This article focuses on the fine silver and gold trade coinages of the mint of Florence in the thirteenth century. It summarises the early silver grossi from the 1230s and raises questions about the existing classification while drawing attention to aspects that require further study. It also traces the spread of the city’s gold florin, introduced in 1252, as an actual coin, the benchmark for other gold coins, the basis for an ‘international’ money of account and the model for many imitation florins. It stresses the importance of the florin in the economic development of Florence and in the so-called commercial revolution of the Middle Ages.