looking for some info on the (trade mark)..under the date 1798...which is stamped half on and off the coin..or any thing else on it.. .......tar.....
I suspect one is a mint mark and the other a privy mark. Unfortunately I don't have my books with me to look it up. I will when I get home if you don't get an answer first.
Sorry - I forgot all about looking this up for you It appears to be E M - the mint mark for St. Petersburg.
I can't make out the mint mark on your coin. However, EM is the mintmark for Ekaterinaburg http://russiancoinworld.homestead.com/files/MintMark.htm
Yes,it is the E.M. mintmark of the Ekaterinburg mint.The monogram is that of Czar Paul I (ruled 1796-1801). Aidan.