darkeyes,
I think that would be really neat to have the rock of unprocessed Lithium. I just think that Lithium is a really neat element to begin with. I don't think you will fatten up, although I have talked with people who have lost a few pounds. I guess cause it is a salt, and adding an regular dose of it can cause you lose a weight, mostly due to lack of water then the body burning fat. (just guessing). Life seems to keep fighting the person, and bipolar just doesn't help the fight.

Good Luck,
adam