The portrait is of a Big Mountain Indian from the Black Mesa area near Four Corners, probably in northern Arizona.
The work is done with sumi-e inks, the medium used in many Asian paintings, and is on acid-free paper. It is surrounded by acid-free material, so it may last a thousand years, since some of the oldest paintings still in existence were done on acid-free paper.
The portrait has a rich mahogany frame and is covered with ultraviolet light resistant glass.
By the way, the frame is rectangular. Only my photo of it isn squared up.