The story behind this set of large round brass tags is unknown but certainly curious. We originally thought that they may have been used to house hotel keys, but the person we bought them from said that they were found in an old coal mining town in Pennsylvania. After some research, we found that miners used to attach a brass tag with their ID number to the cart they filled, which was then pulled up to the top of the mine to be weighed (miners were paid by the ton). Awesome! This set of brass tags is in unrestored vintage condition. Each tag measures 3" in diameter.