yes. you would set it up as a spot color - similar to how it's done for printing white ink. I'm not sure if that machine can do silver or not - but I will warn you... once you dedicate that slot to silver - there is no going back. At least that is what I understand regarding our Roland XR-640. We have never dedicated it.
Instead we have an Epson Surecolor and it does metallic silver or white. We do a bit of white (just did some today) - but I can count on one hand how many jobs I've done with silver.