Cleaning Granite Countertops

I have a fireplace hearth made of the same thing. They do make products to clean and polish granite now a days, but I have never tried them. They weren't around forty years ago when we moved into this house. I have always used warm water and a mild dish soap then, went back over it using a clean cloth and Lemon Oil. I let the Lemon Oil penitrate the surface for about 20 mins or so, then re-wipe with another clean soft cloth. That really does the trick to make the hearth look spanking new. I also use Lemon Oil on my kitchen formica counters, and Mom's fifty year old black stove. I do the stove every single day and it also looks spanking new.