Gemstone beryl. Gemstone pricing and value are governed by factors and characteristics on the quality of the stone. These characteristics include clarity, rarity, freedom of defects, beauty of the stone, as well as the demand for them. There are different pricing influencers for both colored gemstones, and for diamonds. The pricing on colored stones is determined by market supply-and-demand, but diamonds are more intricate. Diamond value can change based on location, time, and on the evaluations of diamond vendors. There are a number of laboratories which grade and provide reports on gemstones. Each laboratory has its own methodology to evaluate gemstones.
Prong setting shapes, depending on the shape of the gemstone, the size of the gemstone, or whether or not the gemstone is faceted or cabochon shaped. Common shapes of heads used in stone setting include round, oval, emerald cut, princess cut, marquise cut, pear shaped and trillian cut. V-shaped prongs are recommended for a marquise-cut or pear-shaped stone, while flat prongs are recommended for a flat-cut emerald. A prong setting holds the gem securely while allowing the gem to be struck with more light and from more angles, increasing the brilliance of the gemstone. A prong setting offers less protection to the