Emerald Brooch

The Emerald Brooch is one of the four keys needed to open Reborn's core. It is called "the seal of faith".
== In the game ==
The Emerald key was originally in the possession of Solaris' family. To spark his faith, Solaris lends El the Emerald Key for one night so that he may believe in Arceus. The next morning, the Emerald key has restored El's sight, cementing his religious beliefs. One day, the keys are stolen by Radomus, who asks a friend to turn them into jewellery. As thanks, Radomus gifts this friend the Emerald brooch. 
This friend was actually Sirius who also gives the Emerald Brooch back to Elias, who then gifts it to his daughter Luna. When Luna flees from Elias, she takes the Emerald brooch with her. During the events in the Subseven Sanctum, Elias rips the Emerald brooch off Luna and escapes. 
== Trivia ==
*The Emerald brooch is the only key that has demonstrated healing properties.