Mercedes has a really nice silver i think called Sterling Silver or something. I have the number at the shop and will post it tomorrow. Its a nice clean color thats not to coarse. Something you might want to try is take a drive through a few new car dealerships and look for something that you have in mind where you can view it on a large scale. The reason i say new car is it narrows down identifying the color to 2012 after that all you really need is the make and model. You can generally find the color number with a book quick search at the paint supply place.
you can also go to this site
on the right side there is a "find you OEM color" tab you can usually find the factory codes here to. The color samples are meaningless but you can narow it down sometimes. helps if you can get a color name off a window sticker to.