When you first hear about Seastone, you may think it’s just some piece of pebble you find under the ocean. However, this Seastone we’re talking about is provided with rare minerals, having the ability to counter devil fruit users ability. As you may know, devil fruit users are weak against the ocean and it’s there during numerous occasions in the show when Luffy is drowning. Even in episode 1, Luffy is inside a barrel, this is because he’s aware he lacks the ability to swim.
How Are Seastones Used?
![One Piece Big mom detained and handcuffed with the Seastones](https://www.gamescooper.com/wp-content/uploads/2023/10/Big_Mom_caged_in_seastone_chains1-1024x576.jpg)
Seastones come in varieties of forms, but their sole purpose is to be able to fight against devil fruit users or to detain them. Seastone handcuffs are really common and one of the greatest things about these handcuffs is that they are essentially unreakable. Even during the rescue of Trafalgar Law, during the Dressrosa arc, even though Luffy can use Haki (the One Piece power system), he had to use the key supplied from Viola. Seastone in general is really effective against Logia users, because without Haki, the user cannot be face real danger. Handcuffs are only in use for a short duration. If you want to properly confine devil fruit criminals, a cage made out of Seastones can work. For example, in Impel Down, the cages seastone.
Another use of applying seastones is using them on weapons. If you’re taking on devil fruit users, the shape of handcuffs are kind of inconvenient. So researchers have applied this material onto a weapon. The government has a lot of power against seastones, as Dr Vegapunk worked on it a lot. Hence why a lot of the marine force equip themselves with seastone gears. Smoker, a marine vice admiral, is permitted to be equipped with a seastone weapon known as Nanashaku Jitte.
Smoker is first introduced when Luffy and his crew visit Rogue Town. Before heading to the mountain to get out of East Blue. Luffy encounters Smoker during this part of the story and pre-timeskip Luffy didn’t have the ability to touch Logia users. Therefore, he struggled fighting against Smoker, until a mysterious man (Monkey D Dragon) appeared behind Smoker to stop him.
Seastone’s Area Of Impact
![One Piece Luffy is restrained with Seastone](https://www.gamescooper.com/wp-content/uploads/2023/10/Luffy_cought_with_Seastone1-1024x576.jpg)
If you were somehow restrained by Seastone, how could you get away? Seastones only affect you, if you are physically in contact with it. A good example is when Mr 3 uses his devil fruit powers (which is the ability to freely manipulate wax). Thus freeing the inmates from Impel Down by creating a key-shaped wax and freeing them from the seastone cuffs. This is also on full display when Luffy tries to free Ace during the Marineford arc.
Another example of freeing someone who faces this treatment from Seastone cage or handcuff is when Trafalgar Law uses his devil fruit ability. This consequently enables him to switch position between two objects. As long as Law isn’t touching the Seastone, he is able to free anyone. The opposite to this example is when Law takes on Basil Hawkins. He shoots Seastone nails into Law’s body, disabling him from the use of his ability.
Fighting For The Key
![](https://www.gamescooper.com/wp-content/uploads/2023/10/Robin_Handcuffed_in_Seastone1-1024x577.jpg)
There is one specific arc which involves seastones that could be classified as one of the best arcs and this is the Enies Lobby arc. During this arc, Nico Robin is in custody willingly in order to spare Luffy and his crew’s lives, however none of them wanted this protection, especially if it meant sacrificing Robin.
Robin was captured with a seastone handcuff, as she is a devil fruit user herself (because she ate the flower-flower fruit). This arc involved taking out CP9 agents (world government finest agents at the time) and stealing the key for the seastone handcuffs. Defeating everyone apart from Rob Lucci, all the key was gathered and Robin was finally free.
When the fight between Luffy and Rob Lucci had concluded, Luffy’s body momentarily became paralyzed, and their last crew, Merry came to help. This enabled the whole crew to evacuate to Water Seven and soon after, they burnt down the ship, as Merry was no longer capable of setting sail.
Seastone’s Hidden Technology
![](https://www.gamescooper.com/wp-content/uploads/2023/10/Seastone_used_under_Marines_ships1-1024x576.jpg)
Did you ever think to yourself, why Marine ships are never subject to the wrath of Sea King creatures? There is a hidden secret behind this and it’s a cool feature on the ship itself. Dr.Vegapunk Discovered that Seastones have the ability to hide their presence away from the Sea King creatures. There is a layer of Seastone on the ships and this is what allows them to travel through Calm Belt with ease.
As mentioned before, Seastones are indestructible because of their key ingredient. During the Dressrosa arc, Frankie struggles to destroy the SMILE factory due to it’s structure with Seastones. Including Seastones into a building will make them indestructible, and this is seen when Doflamingo unleashes his “Bird’s Cage. ” But the factory just bends inwards without the strings piercing through the building.
How Useful Are Seastones?
![One Piece Big Mom fully covered in Seastones](https://www.gamescooper.com/wp-content/uploads/2023/10/Seastones_are_used_to_capture_Evil1-1024x576.jpg)
So after all this, are seastones worth using? Hopefully your answer is a “yes”, because Logia-types no longer feel special. Before Haki is properly introduced to the series, all the Logia-type users thought they were invincible and untouchable. However, this mineral drags them back to the same playing field as a non-devil fruit user. Seastones not only disables the use of their devil fruit ability, but they can temporarily weaken the actual person. Whenever Luffy is handcuffed by a seastone set, you can see his facial expression changing. It inflicts quite the blow.