The two most common problems, many home owners’ have with Natural Stone are:
Scratches, how to repair and avoid them? 

What could scratch Natural Stone?

Okay, all Natural Stones can be scratch. To scratch a stone, normally it will take something harder than the actual stone in order to scratch it. For example, a piece of Granite or Marble would scratch a piece of Soapstone, since Soapstone is a softer stone. But, Soapstone would not scratch your Marble or Granite. If you have Natural Stone tile floor, it can be scratched from foot traffic. Dirt, sand, and grit from your shoes are an abrasive to stone flooring. This is why it is recommended to use rugs, or mats near entry ways.

Scratches in Granite and other Natural Stone can and do happen. Question is, can they be repaired and How? This will depend on the type of stone you use, where the stone is located, and the depth of the scratch.

Soapstone scratches are one of the easiest to repair. For light scratches, put mineral oil on a paper towel or soft cloth, and apply it using medium pressure. If the scratches are deeper, use 100-grit sandpaper and sand it out. And then, apply mineral oil.

Granite and Marble scratches are not repaired quite as easily. If your Granite or Marble Countertops are scratched, most likely you will need help from Stone Care Professional (fabricator). They would have to come in with an electric machine and sand the scratch out using diamond pads. In some cases, it may be necessary to re polish the whole surface in order to mach shine. This would make your stone like new but it is very expensive. Surface polishing is a very difficult thing to do. It's considered an art in the stone business.

Can I Repair Scratches myself? Is there any possible Quick Fixes?
Try buffing slight surface scratches with dry #0000 steel wool.

If your Countertops (stone surfaces) are made from dark stone like "Arabian Black" or "Absolute Black Granite", it may be possible to small scratches yourself by using a black permanent marker or a paint marker. Color in the scratch and then wipe off the area with denatured alcohol to remove any excess color. This method isn't repairing granite or stone scratches. The scratch becomes visually not present.
If the scratch disappears when wet, you may be able to hide scratches by using a good quality stone color enhancer.