The coins introduced by the Postal Savings Credit Card Center are nothing more than "several banknotes with the same number and a collection book". These things are difficult to add value, because they are all selected from the issued coins. Ordinary coins with the same last few digits in the book are not really rare currencies, and then they are sold at high prices, and no one cares after buying them. Isn't this a waste of money? This suggestion was ignored. Banks with great historical significance can generally buy coins: for example, Hong Kong and Macao recycle commemorative coins and so on. )