If it's a small amount of cash ( < $100 ) and there's absolutely no way to find the owner, then I don't see where the harm is in keeping it.
Anything larger than that is probably worth hanging on to for a while, but keeping your eyes open for anyone looking for it.
If there's a way of positively identifying the rightful owner, no matter the amount, giving it back is the moral thing to do.
Anything larger than that is probably worth hanging on to for a while, but keeping your eyes open for anyone looking for it.
If there's a way of positively identifying the rightful owner, no matter the amount, giving it back is the moral thing to do.