In a thread up yesterday on the US Mint’s decision to issue a new (as yet undesigned) nickle, the linked article mentioned that the Mint removes used nickles from circulation that are older than XX number of years. A quick search couldn’t find the thread but I think it was about 25 or 30 years or so. This came as a surprise to me as I’d always just figured that collectors gradually gleaned these out as they became older.
What I’m curious about is how does the Mint seperate coins that meet their age requirement from those that don’t? Is this seemingly monumental task actually carried out by hand as countless individuals come across them or do they have actual machines that can rapidly scan through the coins, nickles in this case, and read the dates, small as they are?
Also, at what level/by who is this task performed? By banks?