Chalcedon. City in Asia Minor near Constantinople and venue of the fourth ecumenical council in 451. By drawing up a statement of faith, the so-called Chalcedonian definition, it attempted to end the controversy between Alexandrian and Antiochene christologies. The strong Monophysite party in the E. never accepted the definition, and until Islamic times repeated attempts were made by ‘neo-Chalcedonians’ to remove its offence without actually rescinding it. The Oriental Orthodox churches still remain ‘non-Chalcedonian’.

Chalcedony

A silica mineral related to quartz. Superstition credits chalcedony with magical and medicinal properties. It is a good specific against fantasy and illusions of evil spirits. It supposedly quickens the power of the body and renders its possessor fortunate in law. To achieve the latter effect, it is to be perforated and suspended by hairs from a donkey. The black variety is believed to prevent hoarseness and clear the voice.

chalcedony a microcrystalline type of quartz occurring in several different forms including onyx and agate. The word comes (in late Middle English) from Latin chalcedonius (often believed to mean ‘stone of Chalcedon’, but this is doubtful), which in the Vulgate represents Greek khalkēdōn, the name (in Revelation 21:19) of the precious stone forming the third foundation of the New Jerusalem.

chalcedony The group name for cryptocrystalline varieties of silica composed of minute crystals of quartz with submicroscopic pores and with composition ranging from SiO₂ to SiO₂.nH₂O and including the minerals agate, chert, opal, onyx, jasper, and flint; sp. gr. 2.50–2.67; habits variable from stalactitic to massive; commonly white, greyish-white, or grey, and occasionally yellow.

chal·ced·o·ny / kalˈsednˌē; chal-; ˈkalsəˌdōnē; ˈchalsə-/ • n. (pl. -nies) a microcrystalline type of quartz occurring in several different forms, including onyx, agate, and jasper. DERIVATIVES: chal·ce·don·ic / ˌkalsəˈdänik/ adj.

chalcedony Microcrystalline form of quartz. When cut and polished, it is used by gem engravers. It is waxy, lustrous and there are white, grey, blue and brown varieties. Often coloured by artificial methods, some varieties contain impurities giving a distinctive appearance, such as agate (coloured bands), onyx (striped) and bloodstone (dark green with red flecks).

Chalcedon (kăl´sĬdŏn, –dən, kălsē´dən), ancient Greek city of Asia Minor, on the Bosporus. It was founded by Megara on the shore opposite Byzantium in 685 BC Taken by the Persians and recovered by the Greeks, it was later a possession of the kings of Bithynia, from whom it passed (AD 74) to Rome. The Council of Chalcedon was held there in AD 451. The site is in the suburbs of İstanbul.

chalcedony (kălsĕd´ənē) [from Chalcedon], form of quartz the crystals of which are so minute that its crystalline structure cannot be seen except with the aid of a microscope. Chalcedony has a waxy luster and is translucent to transparent. The name chalcedony is applied more specifically to white, gray, blue, and brown varieties. Some varieties, differing in color because of the presence of impurities, are agate, bloodstone, carnelian, chrysoprase, jasper, onyx, sard, and sardonyx.

Chalcedon •radon • Chalcedon • Proudhon •Mogadon • pteranodon • iguanodon •mastodon • chiffon • Ctesiphon •bouffant • balafon • Xenophon •Bellerophon •argon, Sargon •Dagon • woebegone • bygone •doggone, logon •dodecagon • Dijon • demijohn • ancon •archon • racon • Comecon • emoticon •stereopticon • icon • walk-on • neocon •Yukon • zircon • salon • Fablon •decathlon • Teflon • Dralon • Simplon •Babylon • papillon • propylon •epsilon • nylon • Orlon •eidolon, roll-on, Solon •mouflon • Ascalon • Ashqelon •echelon • Avalon •gnomon, Jomon

chalcedony •Léonie, peony •Tierney •Briony, bryony, Hermione •tourney • ebony • Albany •chalcedony • Alderney •Persephone, Stephanie, telephony •antiphony, epiphany, polyphony, tiffany •symphony •cacophony, homophony, theophany, Zoffany •euphony • agony • garganey •Antigone •cosmogony, mahogany, theogony •balcony • Gascony • Tuscany •calumny •felony, Melanie, miscellany •villainy • colony •Chamonix, salmony, scammony, Tammany •harmony •anemone, Emeny, hegemony, lemony, Yemeni •alimony, palimony •agrimony • acrimony •matrimony, patrimony •ceremony • parsimony • antimony •sanctimony • testimony • simony •Romany • Germany • threepenny •timpani • sixpenny • tuppenny •accompany, company •barony • saffrony • tyranny •synchrony • irony • saxony • cushiony •Anthony • betony •Brittany, dittany, litany •botany, cottony, monotony •gluttony, muttony •Bethany • oniony • raisiny •attorney, Burney, Czerny, Ernie, ferny, gurney, journey, Verny