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.

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chalcedony British  

/ kælˈsɛdənɪ /

noun

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

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chalcedony Scientific  

/ kăl-sĕd′n-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 .

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Other Word Forms

Derived Forms

• chalcedonic
  adjective
• chalcedonous
  adjective

Inflected Forms

Nouns

• chalcedonies
  plural

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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

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Example Sentences

See Examples For:

chalcedony chalcedonies

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

One supposed mammal tooth was actually a bit of the mineral chalcedony.

From New York Times ● Feb. 21, 2023

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

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

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

Ceraunia, engendered by the thunder, sparkled by the side of chalcedonies, which are a cure for poison.

From Salammbo by Gustave Flaubert

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

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

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

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