Use: A few drops of dishwashing liquid and warm water.
Tools: A cloth, sponge, or mop.
Tips: Sweep or vacuum up grit regularly. Rinse floors and dry with a clean cloth. Apply a sealer, available at stone dealers and home centers, to countertops every year and to floors every two years to prevent deep stains. Don't use abrasive cleansers, which can scratch, vinegar, or lemon-based cleansers, which can etch the surface.
Tough stains: Use a ready-made poultice, available at stone dealers.