Chalcedony (χαλκηδών)
Chalcedony is the precious stone with which the third foundation of the wall of the New Jerusalem is garnished (Revelation 21:19). The ancient meaning of the word is uncertain. In modern mineralogy the chalcedony is ‘a micro-crystalline form of quartz … a translucent substance of rather waxy lustre, presenting great variety of colours, though usually white, grey, yellow or brown’ (EBr [Note: Br EncyclopAEdia Britannica.] 11 v. 803). but the chalcedony of Pliny (HN [Note: N Historia Naturalis (Pliny).] xxxvii. 72-73) was a green stone-an inferior kind of emerald-from the copper-mines of Chalcedon in Bithynia, whence its name. Flinders Petrie (HDB [Note: DB Hastings’ Dict. of the Bible (5 vols.).] iv. 621 a) suggests that it was ‘dioptase’ or silicate of copper.
James Strahan.