I've been thinking about this piece for a couple of days. I guess I have some concerns about a Barovier and Toso attribution for it, although I'm a reluctant to dampen everyone's enthusiasm.
My first reaction on seeing the piece was, "Is this really 'Zebrati'?" The main source of my doubt is the lattimo line that leads to to the 'Zebrati' attribution. It just looks too white and too defined compared to what I expect from 'Zebrati.' Also, it looked to me like rough pontil, although Craig makes a good case for it being an impact fracture. So I went to look for 'Zebrati' in books. Pina has one on page 33 which has broad, dark stripes. She correctly states that the technique was developed by B & T in 1949 (confirmed in Ricke 'Italian Glass'). But I couldn't find any pictures in any of the other art glass books I have, including Marina Barovier's 'Barovier.' There are plenty examples on eBay, the common element being a thread of varying colour round the piece. Googling adds some auctions, but none of them I saw gave references for their attributions, and no piece had a label or was marked "Barovier and Toso."
So, given the fact there are many pieces called 'Zebrati' out there, and the lack of well documented examples, particularly in the high end books, I wonder if 'Zebrati' has become another Cordonato Oro. By that I mean that the name was originally used by B & T as a propriety name, which they applied to high end glass, but the term is now used more generically to describe any piece of glass with lines on it produced by anyone in Murano. We know that commercially successful techniques were copied by other furnaces., Cordonato Oro being a prime example. However, that doesn't mean that any piece that looks like 'Zebrati' was made by Barovier and Toso.
I'm not saying that this pieces isn't Murano, or that it isn't well made. I just wonder if it's Barovier and Toso. Fundamentally, that won't affect anyone's appreciation of it, although it would affect resell value.
Barovier and Toso are still very active in Murano and maintain an excellent museum of their products. I wonder if an email to them with a photograph would clarify matters. Or does anyone have a photograph or a definition of what 'Zebrati' should look like?