The most common idea is it was a matchbox cover. It may be, but there is no clasp or way to secure a box in it. The edges are rolled to the inside so there is a lip around the edges. It may be that it is missing a part, but again, with the rolled edge, I'm not sure. The last shot is the inside it. The coating is sort of like an enamel, but is thick.
Any ideas, comments, guesses, interpretations, etc. would be most appreciated!















