I think that it was made by Andrea Tagliapietra (or by somebody of his team). He works with Alessandrite glass very often, also if now his main production is Calcedonia glass. The signature is horrible, but this is not a very important detail, due to their signature policy is not sticht at all. The signature style depends due to quantity of wine they have in their blood...
Anyway I see a similar calligraphy.
Also the son, Fabio, works with the same style of glassworks and the calligraphy is similar too. So he is a possibility, but the final "touch" says the father Andrea.
I can't tell you that I'm sure at 100%, but at 90% this is the right guy.