x men cinematic universe - How could this Adamantium piece be destroyed in The Wolverine?

In The Wolverine there is a scene in which

Wolverine's Adamantium claws get sliced off by the Silver Samurai.

I know about the Silver Samurai's ability of generating a tachyon field surrounding (usually) his sword, but I thought this couldn't cut through Adamantium.

So, how could this happen?

Answer

This is a failure of canon and writing regarding the issue of indestructible metals. Marvel has made little effort to describe Adamantium in any given detail and it defies the rules that most metals use regarding taking damage or being destroyed.

TLDR

Given the premise that the Silver Samurai was supposedly capable of generating a tachyon field (read that as a rare high-energy field) surrounding an already super-sharp blade forged of True Adamantium and wielded with superhuman strength and precision, this might be capable of being part of the TVtrope "Crowning Moment of Awesome" allowing the claw to be broken.

• I also note that the Marvel characters when they come to the big screen are also not quite as powerful, irresistible or capable as they are seen in the comics. Is this an attempt at realism or simply a production consideration when the character is converted is a matter of debate.

Building the Case

Adamantium comes in a variety of flavors and capacities for absorbing or resisting damage. The original premise of Adamantium was that once it was set, it could not be broken by anything less than a force of cosmic origin (beings such as Galactus, the Silver Surfer, Odin, Zeus or other such senior deities) or that of an Omega level mutant (including Franklin Richards, Jean Grey as the Phoenix or Magneto).

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  Primary Adamantium: Made only once mixing Adamantium and Vibranium together. Never duplicated, and considered one of the most indestructible materials in the Marvel Universe. Only found in Captain America's (Earth-616) shield.

  
  


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  True Adamantium: When Primary Adamantium couldn't be made, they created the next best thing, called True Adamantium. Nearly indestructible only beings of incredible capacity, capable of manipulating cosmic forces, altering reality, or using the very rare molecular re-arranger technology. Found in places like Ultron's nigh-indestructible body.

  
  


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  Adamantium Beta: After Wolverine was exposed to Adamantium during the bonding process, his regenerative powers altered the nature of the Adamantium allowing it to be regenerated like his normal skeleton. (Don't ask because this makes no sense to me either.) This Beta Adamantium is supposedly as strong as True Adamantium but that is unlikely since his bone structure would be as porous as his bones were originally.

  
  

This would make his bones almost completely unbreakable except by forces capable of doing incredible damage dealing or by being able to bring an incredible amount of force on a tiny segment of his bone structure.

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  Wolverine's Adamantium-laced bones and claws (which were also bones) are made of "Adamantium Beta" which is supposedly as indestructible as True Adamantium but can be affected by incredibly powerful force weapons (like Cyclops' optic blast), Vibranium (the anti-metal variety) weaponry and other Adamantium weapons.

  
  


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  The limitation of Adamantium Beta is that it is still more vulnerable to destruction than the hardest versions of Adamantium and therefore it is theoretically possible for it to be damaged or broken.

  
  
  

Apocrypha

Marvel has never truly explained how the bonding process allows Wolverine to repair his broken bones that are laced with Adamantium. The wiki at Comicvine also lists this information without a reference.

Adamantium Beta: The only known occurrence of Adamantium Beta was during the Weapon X Project. By the second part of the procedure when they laced his bones with Adamantium there was a reaction with his healing factor that bonded metal and bone. As a result the Adamantium "heals" just as his bones do.