Gemstones are first judged for their color while diamonds are judged more for their cut and clarity. This is even more true for emerald, rubies, and sapphires since they are rarely cut with modern meet-point faceting. This technique uses diagrams where the facets meet at a point and produce the best light return for a particular species of gemstone based on the refractive index. Almost all rubies, emeralds, and sapphires are cut commercially less concern for light return but rather maximize the yield of the expensive rough stones. It is also rare to find commercial cut stones with a polish that is better than 14000 diamond grit. American style faceting in contrast is usually polished at 50K diamond or higher. Modern oxides are in common use by custom cutters and provide a polish similar to 100K diamond grit.
One mistake that gemstone buyers make when looking at well cut stones is to be dazzled by the brilliance while forsaking the color. Don’t forget the color! Color is the number one criterion for judging colored gemstones. Our eyes naturally gravitate to the brilliant stone on the counter but brilliance will make light colored gemstones appear better than reality. Flip that stone on its back or look at it from another angle to get a better idea of the actual body color of the gemstone before the cut affects your perception. Brilliance or “fire” is important but should never trump color. Color is always the highest percent of cost in any gemstone. Once you’ve found a few gems with the best color then go and judge them for clarity, cut, and brilliance. You don’t need to give up brilliance or clarity but it should not be the first aspect to look for.
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