chalcedony

[kal-sed-n-ee, kal-suh-doh-nee]

noun

plural

chalcedonies 

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

chalcedony

/ kælˈsɛdənɪ, ˌkælsɪˈdɒnɪk /

noun

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

chalcedony

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

• chalcedonic adjective
• chalcedonous adjective

Word History and Origins

Origin of chalcedony¹

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; -ious

Word History and Origins

Origin of chalcedony¹

C15: from Late Latin chalcēdōnius, from Greek khalkēdōn a precious stone (Revelation 21:19), perhaps named after Khalkēdōn Chalcedon, town in Asia Minor

Example Sentences

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

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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.

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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.

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Speakers of English sometimes have trouble knowing how to pronounce Greek-derived words with “ch” in them—“chalcedony,” “chiropodist,” “chimera”—because “ch” also represents the sound in such English words as “church” and “cheese.”

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With any luck, the territory would contain flint, jasper, or chalcedony, the raw material for spear points, meat scrapers, and other hunting tools.

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