Colored Stone Grading

[valeria101]

Hm... yeah, is harder to take all those colors and different materials into account. After all, see how complicated the grading of just one gem (the diamond) got if really taken to hart, and this was a comparable straightforward case: a simple white mass qualified by optics and hardness, with inclusions always not desirable. However hue, tone and saturation are perfectly quantifiable (and communicable numerically online, just like those famed crown & pavilion angles) as are the optics of each gem material. As far as I know, the color factors are already scaled for evaluating* pricing colored stones: only the actual grades (ranges of positions on sclaes) are more loose. As for cut, hasn''t the same Russian company which produced the diamond cut grading software just came up with a version for colored stones? I am quite curious to know more (no time these days

) given how different the existing criteria are in colord stones. Also, I know that cut charts for colored stones are designed with the optical properties of the stones in mind (aside typical shape or the rough and such). In all these details it seems that there is great potential to put together buying guidelines... if not a grading system (which is probably not feasible given the true natural rarity of most gem-grade colored things). Any thoughts? PS: Unfortunately, even if available online, most material I mentioned is proprietary, so no cut and paste.