A nice piece.
Variety with the endings of legends L/LI.
Obverse: in the pearl rim crowned monogram SA, on its sides the date 15-6Z, in the outer rim the legend divided by three leaves:
SIGIS AVG REX PO MAG DVX L;
Reverse: in a pearl rim punctuated by Gediminas' Pillars of Pogon to the left, in the outer rim a legend punctuated by tri-lobes:
GROSS AR TRI-MAG DVCA LI;