[thejeff]

Well, with Earthpower he's a E6 mage, so he could use them in 2 turns. I can't remember how many gems Curse of stones cost, but if it's 3 as well, he should be able to use 4 gems for that and for Earthquake, leaving him with 2 -- not enough for the second earthquake.

That's assuming I'm remembering the rule about only one more gem than the cost correctly. I think I've seen that not hold, if so, he'd happily use the full 6 gems casting Curse, then cast one Earthquake with the remaining 4.