Brightening a Dull Copper Platter

I recently acquired a hammered copper platter (grapes), that was made in England. The Platter has been painted, or treated, with a patina (spelling?) green substance. The appearance of the platter is quite dull and I have tried to polish it with a copper and brass substance, with no good results. Must I use a paint remover ⇦ on eBay or Amazon [affil link] or what would you suggest?

If it is a true patina, why take it off. People go to great lengths to get a good patina on copper. If it is paint, that is another matter.

If you would like to keep the patina and just brighten it up, try Dorlands Wax Medium [affil link]. You can get this at any art supply store. You can sit your platter out in the sun for a few minutes to heat it up, then use small flat brush to (paint) on the wax. It will melt right on. Then set the piece inside for a while to cool off. The next step takes a little elbow grease. Using a clean soft cloth, burnish in the wax (buff). It might take two coats. This will give the piece a nice warm glow.