Chalcedony

Pronunciation

• IPA: /kælˈsÉ›dÉ™ni/

Noun

1. A form of fine-grained quartz that is nearly transparent or has a milky translucence; it fractures conchoidally.
• 2012-03, Lee A. Groat, Gemstones, Although there are dozens of different types of gems, among the best known and most important are … . (Common gem materials not addressed in this article include amber, amethyst, chalcedony, garnet, lazurite, malachite, opals, peridot, rhodonite, spinel, tourmaline, turquoise and zircon.)