Sapphire help: vendor says heat only, AGL brief says additional testing needed to confirm no diffusion

[sunandsky]

Hi all - you are all super amazing and I've learned so much here, thank you. A friend just bought a sapphire that the vendor listed as heat only, but the AGL brief says heat, then under additional it says " further testing needed to confirm no diffusion" (or something similar, I'm paraphrasing slightly). She's ok with heat but not diffusion. She's thinking of returning it, but wanted to check first to see if there's something here that would explain this?

thanks so much everyone!

 

[Bron357]

There can be some indicators visible under magnification but unfortunately the definite test for diffusion treatments is spectrograph analysis.
I think the AGL statement is more to do with the fact that heat treated sapphires can also be diffusion treated to improve colour. Their basic level testing aka a Gem Brief is not a comprehensive report so it’s more a “disclaimer”, not that they are suggesting that diffusion treatment is likely.
Depending on the cost of the Sapphire it may be prudent to pay the extra for a full report.

 

[minousbijoux]

AGL is indicating that it must undergo additional testing to determine whether it has been more invasively treated than just heating. I would definitely take this as a caution, as this is not something they say on all corundum Gem Briefs.

 

[sunandsky]

There can be some indicators visible under magnification but unfortunately the definite test for diffusion treatments is spectrograph analysis.
I think the AGL statement is more to do with the fact that heat treated sapphires can also be diffusion treated to improve colour. Their basic level testing aka a Gem Brief is not a comprehensive report so it’s more a “disclaimer”, not that they are suggesting that diffusion treatment is likely.
Depending on the cost of the Sapphire it may be prudent to pay the extra for a full report.

AGL is indicating that it must undergo additional testing to determine whether it has been more invasively treated than just heating. I would definitely take this as a caution, as this is not something they say on all corundum Gem Briefs.

Hi @Bron357 and @minousbijoux, thanks so much. It's been a disappointing experience - it's a PS-recommended vendor, and when my friend indicated she would return it, the answer was that it was "unlikely" to have undergone diffusion treatment. If that had been disclosed (that it's unknown, rather than stating that it hadn't), she wouldn't have bought it. She's now out almost $500 for shipping and customs fees; if she can get the customs back it's still $250.

 

[prs]

If it was a yellow sapphire that might have been a red flag to AGL. I know a lot of yellow sapphires are diffusion treated, and when disclosed, they are priced at less than 10% of an untreated stone.

 

[2Neesers]

What year was the AGL report issued? I seem to recall reading in an older thread that at one point in time AGL didn‘t have the equipment that test for that. They would have to send it out to another lab to do that testing, only when requested and for an additional fee. If the report is older, that might be why it’s mentioned. I should also mention that Maria at AGL is very helpful if your friend wants to call to find out more info regarding the comment on the report.
eta: I found the thread https://www.pricescope.com/communit...-about-testing-for-diffused-sapphires.159575/

 

[sunandsky]

If it was a yellow sapphire that might have been a red flag to AGL. I know a lot of yellow sapphires are diffusion treated, and when disclosed, they are priced at less than 10% of an untreated stone.

What year was the AGL report issued? I seem to recall reading in an older thread that at one point in time AGL didn‘t have the equipment that test for that. They would have to send it out to another lab to do that testing, only when requested and for an additional fee. If the report is older, that might be why it’s mentioned. I should also mention that Maria at AGL is very helpful if your friend wants to call to find out more info regarding the comment on the report.
eta: I found the thread https://www.pricescope.com/communit...-about-testing-for-diffused-sapphires.159575/

@prs and @2Neezers, thanks very much. It's not yellow, and the report was from 2017 - I'm off to check out that thread!

 

[PieAreSquared]

I was thinking of this (newer) thread:

Would you get GIA or AGL for colored gemstones?

I recently posted a thread regarding star ruby and was advised by kind and knowledgeable PSers to get a lab report. I tried to search the forum for previous threats regarding lab reports but wasn’t able to find the answer. Would there be an advantage to getting GIA or AGL? Both the same?

www.pricescope.com

 

[arkieb1]

What colour is the sapphire? If it is blue the vendor is correct blue sapphires are rarely diffused..... it's much more common in oranges and yellows.