If you want to (eventually) claim something as yours you first have to take it to the copshop, tell them you found it (and details of where and when) and that you think it is abandoned or stolen or whatever. They take it onto evidence to allow the time (pretty sure it was either 6 or 12 weeks) for the original owner to report it stolen and come and claim it. Then you will get a call saying you can come and get it (with a clear conscience).
Had to go through the whole rigmarole when my brother found a bag of about 120 diamonds in Hatton Garden. He emigrated to NZ and left them with me to take to the police. took them to Islington cop shop. waited 6 weeks (or whatever) and then went and collected them.
In regards to the 'evidence' question.
If you want to (eventually) claim something as yours you first have to take it to the copshop, tell them you found it (and details of where and when) and that you think it is abandoned or stolen or whatever. They take it onto evidence to allow the time (pretty sure it was either 6 or 12 weeks) for the original owner to report it stolen and come and claim it. Then you will get a call saying you can come and get it (with a clear conscience).
Had to go through the whole rigmarole when my brother found a bag of about 120 diamonds in Hatton Garden. He emigrated to NZ and left them with me to take to the police. took them to Islington cop shop. waited 6 weeks (or whatever) and then went and collected them.