Wolverine's Adamantium

I was looking through some of my collection when I found a copy of "Guardians of the Galaxy" (don't ask me why I bought it). In one of the issues, Wolverine's daughter (or other future relative) is in search of Wolverine's skeleton. All she had was a piece of one of his claws. Can anyone tell me how someone managed to break Wolverine's adamantium claws? I thought adamantium was unbreakable.

Thanks in advance.

LIGHTSABRE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!DUH LOL 😆

in Wolverine: The End his claws are cracked and broken too. i guess after dozens years of use, they got too worn out. i mean, look what he does with them, he certainly doesnt try preserving them.