Poland under Russia, Nicholas I, 1-1/2 rouble=10 zloty 1835 НГ Petersburg

Nicely preserved details. Mechanical manipulations.

Obverse: eagle of the Empire, at its tail the initials НГ, in the outer rim the legend:

ЧИСТАГО СЕРЕБРА 6 ЗОЛОТНИКОВЪ 31 1/2 ДОЛЕЙ;

Reverse: in laurel and oak wreath inscription:
1 1/2/РУБЛЯ./10/ZLOT-/1835;