- For tough stains that appear to be just on the surface of the granite--marker, for example, or ink from a broken pen--start by applying hydrogen peroxide on the spot and scrubbing it gently with a clean cloth. If that doesn't work, try the same thing with acetone. (Make sure to ventilate the room.) If the surface stain is still present, make a thin paste of bleach and flour, spread it over the stain, let it sit for an hour, then wipe it up.
- For organic stains such as wine that have penetrated the surface and can't be scrubbed out, you can attempt to lift it out with an overnight poultice of baking soda and hydrogen peroxide. Put 1/4-cup baking soda in a bowl, and add the hydrogen peroxide slowly, working it with a spoon until you have a paste of about the consistency of oatmeal. Cover the stain with the paste. Lay a damp washcloth over it and let it sit overnight. The next day, scrub with the washcloth and thoroughly rinse the area.
- Oil stains can be left on your granite countertop by salad dressing, peanut butter, and many other foods, and can be the toughest to get out. Take several paper towels, fold them to the size of the stain, and soak them in acetone. (Wear rubber gloves and ventilate the room.) Lay the wet paper towels over the stain. Cover them with plastic wrap. Let it sit for up to 48 hours, then remove the towels, and check the stain. Repeat if necessary.