I have a 2 year old sink. Marble top and put new Kohler faucets in same time. There are hair line fractures (3) coming from under the hot water faucet on top of the sink. And under the sink the hot water faucet is badly rusted(with no leaks) I think this is going to be a fight with the company that sold me the sink top. So I am trying to gather all the info I can to argue my case. Any ideas out there would be gratefully appreciated.

Unfortunately marble is very delicate and CAN crack. This is not the best choice in counter tops no matter how hot an item with decoractors. Choose a different counter top material that is not so easily cracked. The same thing would have happened to granite as well. Had you dropped something on the countertop it would have cracked it also. The heat from the hot water faucet cracked the marble. Marble is basically stone and should not be used where there is too much heat involved. Good old formica looks crappy but is a lot more durable in the end for bathroom use.