stain on granite table top

[granitestain]

I purchased a black granite table from Ashley Furniture in 2004. I had a tenant who left a couple of circular stains on it which appear to be from a cooking pan lid or a glass?  There are other smudges, they appear whitish. I am now selling this table and want to tell the buyer they may be able to remove this stain, only how? Also, where in Minneapolis would they be able to buy a product to do this? Thank you kindly!

[Mark D.]

Here is the process which was recommended by Tenax:
First you have to clean off your oil deposits and sealers with an alkaline solution. Caustic soda works great for this and you can get it very inexpensively from a pool supply store. Keep the granite moist with this allowing it to penetrate the stone. You might try wrapping it with paper towels after the application to keep the solution on the stone. This solution will dissolve waxes, oils, even sealers!

After cleaning the granite make sure it is fully dried before going to the next step, which is resealing the granite.

Mark