Attached Link: http://www.maxon-computer.com/deepshade/shader/shaders/mineral/011/011.html

Some of the best-looking metals I've seen are on the c4d deepshade site but I think they can be adapted for use in Carrara. I've attached a link to one of the gold&chrome shaders. You could use the c4d demo to see how they're put together (or just use the texture maps that come along with the shader). Real World Metals (available in this marketplace) also has some nice metal shaders for Carrara.