How to Groove Marble

Mark the area of the marble that you'd like to groove with a pencil. If you wish to make a straight groove, tape a steel ruler to the surface of the marble, flush with the line you made.

Place the tip of the point chisel on the end of the line farthest from you and pull the point toward you. Apply a little pressure to the tip and score a very light line along the pencil mark you made.

Place the tip of the point chisel at the end of the line closest to you. Position the point chisel at a 45 degree angle to the marble, with the hilt of the chisel closest to you and the point of the chisel pointing away from you. Hit the end of the chisel with a hammer. Continue to hit the end of the chisel, driving the point along the line you scored. Do this until the point of the chisel has reached the opposite end of the line you scored.

Place the tip of a tooth chisel, with a tip as wide as the groove you'd like to cut, at the end of the groove. Position the tooth chisel at a 45 degree angle to the marble and hit the end with the hammer. Drive the point of the chisel along the groove until it reaches the other end.

Repeat until the groove reaches your desired depth.

Choose a narrow rasp that fits in the groove. Insert the tip of the rasp in the groove and run it back and forth over the marble, softening and sanding the surface.

Sand your groove with 100 grade marble sandpaper. Switch to progressively finer sandpapers and continue to sand the groove until it is as soft and smooth as desired. The finer sandpapers will be indicated with higher numbers of sandpaper. These numbers go all the way to 3000.