Vietnam - Tu Duc (1848-1883) - Quan nd. (KM.502; BNF suppl. 504; Schr.340) - Obv: Tu Duc niên tạo / Rev: Già Tien nhất quán - 5.33 g. - a.XF, the beginning of the melting of this type of ingots is not known, but they are mentioned for the first time in the 4th moon of the 15th year (1862)