The rule about never mixing metals is gone, and honestly it was never much of a rule. What makes a stack look intentional is repetition, not matching: the same finish repeated twice, or one metal clearly leading. Below, the necklaces, earrings and bracelets I would combine right now, from Prada's Eternal Gold through Ann Demeulemeester's heavy silver chains. Pick a lead metal, then let the second one interrupt it once.

Start with the longest piece and build up. Prada's Eternal Gold pendant is the quiet anchor, Ann Demeulemeester's macro chain is the one that does the talking.

Earrings are where mixing is easiest, because the two metals never sit side by side. Oscar de la Renta's pineapple pave and Joseph's bean hoops are both worth it.

Wrist stacking works best with three pieces at most. A wide cuff, a chain, and something small. Victoria Beckham's chunky cuff is the piece I wear most often.

If a stack feels wrong, take one thing off rather than adding a fourth. It is almost always too many pieces rather than the wrong metal.