Introduced on The Adventures of Superman radio show in 1943, the radioactive fragments of Superman's home planet have been keeping him humble ever since. What began as a single variety of Kryptonite eventually became a rainbow of varied colors and effects...all of which I'll be highlighting at different points during Superman@70 month. Think of it as an extended "Kryptonite Geology Lesson".
In this first installment, I'll be covering the most high profile, or "primary" varieties of Kryptonite, all of which occur naturally (i.e. the explosion of Krypton), or were altered through strictly natural phenomena. Later installments will cover man-made alterations and the more obscure varieties of Kryptonite.
Note: Since there are plenty of varieties from the comics to cover, I won't be including any of the divergent types of Kryptonite featured in movies or TV shows (such as Smallville and its bizarre variations). Also, I'm aware the histories and effects of various Kryptonites have been altered since Superman's 1986 reboot, so rather than get into all of that, I'll be focusing on the classic (pre-1986) versions. Of course, new varieties of Kryptonite that came along post-1986 will be featured.
First Appearance (comics): Superman #62 (1949)
History: Highly radioactive fragments of the planet Krypton.
Effects: Causes weakness and eventually death for all superpowered Kryptonians within range of its radiation. Green Kryptonite has no effect upon non-superpowered Kryptonians or humans.
History: Originally a substance "100 times more powerful" than Green Kryptonite (in Adventure Comics #252), three issues later in Adventure Comics #255, its creation is the result of Green Kryptonite passing through a mysterious red "space cloud".
Effects: Triggers bizarre behavior or radical transformations in Kryptonians. The effects are non-lethal and last for 48 hours. Each piece of Red-K causes a unique effect that cannot affect the same Kryptonian the same way twice.
History: Created when Green Kryptonite drifted through (yet another) mysterious space cloud.
Effects: Deadly to all plant life of any world (along with certain microbes).
History: Created when Red Kryptonite was exposed to high amounts of atomic radiation (as revealed in Superman #177).
Effects: Permanently removes superpowers from Kryptonians by destroying the ability of their cells to process yellow sun energy.
History: Thrown free from the explosion of Krypton, Argo City and its people survived their planet's destruction. However, the foundation rock that Argo City rested upon changed into "Kryptonite", eventually wiping out its entire population (with the exception of Supergirl and her parents). Realizing that non-powered Kryptonians were supposed to be immune to Kryptonite, DC later explained that the people of Argo City actually succumbed to "Anti-Kryptonite".
Effects: Causes weakness and eventually death for all non-powered Kryptonians within range of its radiation. Anti-Kryptonite has no effect upon humans or super-powered Kryptonians.
Of course, the most primary of the primary colors is the one that never actually appeared in a Superman comic book. Pre-dating the Kryptonite of the radio show, a "lost story" by Siegel and Shuster discovered in 1989 featured K-Metal, a Kryptonian mineral that weakened Superman! In addition to this development, the story also included Clark Kent revealing his Superman identity to Lois Lane...so perhaps these big events pushed the envelope too far for DC and their already ambitious marketing plans for the Man of Steel.
History: Clark Kent suddenly became weak when in the presence of a meteor fragment found by Professor Winton. Winton explained it was a fragment of a destroyed planet named "Krypton", which Clark then realized was the world of his birth.
Effects: In addition to having the same weakening effects as Green Kryptonite, K-Metal could also grant temporary super-strength to Earth humans.
Stay tuned for Altered States, part two of the The Kryptonite Chronicles!