Every week someone’s new internet “bargain” comes in for appraisal and every week I shake my head over the blatant misrepresentations out there on the web, particularly e-bay.
Much of the public thinks that any official-looking “appraisal” validates an item’s authenticity and value. WRONG. I routinely see fraudulent grading and value statements up to ten times a realistic retail value. The money spent is often close to my appraised value, meaning you got what you paid for but no bargain.
There seems to be no end to the number of “labs” creating paper for some unscrupulous jeweler (yes, most of the sellers aren’t individuals but within the trade). The “labs” ought to be taken to task as well as the sellers who know the real value of what they sell.
It really hit home a few months ago when I got a call from an individual who was buying something on e-bay with an “NGL” certificate. Since I had not dealt with the stated jeweler and do not do “presale” appraisals for the trade, I was obviously curious. Well, National Gemological Laboratory had provided the document (I have seen several more since) and either I am losing my gemological bearing, or they grade two to three grades higher than GIA standards!
But I can only look at one case at a time. There are several reputable dealers on the internet—they have web sites (not just e-mail addresses), customer support, return privileges, etc. There are a couple of old adages I would like to leave you with. “There’s one born every minute” and “If it’s too good to be true….”


I am getting really tired of seeing “certified” diamonds and pre-sell appraisals that don’t stack up to the long established standards of the Gemological Institute of America (GIA). Appraisers who advertise their Graduate Gemologists (G.G.) credentials should follow the rules they were taught, whether appraising for the manufacturer, jeweler or consumer.
Ideally, an appraisal is prepared for the owner of the jewelry, with accurate grading and a realistic value for insurance purposes. Nowadays though, jewelers – both traditional and internet, are relying more and more upon appraisals prepared in the interest of selling the item appraised.
These “pre-sale” appraisals are everywhere, even on modestly priced articles and are often supplied by the manufacturers. Don’t get me wrong, I think up-front representation is great, (we started doing similar preliminary reports twenty years ago) but what I am seeing are reports which are more “jeweler friendly” than gemologically accurate. And the values attached tend to be consistently generous (at least compared to the values we follow).

Loose diamonds, too
The sale of loose diamonds on the other hand, usually involves no value – just grading, and that is where some very blatant misrepresentations have come into play.
Unfortunately, obtaining a pre-certified diamond doesn’t guarantee you are getting what the paperwork says. We do a fair amount of appraisals involving verification of pre-existing reports where we check for authenticity and accuracy.
We have uncovered many instances of inaccurate grading if not downright fraud from world-recognized laboratories as well as look-alike “labs” offering bad reports on rice paper.
The remedy is to always have your purchase verified during the appraisal process. We examine the previous document and if discrepancies are found, point them out. In the case of GIA and AGS verification, we will reference the document on our appraisal.
In the event of significant discrepancies you do have recourse. Since the jeweler owes you the quality they represented (even if they didn’t do the lab report) they must make good on your purchase. If you like the article but find it was misrepresented, you may elect to re-negotiate the sales price.
Either way, you don’t have to live with a misinformed purchase. Jewelry is supposed to make you happy, isn’t it?

What do you tell the customer who asks, “Has this gemstone been treated?”
Depending on your answer, that customer will either walk out the door with a bad taste for the jewelry industry or with a greater understanding and appreciation for the beauty of gemstones – and possibly the stone you were showing them.
The improvement of a gemstone’s color through a heating process is an everyday occurrence in the gem centers of the world. In Thailand, Sri Lanka, Australia, Brazil – everywhere a gem occurs, there is a treatment to enhance and stabilize the color and bring out the hidden potentials of a stone. Without it, there would be few examples of beautiful gemstones we are all aware of. Conversely, processes such as irradiation and diffusion create color that a stone had no potential to attain and are therefore treatments looked down upon in the trade.
There are several reasons to improve a gemstones color through heating. Light stones may be darkened, dark stones may be lightened. Asterism may be enhance or eliminated.
To accurately answer the opening question, a jeweler can only reply, “probably.” Since the process of heating a gem species occurs naturally, man’s introduction of heat is merely an extension of nature. In most cases, such treatment is not detectable by a gemologist and therefore cannot be disclosed on a laboratory report. Heating has most assuredly occurred, but the characteristics which identify heating are identical by both man and nature.
The process of heat treatment can only bring out characteristics that a stone already possesses. Pink sapphire will not become gem ruby. The color change in alexandrite will not be appreciably enhanced. Heat treatment has thereby gained acceptance in the jewelry industry. Heat diffusion and other techniques which create a coating to induce color, however, are not acceptable to the trade unless acknowledged and disclosed to the customer.
Heat treatment techniques vary with each gem species as temperature and time expose the important factors. In some cases, solutions are added to the process to facilitate coloration.
Examples of commonly treated gemstones include:

  • Aquamarine, out of the ground as green to yellowish-brown beryl, when heated to 400-450 degrees Celsius to produce that familiar light to medium blue “aqua” coloration.
  • Reddish brown topaz becomes a salmon-pink or purplish-red.
  • Zoisite, which occurs as a muddy greenish-brown is transformed to beautiful highly pleochroic violetish-blue tanzanite.
  • Dark blue Australian sapphires are lightened, although a more difficult process, through prolonged heating. Light blue to near-colorless Sri Lanka sapphires gain color through extreme heating.
  • Dark green tourmaline is reduced in tone to a pleasing medium-green.

Heat treatment is not without its pitfalls. Sapphire is most often heated to just below its melting point, making the process all the more difficult. Much money has been lost through “overbaking” to a point of ruining a stone.
If you’re still stuck for an answer to a question “Has this gemstone been treated?” liken the process cookies – the dough’s OK, but wait til they come out of the oven!

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