Green kryptonite
Smallville-Earth Item
General Information
Status: Existing
Origin: Krypton
Physical Description
Color: Green
Usage Information
Used by:
  • Various
Used for:
  • Various
Media Information
First Appearance: "Pilot"
To think that such a small rock could give someone so much power.
Tess Mercer in Metallo.

Green kryptonite is the most common form of kryptonite, a radioactive ground mineral that made up most of the planet Krypton's structure, including its core.[1] Clark told Kara that kryptonite was "radioactive pieces of our home world" that landed on Earth in October 1989 during a spectacular and destructive meteor shower which struck Smallville and concealed the arrival of the baby Kal-El/Clark.

Early HistoryEdit

The meteor shower that brought massive amounts of kryptonite.

Kryptonite was also found on Earth in Asia, long before Krypton's destruction, suggesting it might be a naturally occurring radioactive element from Krypton or that someone brought it to Earth.

The Kawatche had a legend about special green stones brought by a man named Naman, which had strange effects on the people. The description of the green stones and their mutagenic effect on the Kawatche matches the profile of kryptonite.

A meteor rock.

It is unclear how radioactive pieces of Krypton made it to Earth hundreds of years before the explosion of the planet, though the naturally occurring element theory could be correct.

Either way, much more of the mineral arrived with the 1989 and 2005 meteor shower in Smallville. Since then traces of the mineral can be found across the globe, but especially in Smallville where the meteor shower was centered.

Powers and AbilitiesEdit

Effects on Kryptonians
Green meteor-rocks are commonly found around Smallville.

Green kryptonite emits a radiation that is extremely toxic to super-powered Kryptonians. The radiation itself first causes symptoms such as nausea, dizziness, pain, and weakness that eventually grow more severe until loss of consciousness occurs.[2] It "boils" Kryptonians blood when exposed directly.[3]

Clark weakened by green kryptonite.

Exposure to green kryptonite breaks down a Kryptonian's invulnerability, allowing outside forces to damage the body. Prolonged exposure or large amounts of green kryptonite will ultimately lead to death.[4] It has been noted though that as Clark gets older the effects of kryptonite seem to affect him a little less.[5]

Kryptonite in relics.

This type of kryptonite seems to have healing and energizing properties for Bizarro. Many metahumans with power bestowed upon them from green kryptonite can use that power against Clark Kent and other Kryptonians. However, Clark has also shown to be immune to other metahumans' abilities.

Clark uses green kryptonite and electricity to reverse the incomplete transfer of his powers to Lana.

Green kryptonite can be used to disable the red and gemstone kryptonite effects.[6] Green kryptonite, when in contact with a strong electric current (such as lightning), sometimes has the ability to transfer Clark's powers to humans and vice versa.[7]

Effects on humans
Jodi ingesting a kryptonite-tainted drink.

The effects of kryptonite on humans are usually irreversible. Green kryptonite can be briefly handled and sometimes even ingested by humans after being manufactured without immediate danger. Humans don't experience the weakness and incapacitation suffered by Kryptonians. However, long-term exposure to the green meteor rocks of Smallville has been shown to have significant effects on humans. Also, different types of kryptonite have different effects.[8]

Green kryptonite affecting a human.

Many of Smallville's residents (or even visitors) suffer from meteor rock infection. It often causes mutations, personality changes, psychosis, or a variety of other adverse reactions. The majority of kryptonite-infected individuals display phenomenal metahuman powers, but most are also psychotic versions of their former selves, with personality traits or desires often enhanced to the point of obsession.

Meteor rock infection also has been shown to have adverse physical effects:

  • Earl Jenkins and Steven Hamilton developed a neurological disease from meteor rock exposure which included uncontrollable tremors and psychotic behavior. Both eventually died from these ailments. [9]
  • Moira Sulliva's meteor rock infection rendered her unresponsive and catatonic for several years. [10]
  • Lex Luthor was rendered bald due to his exposure to meteor rock, which presumably increased his white blood cell count.
  • Wade Mahaney became intangible after injecting kryptonite as a tattoo ink. The molecules of his body sped up so rapidly that he could pass through solid objects, but the stress caused his body to start breaking down. [11]
  • The clone generated from Emily Dinsmore grew rapidly due to green kryptonite. [12]
  • Buffy Sanders contracted a form of rabies that had been mutated into a vampiric disease from meteor rock exposure. [13]
Lana wearing her necklace.

It should be noted that although Lana Lang wore a meteor rock necklace for several years, she did not experience any health problems related to meteor rock infection.

Chloe Sullivan also had a kryptonite-filled heart for nearly 20 years and suffered no ill effects. Lex also wore a kryptonite ring and was exposed to kryptonite objects in his vault, but has also so far has been unaffected.

Characters have developed mild psychosis:
Chloe Sullivan

A few infected individuals seem to escape psychosis or have developed mild psychosis while temporarily or permanently metahuman. An example is Chloe Sullivan. Before her power of empathic healing was nullified, it had not seemed to significantly change her personality. This is in stark contrast to her exposure to kryptonite gas, which significantly changed her personality. (She went drunk with power when she acquired the power to coerce the truth from others).

Lana nearly three years after absorbing large amounts of kryptonite, clearly healthy.

The same goes for Lana Lang. Who, along with her Tri Psi sorority sisters, killed with no conscience when infected by a meteor-rock-mutated form of rabies. Also, after she temporarily absorbed Clark's powers, she became obsessed with using them for revenge against Lex. This is in stark to her absorbing massive amounts of kryptonite gas into her nano-skin, and remaining significantly unchanged in her personality.


Green kryptonite in a lead box

The effects of the kryptonite on Kryptonians can be shielded or blocked with lead.[14] Also, some Kryptonian technology, such as Kal-El's ship, can neutralize the effects of kryptonite. LuthorCorp was able to develop a technology to absorb the radiation of the kryptonite.

Heat vision destroying Kryptonite.

Normally, heating green kryptonite results in the creation of black kryptonite. However, kryptonians are shown to be able to destroy green kryptonite with heat vision without changing it into its black variant.


  1. As witnessed in the season seven episode Kara.
  2. Clark frequently exhibits these symptoms when exposed. Dizziness and blurred vision were displayed in Phoenix, and he has passed out from it in Commencement and Progeny.
  3. As witnessed in the season three episode Phoenix.
  4. Chloe states that Clark will die if left in kryptonite-lined tunnels in Traveler.
  5. In Abandoned, Clark was in direct contact with kryptonite but it should be noted that at first he seemed little affected by it. It seems that Clark can use his other powers while being imprisoned in a kryptonite cage (Abandoned) .
  6. This can be witnessed clearly in Crimson.
  7. Leech, Asylum, Wrath
  8. For example blue kryptonite makes humans healthy and purify water, green kryptonite gives humans superpowers. When someone ingests enough kryptonite they emit the radiation so if someone ingested red k they would emit that radiation and effect Kryptonians.
  9. (Jitters, Duplicity, Chloe Chronicles).
  10. As witnessed in Progeny.
  11. (As witnessed in Kinetic.
  12. As witnessed in Accelerate and Forsaken.
  13. As witnessed in the season five episode Thirst.
  14. Clark learns this in Metamorphosis and keeps a lead box with a piece of kryptonite in it for emergencies. This formula also works with blue kryptonite