Evaluating Gemstones

Although the components that go into judging a diamond’s quality are well defined, there is no such agreed upon system when it comes to colored gemstones. Currently, even a six-year-old, given a bit of training, could be qualified to become a gemstone appraiser. Dealers are hesitant to accept anything like the diamond trading standards as that would mean they would lose some of their power and have to send gemstones away for a lab analysis. But the benefits of such a system are obvious, as it would certify the quality of a stone.

One proposed way of judging a gemstone is to examine its “three c’s”: cut, clarity, and color. Even with accepted standards, the cut would still be a subjective grading, because it involves the aesthetics of the stone, like its shape or the style of its cut. Clarity is about the inclusions within a gemstone, that is, anything caught inside of it that mars the design or affects the durability.

The final criteria, color, involves three main components. These are the hue, the saturation or richness, and the darkness. Stones that are too light or dark are not worth as much as those falling in the middle; similarly, the saturation level should fall more toward the middle of a chart.

A number of factors can influence the color, such as the cut, inclusions, the background on which the gem is placed and the uniformity, causing headaches for the dealer who would try to examine the color by eye. Color measurement devices are taking on a greater importance in the industry as a result. In time, they may even be able to provide objective ways of judging a gem.