United States, copper Braided Hair large cent, 1852

Are the letters incuse (sunk into the surface of the coin)? If so, it sounds like you have some countermarks there. They are quite commonly found on large cents, and were put there by a number of businesses and individuals in the 19th century. This was for a variety of reasons; sometimes for advertising purposes, or sometime personalization, like someone’s initials. From the sounds of it, I’ll bet that’s what you have.