The reason I think it is a belt buckle is that the width matches up with frame belt buckles. The first attachment shows a Georgia frame buckle on top of the mystery buckle. The second attachment shows a forked tongue buckle, a Georgia frame buckle, and the mystery buckle. The buckle has almost the exact dimensions as the Georgia frame and is only slightly narrower than the forked tongue. I'm still not positive that it is a belt buckle and am not sure whether it is Civil War vintage. I hope there is an expert out there than can make a positive ID one way or the other.