Removing Tough Stains On Granite.

Here are some methods for removing stains on granite and other natural stones, basing the method on the type of stain.
General Stains
Mix a cup of flour, 1-2 tablespoons of dishwashing liquid with water to make a thick paste. Put it on the stain, cover the area with plastic wrap, and let it sit overnight. Next day, scrape away the mixture with a wooden utensil, plastic or rubber spatula and rinse. If the stain is oil-based... such as grease or cooking oil... use hydrogen peroxide in the paste instead of dishwashing liquid.
Organic Stains
Stains that might develop from coffee, tea or fruit juices... try a mixture of 12-percent hydrogen peroxide mixed with a couple drops of ammonia. Work over the stain, then rinse and dry. Repeat if necessary.
Ink, Marker or Wine Stains
Use a lacquer thinner or acetone to remove ink or marker stains from darker stone or granite. On light-colored granite, use hydrogen peroxide for these stains. This can also work for wine stains. Wipe off and remove. Clean with a mild vegetable soap. Rinse with a damp cloth and dry. Repeat if necessary.
Alternative Methods
Mix molding plaster and pure bleach into a paste and spread over a wine, ink or other non-oil stain. Leave on for no more than 30 minutes, then remove and rinse.

You can avoid most of the above stains by simply cleaning up spills and accidents right away... don't let any of the above set or stand on your granite countertop. Additionally, here are some other tips and things not to do or use on your granite or other natural stones...

Do use professionally-developed cleaning products for stone and granite such as Tenax Stone Coutertop Cleaner. Otherwise...
1. Use coasters under all glasses, particularly those containing alcohol or citrus juices. Many common foods and drinks contain acids that can etch or dull the granite or stone surface.
2. Do not place hot items directly on the granite or stone surface. Use trivets or mats under hot dishes and placemats under china, ceramics, silver or other objects that could scratch the surface... granite and most other natural stones are very hard and durable, but why take chances?
3. Do not use products that contain lemon, vinegar or other acids on granite, marble or limestone. Strong detergents or corrosive liquids can dull the polished surface of marble or granite and should not be used.
4. Don't use abrasive cleaners such as dry cleansers, scouring powders, or 'soft' cleansers.
5. Do not mix cleaning products such as ammonia and bleach together - the result is toxic.