Mrrzy wrote: I tarnish silver, and my skin turns green if I wear copper...

That generally means that your skin is producing more sulfur than most. (If you eat a lot of onions or other things with certain odorants, most of which are sulfur-based, that might be why. It might not, too. :-)

The usual solution to that is to use titanium-based metals rather than copper or silver (that's the usual metal used in jewelry for this sort of things).

There are titanium guitar strings. I have no idea what they sound like. But it might be worth a try.