Thanks for the info, I didn't know back in the 19th century that the US also used bimetallic currency where 10 US silver dollar is equivalent to 1 gold coin. T

Thanks for the info, I didn't know back in the 19th century that the US also used bimetallic currency where 10 US silver dollar is equivalent to 1 gold coin. This has been (more or less) the standard since like forever, for at least several thousand of years including in major world's empires including the Greek, Persian, Roman (Rome and Byzantine), Islamic (Rashidun, Umayyad, Abbasid, Ottoman) and British Empire until 19th century where bimetallic currency namely silver coin (dirham) and gold coin (dinar) were pervasive. Fun facts, the word dirham in Islamic empire is derived from the word drachma with the same meaning in Greek, while dinar is derived from the Roman word denarius.