A ducal denarius in a very rare variety - a large horseman's head and no mark in the field.
The appearance of the surface is not objectionable, also there is no doubt that it was minted this way.
A very nice piece.
Obverse: prince on horseback to the left, no mint marks in the field.
Reverse: head in a pearl border, in the outer border the legend BOLEZLAVS.
Silver, diameter 15 mm, weight 0.54 g.