I've been working on the gold bits on Sophie, using the "non-metallic metal" method. This technique is a freaking pain in the ass! And it looks terrible until almost the moment you finish it, at which point it "pops" (or it may not because I did it wrong).
Of course, "real painters" almost always use this technique, not metallic paints:
Even in this dramatic and bloody work The Third of May, Francisco Goya took the time to carefully render a metallic shine on the soldiers' rifles, using only normal paints. The result is strikingly convincing.