Louis d'or

The Louis d'or [lwi dɔʁ] is any number of French coins first introduced by Louis XIII in 1640. The name derives from the depiction of the portrait of King Louis on one side of the coin; the French royal coat of arms is on the reverse. The coin was replaced by the French franc at the time of the revolution and later the similarly valued Napoleon. The actual value of the coins fluctuated according to monetary and fiscal policy (see livre tournois), but in 1726 the value was stabilized.

The 1640 issue of Louis d’or contained five denominations: a half Louis and a one, two, four, and eight Louis. All subsequent issues through 1793 were only denominated in half, one, and two Louis.

The Louis d'or (a gold coin) replaced the franc which had been in circulation (in theory) since John II of France. In actual practice the principal gold coin circulating in France in the earlier 17th century had been Spanish: the 6.7-gram double escudo or "doubloon", of which the Louis d'or was an explicit copy. There also existed a half-Louis coin (the demi-louis d'or) and a two-Louis coin (the double louis d'or).

The Louis d'or fixed several problems with previous French gold coinage. Louis XIII previously struck coins from 23 carat gold even though Charles V had made 22 carats the de facto international standard for gold coinage a century earlier. Royal edicts had set the official values of his gold coins so low that it was profitable to export them. Since they were still made by hand, cheaters could shave bits of gold from the edges of the coins before passing them on, an illegal process called clipping. To fix this, Jean Varin, a medalist from Liège, installed machinery in the Paris mint which made perfectly round coins so that clipping could not go undetected. The new demi Louis d'or maintained the weight of the old écu d’or, but decreasing its fineness to 22 carats, allowing it to circulate at a value of five livres. Its double, the Louis d'or had the weight and fineness of the Spanish pistole, or two escudo coins, which was an international trade currency.

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