A very rare tymph.
Tymfs minted in Lviv are characterized by a large royal monogram. However, it is not the only one used by the engravers of this mint. It is very rare to find tymphes with all Lviv features, but with a small monogram, as on the present piece.
The reverse with ornaments on the sides of the POL, a date typeface characteristic of Lviv issues.