineral to determine the sun's exact position and navigate accurately.

    de.lirio.us

  • Because of Iolite's pleochroism (it appears a different color depending on the angle of the light), they could look through the mineral to determine the sun's exact position and navigate accurately.

    de.lirio.us

Comments

New comments are temporarily disabled while we update our database.

  • Purty purty.

    September 30, 2008

  • A rock hound when he is wistful

    dreams gemstones garnered by fistful,

    And rock turned to prism

    By pleochroism -

    The trick of a magical crystal.

    August 20, 2016