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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 /

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 National Museum of the American Indian displays about 100 Pepper artifacts near the fourth-floor elevator entrance, mostly jasper and chalcedony blades that date back as far as 10,000 B.C.

From New York Times Jul. 22, 2010

He’s also brought down a few pieces of furniture I recognize from the palace—a silk-embroidered divan, satin cushions, a shimmering spider-silk throw, and a chalcedony set of tea things.

From "The Cruel Prince" by Holly Black

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

It is overrun with vines and 159 flowers, cut in stone, and set with onyx and jasper and lapis lazuli, carnelians and turquoises, and chalcedonies and sapphires.

From From Egypt to Japan by Henry M. (Henry Martyn) Field

She had filled her pockets with specimens of obsidian, jaspers, and chalcedonies, of colors most beautiful, with a deep-dyed opaqueness, a shell-fracture, and a satiny polish like jade.

From A Touch of Sun and Other Stories by Mary Hallock Foote

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

The flints in Sandown Bay have in the main travelled round from here; and towards the Culvers small handy specimens of agates and chalcedonies rounded by the waves may be collected.

From The Geological Story of the Isle of Wight by J. Cecil Hughes

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