Thank you both so much for your replies which seem to confirm the bowl is made in Venice. I've looked at both links and, due to weight and thickness of bowl I think it's probably an older piece? I've now looked at images on your links and it appears Galliano Ferro, who moved from AVeM also made these bowls so still not completely sure of maker? Does anyone have an approximate idea of value now that location of makers is known?
Many thanks