You're getting hosed, homeboy. The traditional 10 year gift is aluminum or tin. That diamond thing is a recent cash grab by the inventors of such brilliant ideas as Sweetest Day and the like.
Oh, don't worry, the band is made of tin and the "diamonds" are a painted aluminum alloy. She'll never know.
I thought about this too. Here's my conjecture: the librarians are only archiving what people do, not suggesting what they should do. They probably see in periodicals and the like what trends are now being observed, and they are studiously documenting. That, or some enterprising librarian whose 10th anniversary was approaching is pulling a fast one on her husband.
I appreciate you giving librarians the benefit of the doubt. Who ever heard about librarians on the take. On the other hand, the fictional librarian Lillian of Hubskina is sending a bunch of Heros of Hubski to Tidder -- she's probably on the take. Don't trust her. eightbitsamurai