Memory Crystal

The Memory Crystal was a valuable device from the Mines of Marlion.

Iris Wildthyme used it to store her memories inside, which took a "ritual of fast[ing], pray[ing], and all kinds of rites" to perform.

After she had accomplished this, The Head tried to take it from Iris, and it almost succeeding, but Panda managed to reclaim it and destroy it, giving Iris her memories back. (AUDIO: Wildthyme at Large)