This is a mule struck in Great Britain (see the letter Z in the signature of Droz, taller than other letters).The obverse is the standard portrait of Napoleon by Droz in 1806. According to Bramsen, these dies were purloined by foreign troops during the occupation of Paris in 1814. For more information, read the articles: "Standard 40 millimeter obverses" and "The last twelve medals" by David Block (Fortiter).