Hi JustMeP!

Nan Smith's Dagger series fits your bill. Clark has encounters with a piece of mixed green and red kryptonite that cause some distress.

Nan's stories fill the "Classic" part of your request, too. Here you can find her series guide: http://www.lcficmbs.com/ubb/ubbthreads.php/topics/259480/Nan_Smith_Series_Guide

Be aware that there are authors out there who have written one great story, too. I guess that's a clue for the rest of us to get cracking!

Shallowford