amethyst
1. a purple or violet transparent variety of quartz used as a gemstone. Formula: SiO2
2. a purple variety of sapphire; oriental amethyst
3. the purple colour of amethyst
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
amethyst
[′am·ə‚thist] (mineralogy)
The transparent purple to violet variety of the mineral quartz; used as a jeweler's stone.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
amethyst
February. [Am. Gem Symbolism: Kunz, 319–320]
amethyst
preserved soldiers from harm; gave them victory. [Gem Symbolism: Kunz, 58]
amethyst
provides protection against drunkenness; February birthstone. [Gem Symbolism: Kunz, 58–59]
Allusions—Cultural, Literary, Biblical, and Historical: A Thematic Dictionary. Copyright 2008 The Gale Group, Inc. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.
Amethyst
a mineral, a violet or sky blue-violet variety of quartz (SiO2). On heating to 300–350°C, amethyst becomes yellow or is discharged. Decolorized amethyst reacquires its color after exposure to X rays. The mineral occurs in quartz veins, granitic rocks, amygdules of volcanic rocks, and sometimes in sedimentary rocks, such as silicon salts. The best specimens are used for jewelry and as ornamental stones. Especially fine are amethysts from the Urals and Brazil. A blue-violet variety of corundum is known in the jeweler’s craft as eastern amethyst.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.