A beautiful piece.
A nondescript Iger bust variant with a crown topped with a royal apple.
Obverse: denomination +III+, below it the coat of arms of Riga, separating the date 15-91 and the beginning of the legend GR-OS, below it further 3 lines of the legend ending with a lily:
ARG+TRIP/CIVI+RI/+GE;
Reverse: crowned royal bust with numerous jewels in the rim of the crown, wearing armor, with a tubular orifice seen from the side, to the right, in the rim the legend:
SIG+III+D:G+REX+PO+D+LI;