Charles I promoted the opening of new gold mines, which made Hungary the largest producer of gold in Europe. The first Hungarian gold coins were minted during his reign. In the next few years, new gold mines were opened at Körmöcbánya (now Kremnica in Slovakia), Nagybánya (present-day Baia Mare in Romania) and Aranyosbánya (now Baia de Arieș in Romania). Hungarian mines yielded about 1,400 kilograms (3,100 lb) of gold around 1330, which made up more than 30% of the world's total production. The minting of gold coins began under Charles's auspices in the lands north of the Alps in Europe. His florins, which were modelled on the gold coins of Florence, were first issued in 1326.