Help! We removed tile from our fireplace and discovered that it had been placed directly over the outer portion of the firebox. Is this ok? We bought the house from a flipper and have found that he cut many corners throughout but I'm not sure what to make of this one. What should we do next? Do we tile over it again? Do we leave it exposed, just take off the mortar and grout that was left behind? Is there some other type of fireplace safe material we can place over the outer black part of the firebox?