Here are the types of stain and what you can use to remove them.
1. For organic stains like coffee, soda, mustard, gravy, tea, etc., you may use Hydrogen Peroxide (30%-40% by volume)
2. For inorganic stains like ink, dyes, dirt, etc. you can use rubbing alcohol for ink; Hydrogen Peroxide (30%-40% by volume) for all others
3. For oil like any type of cooking oil, some mineral oils, butter, margarine, etc, you may use pure acetone (avoid using nail polish remover as different brands have different ingredients)
4. For biological stains like mold, mildew, etc., you can use bleach or MB-9
5. For metal stains (rust, copper, etc.) you can use iron-out (a white powder available at hardware stores)
Granite Countertop Fabrication Clearwater - www.stmgranite.com/