Natural green chalcedony for agate 925 silver ring

Product Description

Chalcedony /klˈsɛdəni/ is a cryptocrystalline form of silica, composed of very fine intergrowths of the minerals quartz and moganite.[2] These are both silica minerals, but they differ in that quartz has a trigonal crystal structure, while moganite is monoclinic. Chalcedony's standard chemical structure (based on the chemical structure of quartz) is SiO2 (silicon dioxide).

Chalcedony has a waxy luster, and may be semitransparent or translucent. It can assume a wide range of colors, but those most commonly seen are white to gray, grayish-blue or a shade of brown ranging from pale to nearly black.

The name chalcedony comes from the Latin chalcedonius (alternatively spelled calchedonius). The name appears first in Pliny the Elder's Naturalis Historia as a term for a translucid kind of Jaspis.[3] The name is probably derived from the town Chalcedon in Asia Minor.[4] A little later the Greek word khalkeappears in the Book of Revelation (Apc *1,*9). It is a Hapax legomenon, a word found nowhere else, so it is impossible to tell whether the precious gem mentioned in the Bible is the same mineral known by this name today