We recently did a job where the client requested 2 different finishes of silver. It is very simple but gives a very interesting effect. The job was done in 2 color silkscreen with matte varnish.

To give the silkscreen colors a bit of a pop, we added a special white mask underneath them, the result can be seen here.

The way to set this up is simple; the areas that need varnish will be given a distinctive pantone (PMS) color. Vector art is preferred.