The Adamant Orb is a sphere made of diamond, an exclusive item for Dialga. It boosts its Dragon and Steel type moves, but only for Dialga. It can be sold for 5000P. In Platinum it can summon the legendary Dialga.
If an Active Pokémon has Weakness to steel type, Dialga's attacks do 20 more damage to that Pokémon (before applying Weakness and Resistance).
- Diamond: It can be found behind the location where the player fought Dialga, at the back of the Spear Pillar ruins.
- Platinum: It, along with the Lustrous Orb, can be found in a small back cave in Mt. Coronet only accessible via waterfalls.
- Black and White: It can be obtained from the Shadow Triad on Marvelous Bridge after the stories completion.
- Black 2 and White 2: It can be found along with the Lustrous Orb and the Griseous Orb in Dragonspiral Tower, right before the player can catch Zekrom.
- HeartGold and SoulSilver: It can be found at the Sinjoh Ruins.
- Omega Ruby and Alpha Sapphire: It can be obtained in Hoenn Route 128.