I'll add this food for thought to this conversation. First off, it's not my place to judge someone in their decision as to whether or not they should look for the owner of a found class ring. I know what I would do, but I will keep any opinion I have to myself since it really doesn't matter.
But for you folks who say that he should try to return it, let me ask you this question. Have you ever found, say, a dog license tag? For any of us who have been detecting for any amount of time, we've all found that five or ten year old tag at the local park. So after finding it, did you take it to your local city hall and ask them to check the license number against their past records to find the name of the owner so it could be returned? I'm guessing not.
After all, why would you? It has no monetary value and it's long since expired, so it has no use. But what if that tag belonged to a dog that later died? Or belonged to a dog that had run away one day when the owner was at work? What if that tag was the only physical thing that the owner would have as a memory of their beloved pet? After all, many pet owners look at their pets as their children.
So how is finding the owner of a class ring any different? The difference is that we as the finder place a value on it based on our own opinions as to what holds value to us. We then determine if it's "worthy" of being returned to the owner or not. In the example of the dog license, for most of us it's just junk and not "valuable" enough to be given the time and effort to be returned. But that tag may have far more of an intrinsic and emotional value to the owner than any monetary value that a ring could ever have.
In the case of the ring, we are assessing a monetary value on it based on its precious metal content and we are assuming it has sentimental value to the initial owner due to the personalization aspect of it. But what if the owner didn't really want it or care about it in the first place? I was given a high school class ring by my parents during my high school years. Not once have I worn it and frankly I don't even know where it is. Maybe, just maybe, the found ring was lost due to the owner not particularly caring about it?
My point of all of this is this: if someone is going to judge another for not trying to return a found class ring, then that person needs to make sure that he or she is not a hypocrite. I'm sure folks out there will have a rebuttal to this, but this is just my opinion.