This is a key hole cover for a door. Very likely, on the other side of the door was a full back plate and door knob of this pattern. On the back side of the door, owners often had a door knob and rosette, with a key hole cover under the knob.
This is a stamped flashed copper cover with a Victorian pattern. The cover is steel but it has had a copper coating and black flashing. We have cleaned it lightly, but it maintains its aged patina.
The cover measures 2 1/2 inches vertically and 1 3/8 inches wide. We will include screws.