Hello! I am new to this forum business so please bare with any errors... I was given this watch by my grandfather. He said it doesn’t work and he doesn’t want it anymore as he will never wear it, but it is 18ct gold and thought I could get some money for it (I work as a goldsmith). It is indeed stamped with 750 but no other hallmarks. He received it as a gift Back in the 70s I believe, when he worked for the foreign office. The watch face says ‘Léonard Geneve’ but when I opened it up to see the mechanism it says ‘Ulysse Nardin’, ‘17 jewels’ and the number ‘034688’. Can anyone help me identify if this is in fact a Ulysse Nardin watch or just the mechanism (I read that his father was called Leonard??), and any idea how much it would be worth or where I could sell it? Maybe someone on here collects them?! I haven’t been able to find any that look the same online.