There are no marks on the back of this to indicate it was a wall hanging, so it may have been a panel design on a chest. The metal piece measures about 7" x 3 1/4", the wood panel measures 10 1/2"x 4 1/2". It is very detailed depicting  a Medieval Knight / Crusader on a Horse among Trees. I don't believe the metal is copper -maybe brass. Very good condition no chips or cracks, some wear on the wood. There is a lot of patina built up on it. Please view photos for more detail. I'll be happy to answer any questions if I can.