Hi Ivo, I'm intrigued to know your reason. This could help me narrow down, during my currently ongoing investigations. Have you seen anything similar? You mentioned that it maybe relatively recent. I'm not too sure of that, as the base does have clear signs of genuine ware, like other pieces I do have that has age and has been confirmed. Please note, this is not in anyway to underminding your expertize on glass, but however, to provide you with as much detail as possibly. Christine seems to think otherwise and It would be interesting to see what her thoughts are now, that is, since your comment.