Tintype of a Civil War soldier

In black thermoplastic case with brass hinges and red velvet liner; Preserver and mat: brass decorated with eagle, 2 American flags, cannon, and E Pluribus Unum set in a red velvet liner; tintype with cover glass of an African American Union soldier with a moustache and beard, holding a pistol across his chest. His buttons and belt buckle are hand-colored in gold paint. The hand-coloring on the buckle reads backwards "SU," which when considered that the image is reversed, reads "US," the traditional inscription on Union Civil War belt buckles.