United States dollar

The history of the dollar in North America pre-dates US independence. Even before the Declaration of Independence, the Continental Congress had authorized the issuance of dollar denominated coins and currency, since the term 'dollar' was in common usage referring to Spanish colonial 8 real coins or "Spanish Milled Dollars". Though several monetary systems were proposed for the early republic, the dollar was approved by Congress in a largely symbolic resolution on 8 August 1786. After passage of the Constitution was secured, the government turned its attention to monetary issues again in the early 1790s under the leadership of Alexander Hamilton, the secretary of the treasury at the time. Congress acted on Hamilton's recommendations in the Coinage Act of 1792, which established the Dollar as the basic unit of account for the United States. The word "dollar" is derived from Low Saxon "daler", an abbreviation of "Joachimsdaler" – (coin) from Joachimsthal (St. Joachim's Valley, now Jáchymov, Bohemia, then part of the Holy Roman Empire, now part of the Czech Republic; for further history of the name, see dollar.) – so called because it was minted from 1519 onwards using silver extracted from a mine which had opened in 1516 near Joachimstal, a town in the Ore Mountains of northwestern Bohemia. The term "dollar" was widely used in reference to a Spanish coin at the time it was adopted by the United States.
Until 1874 the value of the United States dollar was tied to and backed by silver, gold, or both. From 1792 to 1873, the U.S. dollar was freely backed by both gold and silver at a ratio of 15:1 under a system known as bimetallism. In this system, the dollar could be exchanged for 371.25 grains (24.06 g) of silver or 24.75 grains (1.60 g) of gold.