1/4 Plate Ambrotype of a Civil War Soldier

This 1/4 plate ambrotype of a Civil War Soldier has left me with more questions then answers. This soldier appears to be wearing a Federal Frock or a Confederate Frock. The green cuffing fits a similar example of a ID’ed Confederate out of Virginia. The pattern looks very similar to a Federal frock and the blue could have turned more green over a hundred fifty plus years. Overall still a beautiful image with the soldier holding a hankie in his jacket.