Is there any way that you can post a link to a picture?
How large are the letters? Are they written like a monogram, or as
seperate symbols? Are they boxed in, in the style of a hallmark, or
open, in the style of engraved initials? Which country are you
writing from, and which country do you think the rings are from? Are
there any other letters, numbers or symbols? Do they look hand
engraved, machine engraved, or stamped in?
Sorry to answer a question with a question (or several).