When a gemstone is desired to be used in jewelry, it is cut depending on the size and shape of the rough, as well as the desired piece of jewelry to be made. As a rule of thumb, a cut gemstone will reduce the mass (described in the carat) by about 50 percent. Meanings of carat or karat: In the gem business: Carat (mass) is a unit of mass for gems. ...

Typical cuts include: Brilliant Bullet, Brilliant Straight Baguette, Brilliant Tapers, Brilliant Trapezoid, Bullet, Calf, Cushion, Emerald Step, Heart Brilliant, Kite, Moon, Oval Brilliant, Pear Brilliant, Princess, Radiant, Round, Square Emerald, Tapered Baguette, Tapered Bullet, Trapezoid, Trilliant or Trillion, Marquise, and Briolette.

There are several techniques available to work with gemstones. Specifically, sawing, grinding, sanding, lapping, polishing, grilling, and tumbling.

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