Coins of this type with the dual denomination was produced from 1833 to 1841 at the two mints - Warsaw and St. PETERSBURG (different letters - "НГ"or "MW". In 1833 produced only in St. PETERSBURG. Coins 1835-1837 years with letters "НГ"there are high and low eagle and 1837 "MW"- with wide and narrow tail.
After the war with Napoleon was held at the Congress of Vienna, which decided the question of state borders in Europe. To the Russian Empire
ceded the Duchy of Warsaw - the main part of Poland, repeatedly shared with 1772 between Prussia, Austria and Russia. In 1816, at the Warsaw mint began minting copper, silver and gold coins with inscriptions in Polish, which lasted until 1850. Included two types of coins. Later they were replaced by nationwide, which was used before the independence of Poland in 1918.
The picture shows a copy from the exposition of the State Hermitage with the number IT-R-2-12155.