The Wiardunek was a medieval central European unit of mass most widely used in Poland and Germany. Wiardunek was also used as a unit of account and as a such as money.
As unit of mass: 1 wiardunek (c.49 g) = 1/4 grzywna 1 wiardunek = 4 ounces
In the 14th century, wiardunek took on the role of a unit of account of coin. As such 1 wiardunek was equal to 12 groschen