1765 EM Russian Empire 5 Kopeks Copper Coin- C#59.3.  This large coin has a weight of app. 51.2grams and a diameter of 42mm, and was minted at the Ekaterinburg Mint, thus the EM on the coin.  The obverse of the coin is of the crowned monogram of Ekaterina II and the reverse of the double headed eagle.  This particular coin was only minted in the years 1763-1796 and has an unusual reticulated edge to it.  Thanks for looking!