Florin (front)
Florin (back)

Florence was a major banking center during Chaucer's lifetime. Many Florentine banks were international supercompanies with branches across the Continent. Above are the front and back sides of the florin, a coin (forged by Florentine goldsmiths) that often served as common currency all over Europe.

In 1344, Edward III introduced into England a number of new coins, including his own gold florin and the gold noble.
If you are so moved, you can also view a coin used in Spain in Chaucer's day.

Dante and Florence

This painting above (by Domenico di Michelino, 1465) depicts the poet Dante gazing toward Florence (the walled city on the right). The painting is in the Duomo (Cathedral) in Florence.