Hi, thx for reply. Im not sure about the rings i'm afraid, they look well put on, i can't see any seams or joins. the stopper is solid and the base is slopes in to the middle and the pontil has been cut into a star. I'm sure its crystal and there are odd tiny bubbles dotted about the place. I have just noticed there is number 6 on the end of the stopper and the same in the neck. cheers