http://www.webexhibits.org/causesofcolor/9.html http://www.webexhibits.org/causesofcolor/9.html I find this article provides a better explanation (and thorough

http://www.webexhibits.org/causesofcolor/9.html http://www.webexhibits.org/causesofcolor/9.html I find this article provides a better explanation (and thorougher) of the peculiar properties of gold, and some practical manifestations of those properties.