Hello and thanks for any help you can give me on this. I sealed a travertine floor with a hydophobic enhancing sealer about a month ago. The lady called about an area of concern, so I went to see the problem. It's an area about 3-4 sq. ft. of blackish stain, looks like its coming from below, like black mold. There is an attached picture of the area, the picture makes the area look lighter than it is but you will get the idea. the sink, referidgerator,and dish washer are no where near this area. whats your best guess, and how would you deal with the stain?