Svazzo, I also favored Seguso. I had a heavy sculptural bowl that had the same color and gold, though the form was very different. My bowl did not have a label, but looked like Seguso. This bowl reminded me of that bowl.
I read some good online advice from a Venini expert a while back. I don't remember who it was right now. He was writing about fazzoletti, but his advice is probably good for all forms of Murano. If a Venini piece has no trace of a signature, it should just be considered general Murano when it comes to price. Many of the forms are so easily reproduced that without a signature, the source is uncertain.