Goldstone is a type of glass made with copper or copper salts in the presence of a reducing flame. Under normal oxidative conditions, copper ions meld into the silica to produce transparent bluish-green glass; when the reduced goldstone melt cools, the copper remains in atomic isolation and precipitates into small crystalline clusters. The finished product can take a smooth polish and be carved into beads, figurines, or other artifacts suitable for semiprecious stone, and in fact goldstone is often mistaken or misrepresented as a natural material.