Petrification is the catalyst of the events of Dr. Stone. The term refers to both the event in which all humans and swallows in the Pre-Petrification World were turned to stone, as well as the process itself.
Understanding the source and cause for the Petrification is a key conflict in Dr. Stone, particularly in the Age of Exploration Arc.
On the day of the Petrification, some time in June in the year 2019, all humans around the world were mysteriously turned into stone statues. Earlier that morning, certain birds were also turned to stone, many confusing them for lifelike statues. The Petrification appears to have spread across the planet extremely quickly; according to Senku and Byakuya, the cause of the phenomenon likely originated in South America. Notably, the Petrification did not affect those not currently on the Earth's surface, the people aboard the International Space Station, for example, were spared from the Petrification.
Petrification takes the form of a blinding wave of light. As the light envelops the body, it quickly turns to stone. The light passes through solid objects, and those not inside the light wave are not petrified.
The cause of the Petrification is currently unknown. One of Senku’s goals is to determine the origin of the Petrification.
The Petrification Kingdom suffered an event where Matsukaze stated several of the Petrification Weapon fell from the sky. Several of the weapons were destroyed but one of them passed down to a new generation, specifically the hands of Kirisame. The exact radius of this Petrification can be somewhat controlled, and is used to prevent inhabitants of Treasure Island from leaving.
- Creatures affected by the Petrification are physically turned to stone. This stone is as brittle as regular stone.
- However, their minds continue to persist. Some compared the experience to sleep paralysis.
- Most creatures quickly lose consciousness, but it is possible to stay conscious with enough mental fortitude (as seen with Senku Ishigami and Taiju Oki).
- It doesn't work against animals aside from humans and swallows, as the Petrification started.
- Only their flesh turns to stone. A person's clothes and other inorganic items are unaffected and wear away as time passes.
As a result of the Petrification, the Earth also changed significantly:
- Vehicles in motion lost control and crashed.
- Flora and fauna were allowed to grow unimpeded.
- Without proper maintenance, buildings and other human structures eroded and collapsed.
- Natural disasters, such as flooding and volcanic eruptions, occurred without human interference.
- Maps memorized in the past are now useless for several reasons:
- Natural disasters changed the landscapes.
- The tilt of the Earth's axis has shifted, meaning that Polaris no longer points true north.
Those afflicted by the Petrification can be depetrified ("revived") in two known methods: a combination of maintaining consciousness while being petrified and being in contact with nitric acid or being given the Stone Formula. Senku and Taiju are the only known people to revive completely via the former method.
The speed of the depetrification via the Stone Formula depends on the weathering of the statue. Newly petrified statues will depetrify significantly faster than those that are have been petrified for longer time periods.
If a person's stone statue is broken, it cannot be depetrified. (Attempting to do so results in a corpse.) However, if a broken stone statue is reassembled perfectly, the Stone Formula will work. Though in Senku's experiments, the entire body was broken and he couldn't put it back together. So it remains unknown if petrification can be used to "handicap" an enemy by breaking off a limb and then unpetrifying them so they can still live, but no longer have the ability to pose a threat.
Being revived from Petrification heals any injuries the person may have had previously, including broken bones and brain death; this also includes gradually disabling things like arthritis. Cracks that may have formed in the statue via weathering will also heal, leaving black scars in their place. Senku explained that the scars are due to the cracks in their bodies being sealed up upon revival. (Being repetrified and then depetrified before weathering heals these scars.)
Pre-Petrification World humans that have been depetrified include:
- Senku Ishigami (via maintaining consciousness and the Cave of Miracles)
- Taiju Oki (via maintaining consciousness and the Cave of Miracles)
- Tsukasa Shishio (by Taiju)
- Yuzuriha Ogawa (by Taiju)
- Gen Asagiri (by Tsukasa)
- Yo (by Tsukasa)
- Nikki (by Tsukasa)
- Minami Hokutozai (by Tsukasa)
- Hyoga (by Tsukasa)
- Homura (by Tsukasa)
- Ukyo (by Tsukasa)
- Mirai Shishio (by Senku)
- Ryusui Nanami (by Senku)
- Francois (by Senku)
Stone World humans that have been depetrified include:
- Chrome (by Senku)
- Kirisame (by Senku)
- Matsukaze (by Senku)
- Senku seeks the petrification device to use as a stand-in for proper modern medical procedures. (No doctor has been de-petrified).
- Kaseki notes he felt a lot better and demonstrated great agility for his age upon revival indicating that the process of de-petrification restored some of the youthful vigor he used to have.
- It is shown that no matter how long a person is petrified, they will not age and remain the same until after depetrifying.
- Bad eyesight cannot be fixed by de-petrification, as Kinro still wears his glasses and Suika still wears her melon mask after their respective revivals.
- It's currently unknown if a stab wound (which Ginro suffered five of) will become black marks upon depetrification or simply be sealed up normally.
- Even if blood has left the body, it can still be petrified if still fresh.
- The blood coming from Ginro's wounds turned to stone rather than remaining a stain on his outfit.
- A cosmetic side effect seems to be that dyed hair can no longer return to normal. Possibly due to the fact it was "frozen" in place; however, no explanation has been given as of yet.
- Gen is such an example. As despite a year passing after depetrification, he still had half white hair without access to dye.