Since silver by weight standard needs many works by weighing at each trade, at ginza and currency exchange, it was defined to be a piece of silver (43 momen) for giving as prize and 500 momen for trading, where it was used as "gold and silver by wrapping" that was wrapped by Japanese paper with seal.
このような秤量銀貨は取引の度に秤量するという煩雑さを伴うため、銀座および両替商で賞賜目的には銀一枚（43匁）、および商取引などには500匁毎にまとめ、和紙で包み封印をした、「包金銀」の形で取引に使用されるようになった。