It’s Week 2 of my teaching stint in the Johns Hopkins University Center for Talented Youth summer program. So, while a dozen gifted 11 and 12-year olds continue to learn all about creative writing, here’s my official unofficial researcher John Wells, with more of everything you want to know about Kryptonite?

Last week, we discussed the development of kryptonite and the eventual creation of Red K.

Even as Red K was developing, Green K’s use was being expanded to develop actual super-villains. Perhaps inspired by Jimmy Olsen’s intake of kryptonite-tainted fruit (which led to his masquerade as the shimmering “Boy From Mars” in 1958’s JIMMY OLSEN #27), 1959’s ACTION #249 saw Luthor ingest a serum that transformed him into a glowing Kryptonite Man. The same month’s SUPERMAN #127 used the combined radiation of uranium and kryptonite to turn a chimpanzee into the colossal Titano, a super-ape with kryptonite-vision. He was loosely based on the earlier Chandu from 1955’s ADVENTURE COMICS #219 and, far more directly, on Big Boy from the newspaper strip.

And a few months later in ACTION #252, we meet John Corben, a murderer who is nearly killed in a car accident. A benevolent scientist builds Corben a metal body with a “heart” powered by uranium capsules that must be replaced on a daily basis. As Metallo, Corben is a criminal juggernaut but he becomes obsessed with finding an alternative to uranium. He finds it in kryptonite, whose power will, according to Doctor Vale, last “forever.” Unfortunately for Corben, the sample he snatches from the Metropolis exhibit hall turns out to be nothing more than a painted rock and, with that in his chest, Metallo quickly drops dead.

Only Titano would be developed further during the Silver Age (though Doctor Kryptonite, a villain similar to the transformed Luthor, appeared in 1967’s ACTION #349) but 1960 introduced another recurring menace — the Kryptonite Kid. A teenage criminal whose spacecraft passed through a Green K cloud, the emerald villain and his matching dog very nearly killed Superboy not once but twice, first in SUPERBOY #83 and again in #99 (1962). The first time, the Boy of Steel and Krypto are saved by Master Mxyzptlk. The second time, they lure the Kid and his dog through a red kryptonite space cloud that not only alters the color of their skin but exchanges their nasty dispositions for virtuous ones. Superboy noted in the last panel that, if Red K ran true to form, the Kid’s transformation would be short-lived.

Readers quickly wrote in pointing out that, as a non-Kryptonian, the Kid shouldn’t have been affected by the Red K in the first place, prompting an editorial explanation in SUPERBOY #101 that said, in essence, that the original Green K cloud had given him a metabolism akin to Kryptonians.

Thanks in part to the presence of this more scholarly breed of comics fans in the letter columns, further details were forthcoming as to the nature of kryptonite. The fact that kryptonite had been melted, crushed, liquefied, et al. almost since day one had pretty much confirmed that it wasn’t invulnerable on Earth like everything else Kryptonian. Why, then, didn’t they just burn up when they hit the atmosphere? According to SUPERMAN #130, it was because “kryptonite can’t combine chemically with oxygen, which causes combustion.”

1968’s ACTION #370 revealed that the infant Kal-El’s rocket had passed through a space-warp between Krypton and Earth. So, when a reader in #374’s letter column asked how so much kryptonite could have arrived on Earth from a planet that was “at least eight light years away,” assistant editor E. Nelson Bridwell had an answer prepared: “The K got here through the warp.” The explanation was tweaked in THE AMAZING WORLD OF SUPERMAN‘s origin retelling (1973), where it was established that the rocket was actually equipped with a “warp-drive” and THAT’S what created the short-cut in space.

Given the fact that several stories like 1958’s SUPERMAN #123 had established that kryptonite only affected super-powered Kryptonians, a reader eventually asked about Argo City, the home of Supergirl that had survived in space atop a lead-covered wedge of Green K. Since those Kryptonians had no enhanced powers, the lead shouldn’t have been necessary, right? Wrong, said the editorial response in 1964’s ACTION #317. This was ANTI-kryptonite, which affects normal Kryptonians. And anti-kryptonite was, of course, only the tip of the radioactive iceberg.

1960, in particular, had produced a bumper crop, starting with X-Kryptonite in ACTION #261. After making several attempts at chemically destroying a marble-sized piece of Green K, Supergirl finally tosses it into the woods. There it’s discovered by her pet Streaky, who is bathed it its radiation and becomes Super-Cat. The effect is only temporary but future stories made sure the fabulous feline came into contact with the mutated kryptonite again.

Later in the year, Superman creates Blue Kryptonite, using the same imperfect duplication ray that created the Bizarros. Though the Man of Steel only intended to use the stuff as a threat to ward off an invasion, Blue K proves just as lethal as its green counterpart, actually killing off the Bizarro-Supergirl (SUPERMAN #140). Brrrr.

Lastly, there was White Kryptonite, theoretically formed by another of those darned cosmic clouds in space (ADVENTURE #279). It was only toxic to plant-life, Kryptonian or otherwise, which isn’t actually as limiting a plot device as it sounds. White K would resurface again throughout the 1960s, 1970s and 1980s but never as effectively as in 1968’s spin on the Death of Superman (ACTION #s 362-366). An earlier story had established the existence of an incurable, fatal Kryptonian illness called Virus X and in this serial, the Man of Steel is actually infected with it. In his death throes, Superman is finally jettisoned into the sun of a distant planet while the celebratory Bizarros shower him with all varieties of kryptonite — including White K. Unexpectedly restored to full health, Superman realizes it’s because “Virus X… was a form of plant life, like bacteria.” Setting aside the fact that science would soon prove that bacteria WASN’T plant life, it was still a pretty clever solution for the time period.

Coming along in 1962 was Gold Kryptonite, which wasn’t deadly per se but DID permanently strip Kryptonians of their super-powers. Its first appearance was in an Imaginary Tale (ADVENTURE #299) but it became canon just three months later when the embittered Quex-Ul was exposed to the element (SUPERMAN #157). WORLD’S FINEST #159 (1966) added the ominous detail that the effect radius of Gold K is a mere two feet. The origins of this variation may have been tied to a mysterious green comet that predated Krypton’s explosion and which would also permanently erase super-powers (SUPERMAN #172). How does one tell Gold K from regular gold? “There are telltale signs for those in the know,” asserts the letter column in JIMMY OLSEN #96. “For instance, Gold K crackles and pops. Can ordinary 24-carat gold do that?”
Jewel Kryptonite was another specially-created variety, this one prepared by time-traveling Phantom Zone criminal Jax-Ur from Krypton’s Jewel Mountains. It amplified the Phantom Zoner’s “mental commands and [converted] them into energy beams which [detonated] any explosive material” they set their sights on (1964’s ACTION #310).

And then there were the one-off varieties. Stuff like ACTION #350‘s Kryptonite-Plus (“a super-powerful isotope that will finish off [Kryptonians] in minutes”), JIMMY OLSEN #92‘s artificially-created Magno-Kryptonite (“It [clings] with unbreakable force to anything that comes from Krypton”) and JIMMY OLSEN #70‘s Silver Kryptonite. No, wait. That last one was a hoax to commemorate Superman’s 25th anniversary in Metropolis. The chunk of Silver K was actually a stylized cabinet that opened to display silver busts of the Man of Steel’s closest friends.

There was even an unusual sub-series called “Tales of Kryptonite” (1964 & 1965’s SUPERMAN #s 173, 176, 177, 179), which followed a single piece through an increasingly preposterous turn of events, one that saw it altered from green to red to gold in the course of the saga.

The sheer abundance of kryptonite on Earth had reached the stage of absurdity by the mid-1960s, by which point even petty thieves seemed to have easy access to the meteor rocks. In 1964’s JIMMY OLSEN #81, for instance, Jimmy has the Superman Robots gather every chunk that the Man of Steel has ever hidden on the planet, something on the order of one thousand pounds. And then they gather more from space, coming up with, exaggerates Jimmy, “at least fifty tons!” When aliens expose Supes to this green stockpile, he shrugs it off! Says Jimmy, “I figured that just as a small amount of electricity can kill someone, but a colossal electrical charge can’t… a super-abundant amount of kryptonite might not kill Superman.” Superman’s pal, indeed.
As late as 1970’s WORLD’S FINEST #196, showers of the stuff were still hitting Earth. In this issue, citizens were asked to gather the green rocks and toss them aboard a cross-country “Kryptonite Express” for eventual disposal.

Next week: The conclusion of the history of Kryptonite. While you’re waiting, dont forget my daily Anything Goes Trivia at

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