A common technique used in these cases is Diamond Abrasive Grinding.
This process uses a particular rotary machine with diamond pads underneath, hence the name. Diamond is well known for its strength and in this case the rotation of fine diamond particles has a polishing effect on the stone surface.
After this stage, when all the scratches and damages are not visible to human eye anymore, the surface is treated with a special product to enhance its shine.
Other restoration techniques are: Stone Sealing and Vitrification.
Natural stone is porous, which means that it will retain any liquid that gets spilled on it, which can leave a stain, depending on the type of liquid. All stone types should be protected in order to protect their natural beauty and prevent damages.
Stone sealing is an essential step whether you are installing or restoring any type of stone, in order to make sure that you are leaving your client with a surface that will keep its appearance for as long as possible, and will be easier to clean and maintain in the future.
Vitrification instead is a method that uses a chemical reaction between steel wool and a special chemical compound that only works on certain types of stone. Marble, granite, travertine and limestone can be vitrified because they contain calcium carbonate, but for example granite doesn’t so this procedure is not applicable.