Since purple is a cool color, metals such as silver or white gold would complement your veins nicely. The cool tones of these metals would enhance the purple hue of your veins.
I meant a dark, royal purple
In that case, a metal like yellow gold or rose gold would contrast beautifully with a dark, royal purple. The warm tones of these metals would provide a striking contrast to the deep purple color, creating a luxurious and regal look.
Well, which one? Yellow gold, or rose gold?
For a dark, royal purple color, rose gold would be a stunning choice. Rose gold has warm undertones that would complement and enhance the richness of the purple, creating a sophisticated and elegant look. Yellow gold may also work well, but rose gold would provide a more luxurious and modern touch.