Originally, and still strictly, the top metal rim or setting edge of a finger ring that is usually extended to surround the cavity which holds the stone or other ornament.
In modern usage, it is often loosely applied to all or part of the setting of the ring, including the set gemstone, or other ornament in lieu of stone, e.g. the seal of a signet ring.
The French term is chaton. The former name for 4 of the lozenge- shaped facets on the crown of a brilliant, all having their apex touching the gridle and extending up to touch the table.
The 4 bezels (also formerly called 'templets', alternating with 4 similar adjacent quoins (lozenges), were usually considered together as a group of 8 templates, the only difference being their orientation to the stone and the direction and sequence in which they were ground. All such lozenge-shaped facets are now each called a kite facet or main facet.
The bezels are the first facets to be ground after the table. Bezel facets in varying shapes and numbers are on some stones of other cuts. The metal rim or band around the top of a box, such as a snuff box, upon which the lid rests. The part of a cut gemstone that is above the gridle, now more properly called the crown.
From: An Illustrated Dictionary of Jewelry, autor: Harold Newman, publishers: Thames and Hudson