This is a portrait of Abraham Lincoln on a steel "canvas" or base.
I do not know the medium, but it appears to be a type of paint on the steel. There are some small spots where the medium has come off, revealing thickness of the medium typical of paint, perhaps oil.
I am not absolutely certain it is a true painting. Perhaps it is photograph of a painting exposed onto a thick emulsion that had been applied to the metal base, but I think it is a painting.
It is overall a rectangle with a sunken oval wherein the portrait exists. The rectangle measures 20 1/4" by 24 1/4 " and the oval measures 19" in height and 15" in width.
The area of the rectangle around the oval has been hand painted in gilt, leaving a space at the bottom like an arched banner for the caption, which reads in sharp block lettering: WITH MALICE TOWARD NONE, WITH CHARITY FOR ALL.
The metal base appears to have been painted black originally, at least at the edges, for those are black. The upper right section of the edge shows rust, as in some small spots elsewhere on the edge. The very back of the piece shows a fair amount of surface rust. The rust at upper right extends a little bit into the gilted area but nowhere near the portrait area.
On Lincoln's shirt front, between the lapels, are two small spills of gray paint, apparently enamel. These are newer and must have been spilled in more recent years.
There appears to be no signature, but if there is, it must be under the gilting, which was definitely applied by hand after the caption lettering was in place.
This piece is in overall good condition except for the areas described. I have attached two photographs, one of the whole item, and one a closeup of a small damage area where the medium has come off.
I seem to have read or heard that pieces like this used to hang in old schools and/or post offices or government buildings, but I do not know this for sure.
I hope this is enough information to learn more of the possible general history and possible value of this item.