Q. What is the best method for removing rust marks from a white-marble fire- place slab? An industrial-grade cleaner has failed to do the job. Arthur M. Horowitz Highland Park, Ill.
A. Commercial janitorial firms usually are experienced in how to remove stains from masonry, it often being a touchy matter and more likely so in the case of white marble.
Check with an experienced local commercial janitorial company for its inspection and recommendation. First test in a small area for results.
One experienced firm making stain removers is ProSoCo Inc., 1040 Parallel Parkway, Kansas City, KS 66104. The phone number is: (913) 281-2700.