Other than knowing that goldstone is created by the precipitation of copper in glass, the process is a fairly guarded secret. It is known that the process is a slow one, and must be created in small batches, hence why it is more valuable than many other glass beads. There are several varieties of goldstone to be found, based on color. The most common is the reddish-brown goldstone, which gets its color from the copper – the glass itself has no color. Another type is the blue/purple color, which does have colored glass to give the blue and purple colors, with sparkles that take on a silver color. The rarest is the green goldstone, which is made with a dark green colored glass and has light green sparkles.
Goldstone comes in several colors: reddish brown (most common), blue, purple, and green (rarest).
Since the actual process of creating goldstone has been kept pretty secret, there is some debate as to how it was initially created. Some say it was discovered in Venice, Italy by the Miotti family, and has since continued to be a desirable element in jewelry work. Myth has it that Italian monks accidentally discovered it centuries ago. It is said that while working on creating glass windows, copper shavings were spilled into the vat of glass. At first they thought the batch was ruined, but the result was this beautiful sparking glass instead! (Sadly, someone has decided to scam people using this myth in conjunction with the misinformation that goldstone is a natural stone, by setting up a “tour” of an old monastery in Italy where people can go in and pick pieces of goldstone up off the ground!)
Goldstone can be manipulated much like natural stone, creating chips, beads, and figures.
If there's a stone you would like to know more about - drop me a line! Have a mystery stone? Feel free to post a comment about it, including a link to a picture, and it could be featured on this blog!
Chemical composition: Glass and Copper (SiO2 with Cu)
Color: reddish brown (most common), blue, purple, green (rarest)
Wikipedia – Goldstone. http://en.wikipedia.org/wiki/Aventurine_glass
Lapidary Digest. http://www.gemcutters.org/LDA/Archive/html%20files/LD029.htm