Goldstone would be the original aventurine.
The mineral known as aventurine was named after the glass.
Sometimes the sparkle is intentional. Sometimes it isn't. People have intentionally overloaded art glass with the chemicals it takes to make the sparkle. I would have thought that the aventurine we see in marbles from the 1930's through 1970's was accidental but I am not sure. Jabo had it intentionally in the last few years but I think they got the aventurine premade from art glass suppliers, as opposed to mixing the chemicals from batch and getting the sparkle that way.
Much ... but I don't think all ... aventurine is copper based.
Here is a patent filed in 1947 which is about making green colored glass. http://www.google.co...id=abprAAAAEBAJ
They mention an aventurine which appears to be chromium based, not copper. I think this patent is more interested in suppressing the aventurine but it notes that sometimes it is made on purpose.