The production of precious metals in the Balkans reached its climax in the 15th century. It was exported mostly by Ragusa, basically for the Venice Mint. According to the available documents it can be estimated that the traffic of such metals carried out via Ragusa was between 11060 kg in 1425, and an optimum estimation of 25 tons annually for the first half of the century. The Ottoman occupation of Serbia and Bosnia in the middle of the century marks the end of the exportation of raw materials indispensable to the European monetary economy, which lacked precious metals for mints. The production as well as the coining of the Balkan precious metals took place within the closed circuit of the Ottoman economic autarchy. Notwithstanding all the efforts of the central administration, including a highly developed legislation, and in spite of the development of a big mining centre of Siderokapsia (Eastern Macedonia), the production of precious metals continued to decline in the 15th century. This economic phenomenon led to the financial crash that marked the beginning of the recurring financial and economic crises in the Ottoman Empire at the end of the 16th century. The contribution of the precious metals from the Balkans to the European monetary economy at the end of the Middle Ages has not been sufficiently studied by the specialists in economic history, and it has not been taken into account regarding the spectacular decline of the Ottoman economy and power.