People perform stone engraving to carve and etch decorative designs and lettering into hard stone surfaces, such as marble and granite, and on softer stones like soapstone and alabaster. A person will use such tools as rasps to shape stones, chisels and hammers to rough out the shapes and lettering and polishers to bring a smooth, glossy quality to the stone.
Hand tools used in the crafting of stone with decorative designs include chisels made of hardened steel. These chisels work on softer types of stones as well as marble. Carbide-tipped chisels work best with harder types of stone. When using chisels, a hammer is required. Care must be taken to use the proper hammer with the proper chisel. Hammers with hardened steel heads should be used only with chisels with untempered ends. Metal fragments can be created when striking a hardened steel chisel with a hardened steel hammer.
Power tools can effectively carve small details into stone with ease. A die grinder is used with softer stones. This power tool can get into holes and crevices easier than most tools when equipped with diamond-coated burs. Another type of power tool is a grinder with a diamond cup wheel. This tool allows for smoothing rough surfaces.
Pneumatic tools rely on an internal piston driven by compressed air. Instead of using a regular hammer with a chisel, a stone engraver can use a pneumatic hammer with the chisel for general carving. An air compressor must be used with every size of hammer involved with the work. The compressed air, which flows through a hose, is regulated by a valvelike device called a stopcock.
Polishing the stone is the last task after finishing the engraving. Types of polishing tools include wet/dry sandpaper and pneumatic polishers that use water to wash away dust particles. Sandpaper is commonly used on softer stones while the pneumatic polisher can be used on large, flat and harder stones.