Sometimes, a collector/seller will attempt to restore a warped casino plaque (a plastic laminate; BG-type) to its original flatness by applying heat and weight which, will flatten the plaque, though not always allowing the molten plastic to flow to its original position and leaving a wavy (concave/convex) surface... along with movement of pigments below the protective surface and even blister a metalic lamé in the process, which will rarely occur in the manufacturing process.

Also, sometimes, a lunette can shrink in size and leave a space between the plaque core and the lunette composition. This unsightly gap is sometimes filled in with a clear adhesive and even coated with a clear lacquer to appear even and original.

Though I do not have any examples to exhibit here, I did send Jay P. two plaques from a London casino showing the finished restored plaques as they were sent to me, previously.