White Oak Ash Daggers

The White Oak Ash Daggers are weapons which were forged by witches as a means of subduing the Original Vampires. By appearance, they resemble a simple thin silver dagger with an intricately designed hilt. If dipped in the ashes of the White Oak Tree, dating from the genesis of the vampire race, and placed in the heart of an Original Vampire, they almost instantly desiccate, neutralizing them where they remain "dead" for as long as the dagger remains in the Original's heart.
The daggers must be used only by humans, because if it is wielded by non-Original vampires and possibly Werewolves, the dagger will claim both lives. The daggers were originally owned by the first members of the Brotherhood of the Five, supernaturally enhanced vampire hunters.
The Original Vampire Kol Mikaelson wanted to make a dagger work on Klaus as payback for all the times Klaus daggered him. His knowledge of magic showed that he knew how to transform one of the silver daggers into a gold dagger, a dagger that could neutralize Klaus as a magic loophole to his werewolf gene, as he could not replicate the original spell that made the daggers. As Kol was possessing the witch Kaleb, Kol and Davina successfully created a gold White Oak Ash Dagger from a silver White Oak Ash Dagger by using Kemiya.