In the history of economic thought, monetary theories in the Germanspeaking world of the early modern era are considered backward compared to the approaches in other European countries. This backwardness can be illustrated by two authors from the mid-18th century who were not only contemporaries but also successively in the service of Frederick II (“the Great”) of Prussia. The first is Johann Philipp Graumann, one of the 'projectors' of the 18th century. As master of the mints in Prussia, he developed a coin project, where he tried to implement a new monetary standard to promote trade, generate seigniorage income and implement the Prussian coins as a kind of a reserve currency. In his writings, he developed a typical mercantilistic monetary theory with a clear understanding of the mechanism in the balance of payments. But even when he tried to include credit instruments, he did not take banks or broader financial markets into account. The second thinker is Johann Heinrich Gottlob Justi, who took the opposite position concerning the coin project as well as in his theory. He defended a strictly metalistic monetary approach where the value of money is only based on the metal's value. While Graumann rejected the English coin system, Justi recommended its laws for countries without their own mines, because the sovereign should not misuse his right of coinage. For him, the monetary system had tobe reliable and stable to serve trade and economic development.