Pink kryptonite was introduced once as a throwaway gag mocking all the different weird and random effects they used to come up with. It hasn't appeared on more than that single page, and I don't think it was even on more than one panel.
Fluorine is a halogen. Highly chemically reactive, but not especially radioactive.
From what I understand of the article, the writers of Superman Returns wanted to describe the chemical makeup of kryptonite. So they threw together a bunch of random elements. Then this guy was digging around and happened to find a rock that just happened to contain most of those elements.
It's not even the same recipe given in
Superman III :
As we hear various humming, clicking, and whirring noises:
ON THE BLANK COMPUTER DISPLAY SCREEN ... it begins to show a message:
KRYPTONITE ... AN INTENSE HEAT FUSION OF:
Below it quickly prints the composition, element by element:
PLUTONIUM . . . 15.08%
TANTALUM . . . 18.0 %
XENON . . . 27.71%
PROMETHIUM . . 24.02%
C.U. GUS -- watching gleefully.
GUS
Uh-huh! Uh-huh!
ON COMPUTER DISPLAY SCREEN -- the computer has added to the list:
DIALUM . . . 10.62%
MERCURY . . . 4.08%
Sound: the whirring and clicking stop.
GUS smiles broadly as he reaches to tear off the printout sheet. He's done it!
But suddenly:
Sound: the whirring and clicking begin again.
The printout sheet emerges a little further as an addition to the list appears
ON THE COMPUTER DISPLAY SCREEN:
UNKNOWN . . . 0.57%
Not the best movie, granted (though it was fun in its own way), but at least that recipe includes some radioactive elements (plutonium and promethium). A good percentage of the makeup, too. (Of course, that radiation is dangerous to humans, not just kryptonians. But still...)
It is funny that this rock happened to have the elemental composition mentioned in the most recent movie, and that it happened to show up now (less than a year after the release), but that's about it. I don't understand the fuss.
Paul
