Precisely, Lunaire. The firmament doesn't shatter, it fades. Slowly deteriorating, much due to the incoming contaminants from the outer world.

I must ask, Lunaire, Estylwen, do you see how neatly the two characters you've created fit together? Avis' uncle is a mine worker, Ivy's father, a researcher in the field of renewable energy. One could presume that somewhere along the lines, they met and perhaps Orin somehow obtained a stone that Avis' uncle discovered. Maybe he was ordered or swindled out of it, either way, maybe he stowed a fragment of it in the airship he left to his niece?