Hi Ruth
Lovely item - I posted a basket a few days ago
http://hometown.aol.co.uk/blackcatgla/images/murano%20basket%20copy.jpg - have not had much feedback on it but I think the colour and surface pattern on your bowl are similar enough for a Murano ID on yours, manufacturer may take longer (as you see my basket has been termed generic and it has a Murano label!)
Although mine is a line in as it were, I feel your bowl is of a higher quality - I am interested in the gilt, is it simply worn from the foot or is it a brushed effect, also is there some aventurine in the bowl, at the top rim, or is it a reflection from the base?
What is the base like, polished, broken pontil, concave pontil, etc?
Hope you get some interest in this item - I will take a look through my different sources
Ruth recent post
http://www.glassmessages.com/index.php/topic,2544.0.html tell me that your bowl is very likey by Seguso of Murano late 1950s
Also Ruth your pontil looks polished concave - broken would be snapped of at the surface and left rough
Adam D555