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.
The most common form of goldstone gives the illusion of being reddish-brown, although in fact that color comes
from the copper crystals and the glass itself is colorless. Some goldstone variants have an intensely-colored glass matrix—usually
blue or violet, more rarely green—and a more silvery appearance to the suspended crystals, whose color may be partially
masked by the glass or which may be based on different metals than copper, possibly cobalt, manganese, or chromium.
