My employer briefly had a contract to service Coinstar machines, and one time I was dispatched for that duty. I was instructed to discard anything in the divert tray of rejected coins. Most of it was severely damaged coins or foreign coins, but I did find three pre-64 silver Canadian dimes! Not sure if I may have missed more before I thought to start looking at what I was throwing out. Sadly, I only got that one opportunity to search for that particular treasure, but it made for an interesting addition to my small stack.