|Item Category||Magic Tool, Jewel|
|Recipe|| Rainbow Fragment x1|
|Skills||Defense UP, Defense UP+, Ailment Reducer, Ailment Reducer +|
|Base Cost||307 cole|
- "A ring with a really big red jewel. It has the power to summon a powerful guardian to protect the user from an enemy's attacks."
- — Atelier Meruru description
The Guardian Jewel is a synthesized item in Atelier Meruru: The Apprentice of Arland.
When used in battle, it will increase the defense of the party and will also help to reduce the risk of status ailments for the duration of the battle. They are required to make the Promise Band accessory.