[floo r-ahyt, flawr-, flohr-]


a common mineral, calcium fluoride, CaF2, occurring in green, blue, purple, yellow, or colorless crystals, usually in cubes: the principal source of fluorine, used also as a flux in metallurgy and for ornament.

Origin of fluorite

From Italian, dating back to 1865–70; see origin at fluor-, -ite1
Also called fluor, fluorspar, fluor spar.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for fluorite

Historical Examples of fluorite

  • Only certain varieties of fluorite show the phenomenon well.

  • Some specimens of fluorite (CaF2) show the phenomenon especially well, whence the name fluorescence.

  • Agricola derived the name fluores from fluo "to flow," and we in turn obtain "fluorite," or "fluorspar," from Agricola.

    De Re Metallica

    Georgius Agricola

  • Rays passing through the fluorite window strike the blackened side of the mica, which is parallel and opposite to it.

  • In England, fluorite is obtained in this manner as a by-product from lead and zinc mines.

British Dictionary definitions for fluorite



US and Canadian a white or colourless mineral sometimes fluorescent and often tinted by impurities, found in veins and as deposits from hot gases. It is used in the manufacture of glass, enamel, and jewellery, and is the chief ore of fluorine. Composition: calcium fluoride. Formula: CaF 2 . Crystal structure: cubicAlso called (in Britain and certain other countries): fluorspar, fluor
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

fluorite in Science



A transparent to translucent mineral occurring in many colors, especially yellow and purple, and usually in cube-shaped crystals with octahedral cleavage. It is found in sedimentary rocks and in ore deposits within igneous rocks. It is often fluorescent in ultraviolet light. Chemical formula: CaF2.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.