• synonyms


[uh-pof-uh-lahyt, ap-uh-fil-ahyt]
  1. a hydrous potassium and calcium silicate mineral occurring in white crystals.
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Origin of apophyllite

First recorded in 1800–10; apo- + -phyll + -ite1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for apophyllite

Historical Examples

  • Apophyllite, a species of mineral of a foliated structure and pearly lustre, called also fish-eye stone.

    The New Gresham Encyclopedia. Vol. 1 Part 2


  • Apophyllite always occurs as distinct crystals, which belong to the tetragonal system.

British Dictionary definitions for apophyllite


  1. a white, colourless, pink, or green mineral consisting of a hydrated silicate of calcium, potassium, and fluorine in tetragonal crystalline form. It occurs in cracks in volcanic rocks. Formula: KCa 4 (Si 4 O 10) 2 (OH 1 F).8H 2 O
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Word Origin

C19: from French, from apo- + Greek phullon leaf + -ite 1; referring to its tendency to exfoliate
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012