I apologize for using the sellers pictures and will happily post my own when it gets here.
I've looked at the auction and pictures over and over and over again and I do not doubt it is glass. The seller is a professional with a spotless reputation and made a point of the fact that the vase is glass...twice (as it does not look like glass in the photos). I also have seen a lot of signatures in glass and this signature would make no sense on a pottery piece. Looks to be diamond point.
I've been researching like one possessed and have found a tie between Luciano Minguzzi the Italian sculptor and Ermanno Nason the glass artist and IVR Mazzega, it looks as though Nason while working for Mazzega did some collaborative pieces with artists including Picasso and many other highly respected artists.
I do realize this would an an outside chance at best but one I would hope to get a absolutely with out a doubt not possible from the experts here so that I can just appreciate a pretty vase and not hope for more than it is.
Thank you, Kelly