Granite is porous and the porosity varies from stone to stone depending on the density of the stone. Porosity in the stone allows absorption of oil and grease from food spill on the counters. Since the stone is porous, it is possible to remove the stain by reversing the process. The process is simply reabsorbing the stain from granite to another material, and is called poultice. The stain removal process time depends on how deep the stain is in the stone.
A poultice can be prepared by using a base material like white chalk powder mixed with ammonia or acetone. Moisten the area with distilled water so it becomes easy for stain to come out. Make a thick paste out of the chalk with ammonia and apply a thick layer of ½” on and around the stained area. Cover the paste with clear plastic sheet and seal it with masking tape. Pierce few tiny holes in the plastic so it can breathe for moisture to escape. The drying out process is essential and that is what absorbs the stain out of the stone to the poultice. Always seal granite so it is protected from staining.
