Per “Orange Diamond Buying Guide" I’ve a question, please. Is it possible for a vivid yellowish orange, as graded by GIA, to be essentially color-indistinguishable from a vivid orange without extensive testing (e.g., FTIR) to determine precise composition? I assume GIA is conservative: if a non-subjective/scientific review shows possible production of even the smallest amount of yellow, a report must say FVYO, I assume, even though one can’t see yellow, per se. Is that a possible scenario? Thank you!
Hi Chris!
Welcome to the community!
Are you referring to this article here on IGS?
As for GIA grading criteria, there are several members who specialize in diamonds and they can answer your specific questions better than I could.
If you haven’t seen the business section of IGS, there are several companies/individuals who you could reach out to, directly.
Cheers!
Hi, Troy. Thanks for the reply. Yes, that was the article that inspired my question. Before I reach out to other parties (good idea), I’ll give this a few more days to see whether others weigh in here. Thanks, again.
This article by the GIA may be of some help… Google search will also bring this one up.
Naturally Colored Yellow and Orange Gem Diamonds
GIA
https://www.gia.edu › gems-gemology › summer-2020-…
](https://www.gia.edu/gems-gemology/summer-2020-naturally-colored-yellow-orange-diamonds)
by CM Breeding · Cited by 19 — Yellow and orange diamonds colored by a 480 nm visible absorption band are nearly always type Ia and usually have low to moderate concentrations of A-centers, …
Hi, Steven. Thanks for sharing it. I had actually seen that. It’s fascinating. While it was very educational, it didn’t get me any closer to the notion of a “cusp” color rating, sadly. In my very imited experience, there is a very wide spectrum of colors for a diamond flagged as FVYO, some seemingly extremely close to FVO.