Question to the OP: what makes you think that the private key printed on a piece of paper actually corresponds to the address printed next to it? The well-known motto in the bitcoin community states that you shouldn't blindly trust everything you see but verify it for yourself. Have you tried to verify that the private key is real and that you haven't been pranked or tricked into believing that you magically became richer overnight? One of the ways to check the genuineness of a private key is to try to spend coins from the address (transfer them to the wallet you control). Alternatively, if you don't want to get in trouble because of someone accusing you of stealing someone else's property, you can simply sign a message with a paper wallet's address and private key. This way, you will verify that the paper wallet is real and that you're not wasting your time trying to find the owner.
Good question... tbh I knew nothing about what I found on the beach and now know only a fraction more. I am a firm believer of the adage that if it sounds too good to be true, it probably is.. so in not going to be super bummed if I'm just the victim of a prank or attempted scam. I'm learning loads here and am grateful for all your input. If it turns out to be a real paper wallet,.. with real coin... great... I'll try doing what i can to find the owner.. if I've simply found someone's attempt at humour... sounds a little odd ..but ok... ya got me!! Maybe I'm wasting all your time by chasing a rediculous red herring... I don't know.. apologies if so. Maybe I shld try sweeping (.. a new word I've learnt) the coin into another account to see if it's legit.... but is that like trying the key I found in a front door even though I know full well it's not my house?