There are some things that just don't mix - toothpaste and orange juice for example. However, mixing metals is like mixing sweet and salty! Done in the right proportions, it creates an elegant balance that is just right!
THE BEST OF BOTH WORLDS
Often times having all finishes be identical is a quick way to make a space feel builder-grade. An easy and low pressure way to experiment with mixing metals, particularly in bathrooms, is to include chrome as one of the players. This is because chrome is so similar to a mirror that it is a perfect neutral starting point. Along the same grain of caution, start by mixing just 2 metals. Once your comfortable, or with the guidance of a designer, you could incorporate a third finish. However, overall the best thing to keep in mind is to use each finish more than once so no one is an odd ball.