thank you everyone. the conclusion is that diamond are the best for me. like vAddicatedGamer said, the main advantage of diamond reinf. is that is can be crafted with quite easy-to-find elements. I was sticking it in all of my previous armors :) unfortunately I can't give you all the solution mark. it goes to hanns.g for posting first with accurate answer :)
But we are all winners!!!!
Cheers, mates. Happy gaming.