[kal-sed-n-ee, kal-suh-doh-nee] 
| a microcrystalline, translucent variety of quartz, often milky or grayish. |
n chalcedony, identified by Saint Jerome with Chalcedon, the city) + -ius -ious 
[kal-si-don-ik] , chal⋅ced⋅o⋅nous, adjective | chal·ced·o·ny also cal·ced·o·ny (kāl-sěd'n-ē) n. pl. chal·ced·o·nies also cal·ced·o·nies A translucent to transparent milky or grayish quartz with distinctive microscopic crystals arranged in slender fibers in parallel bands. [Late Latin chalcēdonius, from Greek khalkēdōn, a mystical stone (Revelation 21:19), perhaps from Khalkēdōn, Chalcedon.] chal'ce·don'ic (kāl'sĭ-dŏn'ĭk) adj. |
| chalcedony (kāl-sěd'n-ē) Pronunciation Key
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: SiO2. |