Fiorino d'oro (florin)
13th–14th century ・ gold ・ 13th century ・ Florence
Born in 1252, about 3.5 grams and nearly pure gold, it held its standard for close to three centuries. The city's lily on one face, John the Baptist on the other; a king's face nowhere. By turning changelessness itself into supreme credit, this coin became Europe's anchor without any state behind it.