A very nice piece.
Obverse: head of Alexander I to the right, in the rim legend:
*ALEXANDER I.CES-ROS-RESURRECTOR-KING-POLS-1815;
Reverse: in an oak wreath: 2/ZŁO-POL/1830, under the wreath initials F-H-, in the rim legend:
MIKOŁAY I.CES-WSZ-ROSSYI THE REIGNING KING OF POLAND