I recently completed new branding and logotype for the client, using a two colour palette made up of deep blue, and a metallic silver for printed media, and a mid grey for all screen media.
The client phoned asking for a 'clear version' of the smallest possible size, best possible quality, to which I supplied a .swf file.
The reply to my email...
"Is it possible to use metallic silver for the font in this format?"
...to which I had to reply...
"I'm afraid not. The RGB colour space of a monitor can only ever simulate the sensation of colour.
Silver ink has fine metal particles in it that lend itself to reflectivity. You can only hope to simulate this on screen, which is why I've used an approximate grey."