Usually "Coats of Arms" has animals or plants, trees, crown, ect. that are very distinctive, that would pertain to the family. I don't see any of that here. I see a lot of very nice workmanship. I agree with Jeweler. I don't see a Coat of Arms here. That arch across the back of it, that has a notch in it. Are those letters, or possible makers mark? With it being notched out like that, it looks like it should be hanging on a wall. It may be just a small decorative frame, that you would put a picture of a loved one in the middle of it.