This part of the gemstone is utilised differently according to the setting.
The girdle of a gemstone refers to its widest point and is where the bottom of the crown meets the top of the pavilion.
Though it is normally a sharp point, on larger gemstones it sometimes has very small vertical facets applied. The term is only applied to faceted gems and not in connection with cabochon or tumbled cuts.
Typically, the girdle is where a gem is held when set in jewellery. In a channel, tension or bar setting, the girdle is held in a groove between the metal; in a prong setting the stone is held just above the girdle on the crown. In a bezel setting, the supporting metal is bent over the girdle all the way around the perimeter of the gemstone.
Often most gem cutting houses will not apply a high polish to the girdle as it is not necessary if the buyer is going to set the gem in either a channel or a bezel setting. However, just like Pearl houses who string their Pearls on temporary strands which are not intended for use in final jewellery, far too often you will see ugly, unpolished girdles in open jewellery settings, just as you will find Pearl necklaces on the market that still have their temporary strand precariously holding the piece together. As my company controls each step of the process, I insist that we always polish our girdles!
