Silver Kryptonite has the ability to make Superman act Crazy and paranoid.
Silver kryptonite: made an appearance in the fifth season episode entitled "Splinter". Like the previous comics incarnation, this silver form was not a true form of the stone. In the episode, Clark pricked his finger on a rock that was black and had silver-metallic clusters, and subsequently became increasingly paranoid, hallucinating that others were conspiring against him. In the episode's final scenes, it was revealed that a splinter of the element entered Clark's bloodstream. It was also shown that silver kryptonite was created artificially from the liquid metal which forms Brainiac's body.
