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chalcedony

American  
[kal-sed-uhn-ee, kal-suh-doh-nee] / kælˈsɛd ən i, ˈkæl səˌdoʊ ni /

noun

  • chalcedonies
    plural
  1. a microcrystalline, translucent variety of quartz, often milky or grayish.


chalcedony British  
/ kælˈsɛdənɪ, ˌkælsɪˈdɒnɪk /

noun

  1. a microcrystalline often greyish form of quartz with crystals arranged in parallel fibres: a gemstone. Formula: SiO 2

"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

chalcedony Scientific  
/ kăl-sĕdn-ē /
  1. A type of quartz that has a waxy luster and varies from transparent to translucent. It is usually white, pale-blue, gray, brown, or black and is often found as a lining in cavities. Agate, flint, and onyx are forms of chalcedony. Chemical formula: SiO 2 .


Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of chalcedony

First recorded in 1275–1325; Middle English calcedonie, from Late Latin chalcēdōnius (Vulgate, Revelation 21:19), equivalent to chalcēdōn- (from Greek chalkēdṓn “chalcedony,” identified by Saint Jerome with Chalcedon, the city) + -ius adjective suffix; see -ious

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Encased in blue chalcedony, set with diamonds and hung from a black silk ribbon, the piece is a contemporary interpretation of Baillères’ Mexican heritage.

From Los Angeles Times Apr. 9, 2026

The outfit was by 4SDesigns, but that the accompanying chain around his neck was an 18-karat white gold, platinum, chalcedony, turquoise and diamond necklace by Cartier somewhat complicated the point.

From New York Times May 3, 2022

Watts gleamed in jewels, pairing her pavé diamond rings with a dazzler of a sapphire, diamond and chalcedony necklace.

From Los Angeles Times Feb. 19, 2015

The subtle color mixes included lilac diamonds with lavender chalcedony, purple sapphires and pink spinels.

From New York Times Jul. 4, 2011

The box was carved wood, its mother-of-pearl lid inlaid with jasper and chalcedony.

From "A Clash of Kings" by George R.R. Martin

But flint is the staple of the broad Culm Valley, under good, well-pastured loam; and here are chalcedonies and agate stones.

From Crocker's Hole From "Slain By The Doones" By R. D. Blackmore by R. D. (Richard Doddridge) Blackmore

Emeralds abound in the region about Mount Zabara, and the eastern desert further yields jaspers, carnelians, breccia verde, agates, chalcedonies, and rock-crystal.

From Ancient Egypt by George Rawlinson

Even precious stones are not wanting; garnets, topazes, tourmalines, amethysts, beryls, jaspers, and chalcedonies having been found.

From A Tramp's Wallet stored by an English goldsmith during his wanderings in Germany and France by William Duthie

The diamonds of this district are noted for their purity and lustre, and are generally associated with other crystals—garnets, agates, quartz and chalcedonies.

From Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 3 "Banks" to "Bassoon" by Various

There were rich red garnets, variegated jaspers, chalcedonies and agates of many hues mingled with rock-crystals.

From Wealth of the World's Waste Places and Oceania by Jewett Castello Gilson

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