Unstealable Jewel

Unstealable Jewel (called Intangible Treasure on the Revival disc and Xenogears Vinyl - SHINKAKU -, sometimes unofficially referred to as The Treasure Which Cannot Be Stolen) is Disc 1, Track 16 on the Xenogears Original Soundtrack, track 17 on the Xenogears Original Soundtrack Revival Disc -the first and the last-, and Track 4 of the A-Side of the first disc of Xenogears Vinyl - SHINKAKU -.

A vocal remix of the track, Memories Left Behind (Revival Version), was made for the Revival disc, and was also performed at the Xenogears 20th Anniversary Concert -The Beginning and the End-. The track is one of the tracks playable in the Nortune jukebox, under the option 'Requiem'.

The track plays as the music in the following cutscenes:
 * The lights come on in the Nisan Mausoleum, revealing Andvari.
 * Citan talks with Yui before leaving for Solaris.
 * Lacan speaks with Krelian about getting more paint and Krelian's newfound interest in nanomachines (flashback).
 * Elly brings Fei into her home in Solaris. (The music continues as the area theme until Elly's father returns, except for when Elly tells Fei about her biological mother.)
 * Elly's mother tells Elly that she should live her life as she chooses (flashback). (The music continues as the area and cutscene theme until the flashback ends.)
 * Elly successfully attempts to reawaken Fei (who was at the time controlled by Id) on the deck of the Yggdrasil III.
 * Fei and Elly both independently narrate how they had dreams of past lives, especially of Lacan painting Sophia's portrait.
 * Fei and Elly reunite on top of Taura's house.
 * Emeralda says that she wants to go with Elly to the Mass Driver Facility.
 * Krelian tells Lacan that he's studying from Kim's research journal (flashback).
 * Ramsus overcomes his feelings of low-self-esteem, and Fei states that he wishes to have a friendly fight with him after the end.
 * Emeralda turns into her older form in the ruins of Zeboim. (The music continues as the area theme until the Gear-accessible region is reentered.)
 * Fei and Elly reunite after Urobolos is defeated.

Intangible Treasure - Orchestral Version -
Intangible Treasure - Orchestral Version - is a remix of Unstealable Jewel. It is Track 4 on the -MYTH- The Xenogears Orchestral Album CD and track 3 on the A-side of the vinyl release.

Trivia

 * 'Radical Dreamers ~Unstealable Jewel~' from the music of Chrono Cross (which was also composed by Mitsuda) has this track's title as part of its own. (The pieces are otherwise unrelated.)