Ever heard of complementary color afterimage? If you stare at a single color for a long period of time, then look at a white surface, an afterimage of the complementary color will appear. Try it for yourself.

This is why surgeons usually wear green or blue scrubs. Because they keep staring at blood during a long operation, when they shift their gaze to something white, distracting green/cyan afterimages appear. Wearing the same color lessens this effect. Just a little something I learned from Detective Conan episode 561.

What’s the afterimage color when you stare at gold?