GIA report for sapphire

[kenny]

I'm not impressed.
Seems to me AGL reports stick their neck out more when describing color, which influences price tremendously.

What is, Source type . . . CMT type II ?

GIA only mentions heating: So is heating the only treatment done to sapphires?

FWIW, here is the original listing for this stone:
http://cgi.ebay.com/6-33ct-GIA-CERT...Gemstones_1&hash=item563d8d2a81#ht_2310wt_917

Fear Not! I am NOT considering buying on eBay!

 

[vinkalmann]

Based on this PDF it means "Classic Metamorphic" (whatever that means), the II denotes possible countries:
* Kashmir
* Madagascar
* Sri Lanka
* Tanzania
* Vietnam (rare)

http://www.giathai.net/pdf/GIA_Corundum_7499_050307.pdf

 

[kenny]

Thanks.

Well I think we can rule out Kashmir.
If the owner suspected it was from Kashmir he/she would have certainly request origin research.
Kashmir seem to be more expensive origin.

 

[T L]

I'm not impressed.
Seems to me AGL reports stick their neck out more when describing color, which influences price tremendously.

What is, Source type . . . CMT type II ?

GIA only mentions heating: So is heating the only treatment done to sapphires?

FWIW, here is the original listing for this stone:
http://cgi.ebay.com/6-33ct-GIA-CERT...Gemstones_1&hash=item563d8d2a81#ht_2310wt_917

Fear Not! I am NOT considering buying on eBay!

For less exensive sapphires, most certificates like GIA suffice since they indicate the treatment level. I am in complete agreement with you for the quality of the AGL. It does denote the overall quality of the gem based on color, clarity and cutting, as well as treatment and any specifics on treatment. I wish other labs would raise the bar and follow their example.

All treatments that I know of which are performed on corundum require some heat. However, there is a big difference between heating to ward off some unwanted modifier (like grey) and heating to infuse filler or dye the stone, which are also performed on corundum. Beryllium diffusion can only be detected by very sophisticated and expensive equipment, and I belive the following labs are the only ones capabale of testing for diffusion:

GIA
AGL
SSEF
GRS
GIT

If you have a lab certificate from another lab and it indicates that the stone is heated, it might also very well be diffused. Be careful of the lab you pick and ensure it tests for beryllium or other foreign elements. If microscopic evidence indicates the stone has not been heated, then you can assume it has not been diffused or filled (rubies are routinely glass filled).

 

[T L]

Thanks.

Well I think we can rule out Kashmir.
If the owner suspected it was from Kashmir he/she would have certainly request origin research.
Kashmir seem to be more expensive origin.

Since a premium is paid for sapphires of Kashmir or Burmese origin, I would not accept a stone without a reputable lab certificate that includes origin.

 

[movie zombie]

BE-treated sapphires: you really don't want one.

i think it was easier swimming when you were contemplating that blue diamond!

mz

 

[chrono]

Tl has explained about the labs and treatment very well. For a premier stone, AGL full memos are the best and worth every dollar as they also grade colour quality whereas other labs shy away from it. Generally, if a sapphire is untreated, then all is well. Other treatments such as lattice diffusion usually require heat and not all labs have the equipment and capability of testing for it. So just because a lab memo states that the sapphire is heated, it doesn't mean that it has not been BE diffused.

 

[kenny]

So this stone may be BE diffused?

http://kashmirblue.com/Sapphire/Certs/p ... 10351.html

 

[chrono]

No, because it is unheated. Diffusion requires extremely high heat, to the point of almost melting the entire stone itself.

 

[kenny]

So I can be confident there is not treatment, enhancement (or any other term) today that flies under the radar of this level of AGL examination?

 

[chrono]

So I can be confident there is not treatment, enhancement (or any other term) today that flies under the radar of this level of AGL examination?

Yes, that is correct. If AGL lists it as unenhanced, then it has not been heated, diffused or whatever else.

 

[kenny]

Thanks Chrono.

I started to slog through that pinned long list of vendors.

Does anyone know if another vendor sells Sapphires judged by AGL to be of Kashmir origin?
Also, I did a search for any complaints about the vendor KashmireSapphires and found none, but I'm not sure if that's because the new PS 2.0 search function is still buggy.

Any opinions about this vendor?

 

[Arkteia]

11 K seems to be low for a Kashmir sapphire. So what is the catch here?

 

[kenny]

11 K seems to be low for a Kashmir sapphire. So what is the catch here?

Here's one for $270 that the vendor says is "guaranteed Kashmir".
Perhaps this vendor is not to be trusted?

http://kashmirblue.com/Sapphire/Certs/profileLG10322.html

This one is also "guranteed Kashmir" for $275.

http://kashmirblue.com/Sapphire/Certs/profileLG10207.html

Someone wrote in another thread that not every Sapphire that comes from Kashmir is the best example of what comes from Kashmir.

 

[Kismet]

11 K seems to be low for a Kashmir sapphire. So what is the catch here?

Here's one for $270 that the vendor says is "guaranteed Kashmir".
Perhaps this vendor is not to be trusted?

http://kashmirblue.com/Sapphire/Certs/profileLG10322.html

This one is also "guranteed Kashmir" for $275.

http://kashmirblue.com/Sapphire/Certs/profileLG10207.html

Just being from Kashmir doesn't automatically make it a nice looking sapphire. I haven't heard anything good or bad about that vendor.

I think http://www.rwwise.com has some Kashmir (and "Kashmir") sapphires. Although the certificate is from AGTA and not AGL.

 

[T L]

11 K seems to be low for a Kashmir sapphire. So what is the catch here?

Here's one for $270 that the vendor says is "guaranteed Kashmir".
Perhaps this vendor is not to be trusted?

http://kashmirblue.com/Sapphire/Certs/profileLG10322.html

This one is also "guranteed Kashmir" for $275.

http://kashmirblue.com/Sapphire/Certs/profileLG10207.html

Someone wrote in another thread that not every Sapphire that comes from Kashmir is the best example of what comes from Kashmir.

Like Kismet said, not all Kasmirs are good, and that one is lacking in saturation and very small. I think they're charging a fair price for something that is not the best color, regardless of the origin. I think that's an honest practce. You can purchase a lab report with it as they provide that option. I suppose for someone wanting the origin without the price, that stone would be a good candidate, but it's not fine color.

 

[chrono]

11 K seems to be low for a Kashmir sapphire. So what is the catch here?

There is no catch. It seems a fair price for the lower quality as compared to others on that website. While a particular place may be famed for producing super fine gems, it also produces some average and dud quality stones. So in this particular case, this Kashmir sapphire isn't as fine as the rest, hence the advice to buy the stone and not its origin. However, there is usually a premium on the origin, regardless of the quality.