One of the most iconic tools of a stone mason is the square-tipped chisel used to break stone in a straight line. This video shows the centuries-old process of rock pitching.
Stone is polished by hours of work by a skilled craftsman. There is no "coating" that is applied. The beautiful, nearly permanent shine on memorials is created by a series of diamond impregnated pads, water, and a skilled craftsman. If the polishing process is done incorrectly, the stone can overheat causing the stone surface to prematurely crumble.