A nice piece.
Variety with a bust with a large head.
Obverse: denomination III between lilies, below it the coat of arms of Riga, separating the dates 15-86 and the beginning of the legend GR-OS, below it further 3 lines of the legend with punctuation in the form of rhombuses:
ARG-TRIP/CIVI-RI-/+GE+;
Reverse: crowned royal bust with numerous jewels in the rim of the crown, wearing plate armor, to the right, in the rim a legend with punctuation in the form of rhombuses:
STEP-D-G-REX-P-D-L-;