How do I restore the bronze paint on a ring made of cheap metal?

I got a pinky ring for really cheap a month or so ago. After wearing it for a few days, the bronze shiny finish began slowly fading off in some places, leaving a dull dark brown. Now the band of the ring is almost entirely dull brown, and the decorative part of the ring is shiny bronze, but with some brown areas.

Even though it was obviously made out of cheap metal (at one point it left a green-tinted band around my pinky), I really want to restore it because it has sentimental value. Is there any way I can fix it?

Jewelry cleaner? Jewelry paint?

As a side-note, I'm thinking perhaps it faded because when I wore it, the weather was extremely hot, humid and sweaty.