Agate, a gemstone which is a compact assembly of chalcedony, that is, crystalline silica, which is constructed of thin parallel and differently colored layers which form concentric or irregular patterns. Sometimes it is also relatively monochromatic. It can be anything from transparent to opaque eg reddish-brown to brown, black colored and more.
The name comes from Achtes which is a river in Sicily. Most likely, this was once a bargain spot for agate. Today there agaterna in Brazil, India, Egypt, Scotland, Uruguay and Finland.
