Does anyone know what the best treatment is for keeping a black Virginia slate tile floor looking good? I only clean it with pinesol and water. Is it OK to use any of the commercial products such as Mop& Glo? I did try it on the brown slate flate rock work under the wood stove and it darkened and brightened them. I have been holding off doing anything to the kitchen floor until I found out what would be good but just never have the time to plan.