Besides trade in the precious metals gold and silver Frankfurt Jews also dealt in other metals such as iron, steel, tinn, copper, lead and brass. In the early modern era these metals had different applications in some ways to their present ones. Tin, for example, was an important raw material for the production of tableware until the end of the 18th century. In the 16th century the Frankfurt city council was heavily involved (at times with heavy losses) in mining for and processing ores. At the end of the 17th century the Jews also became increasingly involved in these activities. The visitation lists for 1694 show three dealers in copper and tin, and in 1732 the Landgrave of Hessen gave his court factor Baer Loeb Isaak zur Kanne the right to operate his copper mine. The Christian authorities nevertheless tried to control Jewish trade in metals. The residence code of 1616 requires Jews selling metal weighing more than a 12.5 kilograms to have it weighed on the public city scales.