Mackintosh style Rose copper foiled panel. Inspired by Charles Rennie Mackintosh, this art nouveau style deep purple rose panel is about 10.75 inches wide, and 7.5 inches wide. It is made with the copper foil technique – a process perfected by Tiffany for making window panels. Each piece is cut from sheets of glass, wrapped in copper foil; the foil burnished to the glass, reassembled and soldered. The piece is then cleaned, neutralized and polished to a shine.