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

---

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 .

---

Other Word Forms

Derived Forms

• chalcedonic
  adjective
• chalcedonous
  adjective

Inflected Forms

Nouns

• chalcedonies
  plural

---

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

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

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

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

From Salammbo by Gustave Flaubert

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

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

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

Random Word

Spin the wheel and learn a new word!

---