The Mima Jewel (魅魔の宝玉 Mima no hougyoku, Demoniac charm jewel) is a major plot-related artifact from the game Summon Night.
The Mima Jewel was created in ancient times by the high summoners of Lyndbaum, having the sole purpose of guiding outcast summons and fiends from Sapureth back to their homeworld in order to prevent sudden attacks and possible casualties without harming them in the process. The Mima Jewel grants it's user the power to control at will the conciousness of Sapureth's stray summons. Unlike Summonite stones, this jewel does not require making a pact with summon creatures, thus turning them into mere puppets.
In Chapter 12, Gibson and Mimoza, high summoners from the Blue Faction, were sent to Saijent with the task of recovering the Mima Jewel, after being stolen by a band of black-robed men. After a fight with Vanossa, he reveals he was behind the robbery and plans to use the jewel to become more powerful.