From the loredump linked above on Corrupted Crystals:
Quote:Corrupted crystals are far more prevalent due to the recent destruction to the land caused by the fall of Dalamud. Severe loss of life or the death of the land, according to Erik, causes a violent separation of aether from its host. Usually, aether returns to the Lifestream and rejoins the Aetherial Plane before cycling back to the Physical Plane to become new life.So the explaination in the OP of the 'yellow' (corrupted) crystals is accurate, but incomplete. There are other reasons aether can be corrupted as well, including voidsent.