I found this today about a foot down. It has a decorative pattern all over it and a round recess. It looks like the top to a chest or maybe it's a piece to an old stove. I don't know.
I am certainly no expert, but a chest entirely of metal would have been heavy to carry around. A stationary appliance like stove makes more sense to me. But if it's a treasure chest, go back and find the rest!