The piece in the ebay link from Chris may, or may not, be from the Gulf of Venice - but judging by the bidding a variety of people considered it of interest, despite the lack of obvious provenance/attribution.
In view of the overall comments from the seller, do the bidders see something I don't - is this screaming Murano, and I've missed the point. Glass with a Murano label is prolific, but signatures seem far less common.
More to the point, regret I'm unable to help the op.
