In my realm, all of those who are in direct lineage of nobles possess a gene which gives them a psychic power. During battles, these nobles wear an armor made of a metal which on one side, repells psychic attack, and on the other side, amplifies it. I'm just wondering, how technical do I have to get on which two metals I choose? My original idea sprouted from one in which all nobles originated in a high concentration of ley lines, but that was when the genre was sci-fi instead of fantasy and the story took place in present day. Now it takes place in a fantasy-ish land. But it IS NOT magic. It just is what it is. Thoughts?