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[too r-muh-lin, -leen] /ˈtʊər mə lɪn, -ˌlin/
any of a group of silicate minerals of complex composition, containing boron, aluminum, etc., usually black but having various colored, transparent varieties used as gems.
Also, tourmalin
[too r-muh-lin] /ˈtʊər mə lɪn/ (Show IPA),
Origin of tourmaline
1750-60; earlier tourmalin < German Turmalin, ultimately < Sinhalese tōramalliya carnelian; see -in2
Related forms
[too r-muh-lin-ik] /ˌtʊər məˈlɪn ɪk/ (Show IPA),
adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for tourmaline
  • Unique coastal gifts include handmade scrimshaws and jewelry featuring tourmaline, the state gemstone.
  • tourmaline seems to have a special place in the hearts of mineral collectors as well as in that of gem and gemstone enthusiasts.
  • tourmaline is used as a semiprecious gemstone when found in transparent crystals of red, pink, green or blue color.
  • Often the composition consists of garnet, tourmaline, and mica.
  • tourmaline is a common accessory mineral at several copper mineralized breccia deposits.
  • Look up the formula for the mineral tourmaline, record it below.
  • tourmaline is optically anisotropic, and dark examples do completely absorb the o-ray.
  • Red mudstone is typically altered to indurated, bluish-gray hornfels with clots or crystals of tourmaline or cordierite.
  • The highest values are found in tourmaline-bearing veins.
  • Minerals hidden within the schist may include pyrite, antimony, tourmaline and actinolite.
British Dictionary definitions for tourmaline


any of a group of hard glassy minerals of variable colour consisting of complex borosilicates of aluminium with quantities of lithium, sodium, calcium, potassium, iron, and magnesium in hexagonal crystalline form: used in optical and electrical equipment and in jewellery
Derived Forms
tourmalinic (ˌtʊəməˈlɪnɪk) adjective
Word Origin
C18: from German Turmalin, from Sinhalese toramalli carnelian
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
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Word Origin and History for tourmaline

complete silicate of aluminum and boron, 1759, ultimately from Sinhalese toramalli, a general name for cornelian.

Online Etymology Dictionary, © 2010 Douglas Harper
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tourmaline in Science
  (tr'mə-lĭn, -lēn')   
Any of several minerals having the general chemical formula (Na,Ca)(Mg,Fe,Al,Li)3Al6(BO3)3Si6O18(OH)4. Tourmaline occurs in many different translucent colors, usually in crystals shaped like 3-, 6-, or 9-sided prisms. It occurs in igneous and metamorphic rocks, especially in pegmatites.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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