Prong setting is the simplest and most common type of setting, largely because it uses the least amount of metal to hold the stone, thus showing it off to its best advantage. Generally it is simply some number of wires, called prongs, which are of a certain size and shape, arranged in a shape and size to hold the given stone, and fixed at the base. Then a burr of the proper size, is used to cut what is known as a "bearing", which is a notch that corresponds to the angles of the stone. The most often used is called a "hart bur" that is angled and sized for the job of setting diamonds. That bearing is cut equally into all of the prongs and at the same height above the base. Then the stone is inserted so that it goes into all of the bearings, pliers or a pusher are used to bend the prongs gently over the crown of the stone, and the tops of the prongs are clipped off with snips, filed to an even height above the stone, and finished. Usually a "cup burr" is used to give the prong a nice round tip. A cup burr is in the shape of a hemisphere with teeth on the inside, for making rounded tips on wires and prongs. There are many variations of prong settings—two prongs up to 24 or more, many variations involving decoration, size and shapes of the prongs themselves, and how they are fixed or used in jewelry. But the method of setting is generally the same for all of them.