In the core series games
If held by a Camerupt, allows it to Mega Evolve into Mega Camerupt if its Trainer has a Key Stone. Each Trainer can only Mega Evolve one Pokémon per battle.
Unaffected by item negating effects (such as Embargo and Klutz). Item manipulating effects (such as Trick and Fling) cannot give Camerupt a Cameruptite or remove a Cameruptite from Camerupt.
Outside of battle
If held by a Camerupt, allows it to Mega Evolve into Mega Camerupt when it performs a Spectacular Talent during a Pokémon Contest Spectacular while its Trainer has a Key Stone. Camerupt will remain a Mega Camerupt until the Talent Round ends.
Pokémon holding Cameruptite in Pokémon Omega Ruby and Alpha Sapphire cannot be traded to Pokémon X and Y.
| One of a variety of mysterious Mega Stones. Have Camerupt hold it, and this stone will enable it to Mega Evolve during battle.
In the manga
In the Pokémon Adventures manga
In Omega Alpha Adventure 11, Maxie was revealed to have obtained a Cameruptite. After his apparent death, Blaise took possession of the Mega Stone.
In other languages
|| 噴火駝進化石 Pēnhuǒtuó Jìnhuà Shí
|| 噴火駝進化石 / 喷火驼进化石 Panfótòh Jeunfa Sehk
|| 폭타나이트 Poktanite