Three Auraliths have I set upon this land. Protect them and the Stones they bear, For all auracite is born of the Auraliths, and it is through these Stones I grant my power unto you.The Canon, Book of Stones, Canto XII
The auralith are objects of great power in Final Fantasy XII: Revenant Wings, objects of legend in The Canon. There are three auraliths scattered around Lemurés, and it is their power that sustains the sky continent. All auracite comes from the auraliths.
Feolthanos uses the auraliths to drain the aegyls' anima reducing them to cold and emotionless beings who feel neither hatred nor happiness. The stolen anima is locked in the auraliths and can manifest as Yarhi.
The auraliths sustain an alternate dimension where the Yarhi live, and pieces of auracite can be used to summon the Yarhi to the world of living, but doing so drains the summoner's anima, little by little, the more they summon. After Feolthanos steals Mydia's, a feol viera, anima, he turns her into the Judge of Wings and orders her to drain all of the auraliths' power and use the power to destroy Ivalice.
The First Auralith
Tormelados, Isle of the Megalith, is an aptly named island, as it holds the first auralith that the party encounters. At the base of the Megalith lies the Fane of Tehp Qul, a sacred shrine erected by the aegyl to protect the auralith within. Upon the party's arrival, Sky Pirates have already infiltrated the Fane and blocked its entrance.
Vaan sneaks through the guards and unlocks a secret passage for the rest of the party to follow. In the inner chamber, the party has their first encounter with the Judge of Wings, who summons Shiva to distract the party. After Shiva's defeat, the Judge drains the auralith of its power and it shatters.
The Second Auralith
The isle of Arda, Heaven's Pillar hosts the second auralith, deep within the Ymir Qul Underground. Vaan and the party head here after Fran tells them she last saw Balthier approaching the area. After escorting Fran to the Underground, they find Balthier alone in the Auralith's Cradle, surrounded by the Judge of Wings and a troupe of Yarhi, including the scion Mateus.
Upon defeat, the Judge flees. Balthier does an about-face and destroys the second auralith using the machine the Judge had set up. The auralith's destruction frees some of the aegyls' captured anima and sends Vaan and the remainder of the party to the dream world of the Yarhi, Lesrekta, Isle of Illusions.
The Third Auralith
The final Auralith is the most sacred relic in Lemurés, located in the Keep of Forgotten Time. Feolthanos himself is the final auralith, and the party must defeat him to release the souls of the Yarhi and return the anima of the aegyl.
After the auraliths' destruction the sky continent pf the Lemurés falls apart, the aegyl gain back their anima, and the Yarhi disappear from the world.