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[soo-duh-mawrf] /ˈsu dəˌmɔrf/
an irregular or unclassifiable form.
a mineral having the outward appearance of another mineral that it has replaced by chemical action.
1840-50; pseudo- + -morph
Related forms
pseudomorphic, pseudomorphous, adjective
pseudomorphism, noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for pseudomorph
  • The serpentine occurs typically in the form of a pseudomorph after diallage.
British Dictionary definitions for pseudomorph


a mineral that has an uncharacteristic crystalline form as a result of assuming the shape of another mineral that it has replaced
Derived Forms
pseudomorphic, pseudomorphous, adjective
pseudomorphism, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Word Origin and History for pseudomorph

"irregular form," 1838, earlier in German and French, from pseudo- + Greek morphe "form" (see Morpheus). Related: Pseudomorphic.

Online Etymology Dictionary, © 2010 Douglas Harper
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Encyclopedia Article for pseudomorph

mineral formed by chemical or structural change of another substance, though retaining its original external shape. Although pseudomorphs give the appearance of being crystalline, they are commonly granular and waxy internally and have no regular cleavage; those that are crystalline have optical properties different from those required by their outward form

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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