Chalcedon
Chalcedon ( or ;
, sometimes transliterated as "Chalkedon") was an ancient maritime town of Bithynia, in Asia Minor. It was located almost directly opposite Byzantium, south of Scutari (modern Üsküdar) and it is now a district of the city of Istanbul named Kadıköy. The name "Chalcedon" is a variant of Calchedon, found on all the coins of the town as well as in manuscripts of Herodotus's "Histories", Xenophon's "Hellenica", Arrian's "Anabasis", and other works. Except for a tower, almost no above-ground vestiges of the ancient city survive in Kadıköy today; artifacts uncovered at Altıyol and other excavation sites are on display at the Istanbul Archaeological Museum.
Chalcedony
The name "chalcedony" comes from the Latin "chalcedonius" (alternatively spelled "calchedonius"). The name appears in Pliny the Elder's "Naturalis Historia" as a term for a translucid kind of Jaspis. The name is probably derived from the town Chalcedon in Asia Minor. The Greek word "khalkedon" (χαλκηδών) also appears in the Book of Revelation (Apc 21,19). It is a hapax legomenon found nowhere else, so it is hard to tell whether the precious gem mentioned in the Bible is the same mineral known by this name today.