Q. I just got a new granite kitchen countertop. I didn't know this, but my dish soap dispenser which I had near the faucet left a dark stain (circle) on the granite which is very noticeable. How can I get rid of this stain?
A. The soap has been absorbed by the stone from inside the hole and that particular area is soaked with it through and through.
First, you have to remove the soap dispenser. Second, make a paste with talcum powder (baby powder) and water of the consistency of peanut butter and you spread it on top of the stained area putting it down 1/4" thick or better, while going a good 1 inch all around over the stain.
Let it sit there for a week or so without touching it. After a week, remove the powder and see what happened. You may have to repeat the procedure more than once before all the soap will be drawn out.
Once you got rid of the stain, before you install the soap dispenser again...
1. make sure that there are no leaks from the connections of the dispenser, and...
2. see if you can have your fabricator or stone pro brush the inside of the hole (and possibly an area underneath it a couple of inches wide, with flowing epoxy. This will create a 100% seal. (No impregnating sealer could accomplish that, no matter what the advertising of the product says.)