Our travertine floor is developing black dull spots that won’t clean up. What can we do?

Travertine marble typically contains soft fillers that have a tendency to collect dirt. The black spots are probably dirt, and can be cleaned with heavy-duty cleaners. Apply a solution of cleaner and water and allow it to soak on the floor for several minutes. Do not allow the solution to dry. Scrub the floor with a soft deck brush or if the area is large use a floor machine equipped with a soft brush. Rinse the floor throughly and pick up with a wet vacuum. If this procedure fails to clean the black spots, it may be necessary to rehone the floor.