An easy rule of thumb is that warm metallics like bronze, copper and gold compliment warm colors and cool metallics like silver and platinum compliment cool colors. You can also play warm metallics against cool colors and vice versa for contrast.
1. A bronze trunk plays off of warm colored accessories. Coco + Kelly.
2. Silver, gray and soft pink are a subtle but pretty combination. House Beautiful.
3. A silver tiled backsplash compliments a sky blue ceiling in this kitchen. CasaSugar.
4. A silver grass cloth wall covering plays beautifully off of purple bedding and a blue vase. House Beautiful.
5. Patterned gold wallpaper and a gold pouf look are paired with a saturated blue rug for a rich combination. HGTV.
(Images: as linked above)