[thaumasiotes]

Wikipedia would have told you.

A cumal is the unit in which medieval Irish monetary values are denominated. It is also the medieval Irish term for a female slave; the unit is notionally equal to the value of one such.

The point of answering the question in a historical currency is to emphasize that this question is easy to answer by simply thinking "what have been some well-known historical currencies?"

People trade in materials, tools, food, livestock, and women.