[1] Agates and turquoise are usually cut this way, but precious stones such as rubies, emeralds and sapphires may also be.
[2][3][4] Many stones like star sapphires and moonstones must be cut this way in order to properly display their unusual appearance.
A bezel is a strip of metal bent into the shape and size of the stone and then soldered to the piece of jewelry.
Generally, a prong setting is formed of a number of short, thin strips of metal, called prongs, which are arranged in a shape and size to hold the given stone, and are 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 burr most often used is called a "hart bur", and is angled and sized for the job of setting diamonds.
A cup burr is in the shape of a hemisphere with teeth on the inside, for making rounded tips on wires and prongs.
A hole is drilled directly into the surface of the metal, before a ball burr is used to make a concave depression the size of the stone.
Some setters will set the stone into the concave depression, and some will use a hart burr to cut a bearing around the edge.
Then a beading tool – a simple steel shaft with a concave dimple cut into the tip – is pushed onto the bit of metal, rounding and smoothing it, pushing it firmly onto the stone, and creating a "bead".