Magicite

However, the espers are already dying from the experiments at Vector, and choose instead to give their lives to transform into magicite—the crystallized remains of the espers' essences that form when they die and allow others to use their powers.

I can lead you out with my last ounce of strength. citation However, before her father's magicite shatters, his spirit informs her that by holding to the human side of herself, she may survive the passing of magic.

I'm to bring the Magicite remains of these Espers to his excellency!

It is only when we are reduced to Magicite that our abilities can be transferred in total..

The Returners reunite, now aware that the peace was a ploy for Gestahl to obtain magicite and the stone statue remains of the Warring Triad within the espers' now-unsealed land.