Hi, It appears to be a Civil War EM buckle worn by the Northern Army. It has all the proper bells and whistles. Some of these buckles are getting up there in value. Unfortunately, I don't have much expert knowledge, I've just been around over 60 years and held many of these in my time. Good ones and bad. This one looks right to me. Good Luck. These ARE getting hard to find. Hope this helps a little. Peace, Mark