Pistole is the French name given to a Spanish gold coin in use in 1537; it was a double escudo, the gold unit. The name was also given to the Louis d'Or of Louis XIII of France, and to other European gold coins of about the value of the Spanish coin. One pistole was worth approximately ten livres.
In Dumas' The Three Musketeers, set in the 1620s, we learn that one hundred pistoles were worth a thousand livres tournois when Athos bargains for the horse he takes to the battle of La Rochelle. (GF Flammarion edition, p. 396) Since three livres were worth an écu, one hundred pistoles is worth 333.3 ecus. (One livre was also worth one franc at that time. Both terms were indifferently used since the Middle Ages. Until the middle of the 19th Century, the term "livre" was commonly used together with franc (especially to express big amounts, such as property incomes or real estate prices). As a result, the louis d'or was worth 10 livres or 10 francs.)
A coin with this name was minted in Scotland in 1701, under William II, with a weight of 106 grains (6.84g ca.) and a value of 12 scottish pounds.
The coin gave its name to the town of Trois-Pistoles, Quebec, where according to local legend, an explorer lost a goblet worth three pistoles in the river.