The following is the only one of these I have ever come across. It was originally an Eagle Breastplate carried by a soldier in the Civil War. This plate was either badly damaged in battle or discarded after it broke. Chances are it came from a Union firepit. Actually it is not really an eagle breastplate. It is the lead backing of the breastplate that burned free of the plate from the intense heat of the firepit. The heat burned an impression of the eagle in the lead and this is what was found. Not a perfect impression but the eagle is clearly evident. It still even has one loop left. An unusual and pretty rare item to find.