Tulle is a fine net (mesh) material of nylon, silk or metalic thread that
is added to the color surface prior to the protective film being applied.
In more recent production, a tulle-like design litho film is used in place
of the actual mesh.
The Monaco piece has a gold metalic tulle.
The Grand Casino FORGES-les-EAUX has tulle only applied to the lunette.
The Sahara plaque has an image added in the lunette and a very fine tulle
added to the plaque's surface.
The Casinos In Austria plaque has a litho-film design tulle added, but it
does not continue into the lunette.