kryptonite discovered

I don't know about anyone else, but I've heard from a few people now about the recent discovery of kryptonite, specifically the chemical sodium lithium boron silicate hydroxide," which is how it was identified in the 2006 movie "Superman Returns." Disappointly, it is not a green mineral, and it emits no measurable radiation.

 

That is, it emits no radiation that is harmful to humans. Lone survivors of the doomed planet Krypton may be another story, however.

 

But please recall that in addition to green kryptonite, which weakens Superman and effectively gives him radiation poisoning; pre-Crisis there was also blue kryptonite, which would produce random side effects on him, such as causing him to grow to gigantic heights or to grow extra arms; and gold kryptonite, which would take away his powers completely. If you've ever read Alan Moore's "Whatever Happened to the Man of Tomorrow?" you'll remember that Superman on Earth-2 (a pre-Crisis Superman) exposed himself to gold kryptonite after a tremendous struggle with oldtime supervillains at his Fortress of Solitude, and became an ordinary human under the name Jordan Elliot.

So perhaps this is a hitherto undiscovered "white kryptonite," whose properties have not been discovered, because the radiation it emits is on wavelengths beyond our ability to measure.