All of the spells directed at the gem function identically, in that they do exactly nothing, but melt away as if the gem simply weren't there. There's a definite sense of<em>potential</em>within the gem, but he'll quickly get the impression that throwing magic at it isn't the solution.<br/><br/>It'll take quite a bit of experimenting and playing with it, before he'll finally find the secret to using the gem; when drawing upon the magic to use a spell, if he guides the draw through the gem, it<em>amplifies</em>the power of the spell. Considerably. It takes a fair amount of practice to do this without it taking more time, but once he's adept at it, he can draw upon even some of his more powerful Epic spells, using far less power.<br/><br/>(In game terms, it would allow a sorcerer to cast a spell using a spell slot two levels lower, and has almost unlimited usage, though excessive overuse might damage it.)