Firmin René Desloge (17 February 1803, in Nantes, France – 20 July 1856, in Potosi, Missouri) was a U.S. businessman who founded lead mines and other mercantile businesses.

[3] Firmin followed in 1823, and was introduced by his uncle and Audubon to the businesses of fur trading and mercantile interests along the Ohio and Mississippi rivers[4] and lead smelting and mining in Potosi, Missouri.

[5] St. Genevieve, a Mississippi River town populated largely by French immigrants and their descendants, was a hub for trading with Indians and new white arrivals to the frontier.

[10]His son, Firmin Vincent Desloge, expanded the family mining and mercantile operations,[1] becoming one of the richest men in the world at his death in 1929.

His uncle (by marriage to his father's sister Marie-Marguerite) was Jean-Baptiste Sollier de la Quillerie, a member of the French king's gendarme.