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Very nice bracelet. It?s Italian hallmarked for 18karat gold (750) and the hallmark is of the style used between 1944-1968. The assay office was Vicenza (VI).
The number against the ?VI? is the registration number of the jeweller. It looks like ?175? although I can?t be certain that it?s not ?75? from your picture. I?m not sure if what I see as the first digit is just the edge of the cartouche, but you may have a better view in hand.
If it is 175 then it?s by F. LLI RANZAN ROMEO & MARIO S.n.c. from the town of Monticello Conte Otto, in operation between 1954-1971
If it?s 75 then it?s by STEFANI AMEDEO di Alessandro of Vicenza, in operation between 1950 and sometime between 1955 and 1971.
In either case, the hallmark is not later than 1968.