By enlarging the pupil in the eye a bit. Green is the color of Naga and the snakes and it fits better with silver and metal than red.
It would be nice if you upload in your post at this Icon thread, few same icons with different coloration, such as golden ring, not silver, and the one with green eye.
Oh, and can I see the wip, please? Not accusing you of anything, just want to see how you did certain things.
If i show you my psd file you will say "What a mess !?!" (Because of to much layers)
But i manage to find some of the wips i saved
1st: Made the basic shape of the ring
2nd: Basic shading and highlights
3rd: Found that my shadings are wrong so i started making new shadings
4th: Done with the new shading
5th: Started the ring shading
6th: Added the eye from my BTNEyeMedalion
7th: Fixed the shadows on the eye and again found error in my ring shadows so i fixed it + rendering on the ring + made a copy of the ring and went "Filter>Blur>Gaussian Blur" so i don't have bad edges (Placed the blured layer behind the ring)