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What are the stones you have returned to Tan?

smitcompton

Ideal_Rock
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Hi All,

I recently bought 2 stones, one a heated blue sapphire that came with a lab report, the other a blue spinel. They both looked very nice in the video and photo and I asked the right questions about the stones before my purchase.
I was disappointed in both stones, each had a window which did not show in the least in the video and photo, and the sapphire was much less saturated than the video. The saphire GIT memo only said the stone was heated. I expected it to say there was no sign of diffusion.
Tan was easy to deal with, although he never mentioned the window even after I specifically asked him about it

A point has been made here that Tan has put up his prices. . That doesn't surprise me. If the demand increases, prices rise.
I suggest you ladies are the ones that cause the increase in price. You are probably more important to the vendors you love then you might think. I believe you should keep this in mind.

I finally figured out how these vendors on ebay get to keep 100 % positive rating. They ask you to cancel the transaction so you can't give them a negative rating. That hardly seems right.

I do agree that some of his stones look good. I saw Yingl bought a hot pink spinel (Meng..)sp and said it was as described. It was a beauty for a wonderful price. I wish I could have traded. Tanzanites are cheap and pretty nice if you bid. But TL you alone have put the price of Christiberyl up. Pricescoper do wield money power. Just my 2 cents.

Annette
 

T L

Super_Ideal_Rock
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smitcompton said:
Hi All,
The saphire GIT memo only said the stone was heated. I expected it to say there was no sign of diffusion.

Annette,
I believe if you want the stone LIBS tested (tested for a foreign element which would be indicative of possible diffusion), then it might be an extra cost and a more expensive GIT report. I have not confirmed this, but that's my suspicion. I rarely buy sapphires, and I am probably no longer going to buy them. The price of getting them tested to their full extent (testing for diffusion), is cost prohibitive for me, as I do not buy super expensive sapphires. However, I will say that if I did buy a super expensive sapphire, I would get the lab report with all the bells and whistles, preferably an AGL color grading report which includes full disclosure of treatment. If I did buy an inexpensive sapphire, I would want one that was deemed unheated, then you only need to pay for the $30 to $50 memo.
 

smitcompton

Ideal_Rock
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Feb 11, 2006
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3,272
Hi,

TL, that is good to know. I assumed they would test for that, otherwise what is the point of getting a memo. After all the vendor had admitted the stone is heated. I don't believe I asked for diffusion treatment testing specifically.

Sorry I mangled crystoberyl. Too much in a hurry to look it up. I hope this is right.

Annette
 

LD

Super_Ideal_Rock
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Annette - unfortunately not all Labs have the machinery to test for diffusion so we should never take it for granted that it'll be tested for that. :((
 

cushioncutnut

Ideal_Rock
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LD, if you end up pulling the trigger on the stone you inquired about, I am intrigued to know what you ended up buying! :bigsmile:
 

digitaldevo

Rough_Rock
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tourmaline_lover said:
deorwine said:
TL, I'd be interested in that thread on why you are not purchasing sapphires!

If this link doesn't scare you, I don't know what does. Page down and see the Ruby and Sapphire Treatment section. Heaven knows what the labs cannot detect. :errrr: My apologies to all the sapphire lovers out there, but I am really leary of corundum in this day and age.

http://www.cresla.com/Library/index.htm
Funny thing is though, almost every one of those treatments under sapphires and rubies can also be applied to many of the other stones out there, sadly. Beryls are routinely clarity enhanced with fillers, oils, resins, epoxies, etc. Tourmalines, beryls, quartz, kunzite, topaz, and a few others are routinely Cobalt-60 irradiated to achieve colors. I have personally seen clarity enhanced garnets, spinels, beryls(mainly aqua, emerald, and red), topaz, and yes even quartzes. While maybe some not quite as common as others, they are still out there sadly. The same methods to treat one stone can often be used, or modified slightly and then used, to treat almost every other stone out there. Treatments aren't so much the problem, at least not so much as the lack of disclosure. If everyone in the line of supply would just disclose the treatments there wouldn't really be an issue. :rolleyes: But that will never happen probably.

But, you should be leery of corundum, honestly! But you should also be leery of almost every stone out there! Being leery and cautious will serve you best in my experiences. If the deal is too good to be true, there is usually a reason.
 

LD

Super_Ideal_Rock
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digitaldevo said:
tourmaline_lover said:
deorwine said:
TL, I'd be interested in that thread on why you are not purchasing sapphires!

If this link doesn't scare you, I don't know what does. Page down and see the Ruby and Sapphire Treatment section. Heaven knows what the labs cannot detect. :errrr: My apologies to all the sapphire lovers out there, but I am really leary of corundum in this day and age.

http://www.cresla.com/Library/index.htm
Funny thing is though, almost every one of those treatments under sapphires and rubies can also be applied to many of the other stones out there, sadly. Beryls are routinely clarity enhanced with fillers, oils, resins, epoxies, etc. Tourmalines, beryls, quartz, kunzite, topaz, and a few others are routinely Cobalt-60 irradiated to achieve colors. I have personally seen clarity enhanced garnets, spinels, beryls(mainly aqua, emerald, and red), topaz, and yes even quartzes. While maybe some not quite as common as others, they are still out there sadly. The same methods to treat one stone can often be used, or modified slightly and then used, to treat almost every other stone out there. Treatments aren't so much the problem, at least not so much as the lack of disclosure. If everyone in the line of supply would just disclose the treatments there wouldn't really be an issue. :rolleyes: But that will never happen probably.

But, you should be leery of corundum, honestly! But you should also be leery of almost every stone out there! Being leery and cautious will serve you best in my experiences. If the deal is too good to be true, there is usually a reason.

+100! Totally agree. Buyer beware!

Thank you for your words about treatments to other gems. I'm was horrified to learn recently that garnets and spinels are being clarity enhanced. I believe this is a fairly new thing - is that correct? If so, can we rest easy that lovely gems we bought over 5 years ago are likely to be ok?
 

chictomato

Brilliant_Rock
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Hi there, so does it mean that if GIT memo states that is "natural Conrudum" with "no indications of heating" does it mean that the stone is free of all possible treatment? TIA!
 

T L

Super_Ideal_Rock
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DigitalDevo,
You are so correct about treatment. I've been accused of being paranoid about them, but I don't think many people realize how incredibly prevelant they are. My "list of stones to avoid" is getting larger and larger as a result. Corundum is a biggie though.
 

T L

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chictomato said:
Hi there, so does it mean that if GIT memo states that is "natural Conrudum" with "no indications of heating" does it mean that the stone is free of all possible treatment? TIA!

Supposedly, based on the opinion on the report. Currently, today, if a sapphire is unheated, it means no diffusion. However, who knows what other undetectible treatment there is. You don't need heat for irradiation for example, and it's often difficult t detect.

What's even scarier is that people will say, "well, if you know your dealer is honest, you should be okay." However, even the most honest dealers do not stay on top of treatment and/or can be duped.
 

cushioncutnut

Ideal_Rock
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tourmaline_lover said:
chictomato said:
Hi there, so does it mean that if GIT memo states that is "natural Conrudum" with "no indications of heating" does it mean that the stone is free of all possible treatment? TIA!

Supposedly, based on the opinion on the report. Currently, today, if a sapphire is unheated, it means no diffusion. However, who knows what other undetectible treatment there is. You don't need heat for irradiation for example, and it's often difficult t detect.

What's even scarier is that people will say, "well, if you know your dealer is honest, you should be okay." However, even the most honest dealers do not stay on top of treatment and/or can be duped.


It is unfortunate that the last statement has become so very true. You want to place your utmost trust in your dealer, however, he has to work so much harder himself to earn your trust.
 

virgoruby

Shiny_Rock
Joined
Oct 10, 2009
Messages
476
digitaldevo said:
tourmaline_lover said:
deorwine said:
TL, I'd be interested in that thread on why you are not purchasing sapphires!

If this link doesn't scare you, I don't know what does. Page down and see the Ruby and Sapphire Treatment section. Heaven knows what the labs cannot detect. :errrr: My apologies to all the sapphire lovers out there, but I am really leary of corundum in this day and age.

http://www.cresla.com/Library/index.htm
Funny thing is though, almost every one of those treatments under sapphires and rubies can also be applied to many of the other stones out there, sadly. Beryls are routinely clarity enhanced with fillers, oils, resins, epoxies, etc. Tourmalines, beryls, quartz, kunzite, topaz, and a few others are routinely Cobalt-60 irradiated to achieve colors. I have personally seen clarity enhanced garnets, spinels, beryls(mainly aqua, emerald, and red), topaz, and yes even quartzes. While maybe some not quite as common as others, they are still out there sadly. The same methods to treat one stone can often be used, or modified slightly and then used, to treat almost every other stone out there. Treatments aren't so much the problem, at least not so much as the lack of disclosure. If everyone in the line of supply would just disclose the treatments there wouldn't really be an issue. :rolleyes: But that will never happen probably.

But, you should be leery of corundum, honestly! But you should also be leery of almost every stone out there! Being leery and cautious will serve you best in my experiences. If the deal is too good to be true, there is usually a reason.

This statement is making me extremely nervous about buying any gem species...
I've only bought chrysoberyl and aquamarine from Tan so far; although they were described as untreated, should I be worried about possible treatments unbeknown to the seller? I know that aquamarine is commonly heated to get a better colour, but are there any possibility of other questionable treatments (eg irradiation) on aqua? What about chryso? Are there any common treatments on chrysoberyl that I should be aware of?

I didn't get any lab memo for my stones, as they were all inexpensive, AND because I thought chrysoberyls were less likely to be treated, thus didn't see any point in getting a lab memo. What do you think the odds of chryso and/or aqua being treated, ie how prevalent are the treatments on beryls?

(Please note that my concern re unknowingly buying treated stones is not specific to Tan's stores, but applies to buying gemstones from trusted sellers in general.)
 

T L

Super_Ideal_Rock
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Gemology is a very complex science, and treatment is just part of that. Like DigitalDevo, I have nothing against treatment as long as it's fully disclosed. However, asking EVERY vendor to do that is like asking ALL politicians to be honest. :lol: Whenever there is money to be made, you will find some deception. That is why I think it's important to use good vendors, and those that are educated and well versed on colored gems and can provide lab reports if necessary, and who have good refund policies. As for some gems, I just assume treatment, like aqua, most of it is heated, but in terms of the value, a heated stone doesn't make a big difference than an unheated stone. My suggestion to anyone looking for a particular gem is to educate yourself on the latest treatments/synthetics/simulants on that gem, and then buy. It's hard when there's so much selection out there, but I feel when you can focus on one gem species at a time, it helps. JMO.
 

chrono

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I wish there is an easy answer to give you but unfortunately, treatments are constantly getting more prevalent, difficult to detect, and more common place. I, too, have no issues with treatment as long as it is disclosed, then it is up to me if I can accept that level of treatment. However, my concern is more about those that are difficult to detect. Unfortunately, treatment is always one or two steps ahead of lab detection.
 

virgoruby

Shiny_Rock
Joined
Oct 10, 2009
Messages
476
Thanks, TL & Chrono. :read:

I am aware that you both purchased chrysoberyl from Tan recently (which btw are gorgeous) - would you mind me asking if you got a lab memo? If not, why not? Do you think it's a waste of time, given that 1) it's easy to detect treatments on chryso (N.B. I have absolutely no idea if this is true :???: ), and 2) Tan is competent/honest enough to disclose all the treatments on your chryso, if there was any? TIA! :halo:
 

chrono

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I did not get a lab memo on my chrysoberyl because there really isn’t any widespread treatment at the moment. My understanding is that irradiation has been around for the past few years on cat’s eye chrysoberyl to darken the colour although it might be possible for the faceted version as well. The good news is that the treatment is not commonly done and usually produces the extremely bright neon yellows. I have also heard that chromium is now diffused into chrysoberyl as well but this is currently only done in labs for scientific research. At this point, it is too expensive and difficult to diffuse to make it marketable as a widespread treatment process.
 

T L

Super_Ideal_Rock
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The below quote is what I've heard from a gemologist I know that makes it his duty in life to check for the latest and greatest treatments. I will not say his name as I may be violating PS rules if I did. However, I will say that, in hindsight, treatment is becoming so widespread and crazy, that probably at some point, you should get a lab report with any gemstone of signficant value to you (significant value has different meaning to different people).

Regardless, some treatements are not detectible, like irradiation, and it is important to educate yourself on which stones are typically irradiated, and just avoid them, or look for the tell tale inclusions indicative of natural untreated material. For example, natural color rubellite typically has needles and other inclusions, but much of it is heated and/or irradiated. Therefore, if you see a large clean stone, that's a red flag to me, although it could still be natural in color, but you may never know 100% for sure unless you saw it being dug up. My opinion would be to just avoid very clean rubellite completely. I personally have decided to avoid all of it (clean or included).

When I did buy my chrysoberyl, I had thought they were untreated and that's what I read everywhere. Well, guess what, I was wrong. I did not get a lab report as a result, but if it was irradiated, the lab wouldn't be able to tell anyways. As always, many people will say they trust their vendor, but even the most honest and best vendors can be duped. My comments have no direct correlation to what I feel about Tan, as I do think he is an honest vendor.

Quote:
Chrysoberyl is typically only irradiated, at least as of a few years ago, in its cat's eye form to darken some super light colors. I have also heard of Cobalt-60 irradiation being down on faceted goods. I do NOT think that either of these treatments are extremely widespread though.

Now, believe it or not, they have also diffused Cr3 into chrysoberyl as well. But this is only in labs and for scientific research, not something that I am aware of ever becoming easily and cheaply enough done to become widespread on the gemstone market. Nor have I heard of any gemstone treaters doing this, just some research laboratories for other things. So, no worries there yet.
 
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