Quote Originally Posted by Brightamethyst View Post
Black and white magic still use environmental aether. It's why the elementals regulate conjury and white magic so carefully and why black magic is forbidden in most of Eorzea. Red, blue, and arcane magic all use the caster's personal aether. IIRC, summoners use environmental aether to create the egis initially, but once bound to a soul crystal they can be recalled using personal aether.
Just a small correction, Blue Magic draws surrounding aether as well;

Martyn: “The name’s Martyn, and today I present to you a wonder of the New World. I call it ‘blue magic’! Beyond the Indigo Deep live the Whalaqee, who have their own unique brand of spellcastin’. Like black and white magic, it draws on aether from our surroundin’s, but that’s where the similarities end, my friends.

Though I'm not sure if it's ever touched upon something or the other regarding eating the aether in a hazardrous way.