Not sure where else to post this, though it's not a kitchen matter in my house. I have antique moorside limestone floors in my mud hall. The tiles are huge, uneven, some partially cleft. They have faded to a gray that looks dirty constantly and only the smooth areas are a nice black. I know limestone fades and would like to restore mine back to black, but have never used an enhancer and am concerned how the grout will hold up to this. Any thoughts are greatly appreciated.