Based on the Gresham's law, however, the amount of mintage of koban, which was good money, was decreased and nominal coins such as Nishu kin gold and ichibu-gin silver coins, which were bad money, prevailed in the market, so a great amount of premium was demanded for an exchange of ichibu-gin coins into koban.
しかし、グレシャムの法則が働き良貨である小判の鋳造量は衰退し、市場では悪貨である二朱金および一分銀のような名目貨幣が凌駕するような状態であったため、一分銀から小判への両替には大幅な増歩が要求された。