How do I clean the grout lines after polishing? The grout is black and the white powder residue is difficult to remove.

There are several ways to remove this residue. First try using a solution of stone soap and warm water. Apply this solution with a string mop and pick up with a wet vacuum. Next time you polish granite with black grout lines add a small amount of black powdered dye to your polishing compound. The black dye will color the polishing powder so that the grout lines will not turn white. Grout dyes are available at concrete supply houses or you can use unsanded black grout.

TIP Try adding a cup of ammonia to your rinse water to aid in clean up. Do not use too much ammonia and be sure to rinse throughly with clean water. Try buying odorless ammonia.