imagine purchasing some pretty marbles at sale a while back then on closer inspection you realize that marbles dont have brilliance to this degree. I was amazed. Still am. I know what you're going to say. I didn't ask for this. What good is something when no would even pay it any mind as to not be possible.
Theres all sorts of iridescent glass coatings and fuming........ I don't see what you are getting at. look up fredrick carder for examples of all sorts of shiny lustrous glass.