chalcedony

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

noun

, plural chal·ced·o·nies.

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

/ 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 .

Derived Forms

• chalcedonic, adjective

Other Words From

• chal·ce·don·ic [kal-si-, don, -ik], chal·cedo·nous 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.

From New York Times

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

“Red agate and White Opal with Botryodial Chalcedony,” to be exact, according to tweet.

From Fox News

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 Literature

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.”

From The New Yorker