As wine is essential for the church rituals, monasteries had their own vineyards which were frequently mentioned in the charters. In the Law on mines, issued by despot Stefan Lazarević and dealing with the town of Novo Brdo, a tribute called "psunja" was to be collected for each wine brought to the city square to be sold. Only wine produced in the city metochion was freed from taxes and, apart from money collecting, the tribute served as a protective measure for the domicile wine production. Some of the even older wine provisions by emperor Dušan can be considered as the origins of the geographical indication, while mixing of wine and water was strictly forbidden.