CIBJO releases Gemmological Special Report: considers process of separating measurable facts from opinion; See Gemological Articles below.
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 Post subject: Treated Tanzanite ?
PostPosted: Wed Jan 30, 2013 11:05 am 
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I'm hearing word of diffused Ziosite/ Tanzanite hitting the market in Thailand. It's not the coated stuff that showed up a few years back. Treatment all the way through.
Large quantities, cheap, all the same color.

Anyone seeing or hearing this?

Will keep you posted when I hit Tucson.

Tks,
360

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 Post subject: Re: Treated Tanzanite ?
PostPosted: Wed Jan 30, 2013 11:06 am 
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Where did you hear this?


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 Post subject: Re: Treated Tanzanite ?
PostPosted: Wed Jan 30, 2013 11:10 am 
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My Thai guy stopped by on his way to Tucson.

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 Post subject: Re: Treated Tanzanite ?
PostPosted: Wed Jan 30, 2013 5:11 pm 
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I guess your Thai guy is full of doodoo from the lone star state. Most of us know where this "infusion" idea is coming from and it is from someone that never set foot in BKK but is shopping on e-bay.

I was in Bangkok last weekend going through heaps of very good to top quality Tanzanite. To find a decent pair it took a couple of hours of hard work. Mostly because it was very difficult to find two stones matching in top color. So that there should be an abundance of Tanzanite in the same hue, tone and saturation is not true. If that had been the case the dealers would have presented a nice pair immediately as time is money, instead of letting us spend hours with their goods to pick out a couple of stones. But of course then we were not really looking at the cheap stuff.

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 Post subject: Re: Treated Tanzanite ?
PostPosted: Wed Jan 30, 2013 9:57 pm 
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Agree with Conny.

It's actually difficult to find top colour tanzanite in Bangkok. I've been there a couple of times over the past month or two and have been specifically looking for Tanzanite. I've literally seen hundreds of stones and out of those hundreds, there have been maybe 7 or 8 of various sizes that I would qualify as being top colour. See the cut stone here for what I mean by top colour: http://www.ruby-sapphire.com/tanzania-tanzanite-mines.htm.

Lots of less saturated off colour stuff which isn't unusual since it's everyone's second choice and it stays in inventory for longer.

Also, this whole "flooding the market" is nonsense... I've been following tanzy prices online for a while. There's very few of the online retailers who have top colour tanzanite on their sites in any quantity at all. Africa Gems, Swala and ParaibaInternational are the only ones I've come across and even then it numbers in the tens. Go check out GemSelect or Multicolour and you'll see exactly what I mean. Almost all of their stuff is off-colour.

I'll also add, since we're on the subject of so-called "colour infusion" that I've also been looking for a matched pair of Tsavorites. Even more difficult. And even more expensive.


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 Post subject: Re: Treated Tanzanite ?
PostPosted: Thu Jan 31, 2013 11:19 am 
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I was hoping for a courteous professional response. Something along the lines of....

Tanzanite cannot be diffused because of xyz scientific principle, or
There is some Tanzanite colored synthetic spinel showing up, not unlike the Peridot colored synthetic spinel that came and went a few years ago.

Instead I am met with childish attacks and veiled references to someone in the industry that few on the transaction side pay attention to.

Please do not put words in my mouth, I wrote "large quantities" not "flooding the market".

I do however appreciate that neither of you have seen said treated Tanzanite on your recent trips. It helps. But when I get a heads up from a trusted friend and business associate who lives and works as a wholesale gem dealer in Thailand I'm going to do some research. The last time I got a heads up, and posted here, the info showed up on the front page of the GIA a few months later. While I don't think this is going to be a major deal, it's still nice to get a heads up.

I question while I even bother posting here. Next time I won't bother. A little civility could go a long way.

As for Tanzinite purchases, I usually deal with one of the site-holders. It's not that hard to find a matched pair of top quality at a reasonable price. And they are usually happy to cut to your specs.

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I'll also add, since we're on the subject of so-called "colour infusion" that I've also been looking for a matched pair of Tsavorites. Even more difficult. And even more expensive.


I'm not sure I understand your Tsavorite "colour infusion" reference. Can you explain?

360


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 Post subject: Re: Treated Tanzanite ?
PostPosted: Thu Jan 31, 2013 11:40 am 
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Hey 360, I have not read anything in the literature (GIA, Gem-A, SSEF, AGL, etc) indicating the treatment of tanz you describe which is why I asked where you heard it.
So, this is "word of mouth"?
Would it be possible for you to get a sample of the material? I would be interested in having it inspected by Christopher Smith, AGL.

I think you are overly sensitive concerning the responses. They are humorous and contained useful information. Lighten up a little.
Our forum has very high search engine ratings. If someone searches for "Tanzanite diffusion treatment" and ends up on one of my pages, I want it clearly understood that there is NO current evidence to support that.

We pride ourselves on providing accurate information.....it is often not sugar coated, but it will be accurate. :)


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 Post subject: Re: Treated Tanzanite ?
PostPosted: Thu Jan 31, 2013 11:58 am 
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Well 360,
I'm sorry if I offended you by giving a truthful answer. I guess you should stick to buying your Tanzanites from the sightholder as you then probably would not risk any undisclosed treatments.

After going through hundreds of stones last weekend I stick to my opinion. Not easy to find a matched pair in top color. Perhaps I'm too anal about color but that's the way I am. Cutting I do by myself so slight difference in measurements or shape is of no real concern to me. Maybe I can use you as a broker next time when needing a top color pair?

Also the wholesalers in BKK I know and trust have yet to see what you describe. Maybe your contact is deeper into the BKK gem trading world than mine are... What GIA article are you referring to? Maybe you can ask your Thai wholesaler to chime in here to clarify?

There is still no published scientific evidence regarding color infusion in Tanzanite. Until there is, I consider it to be nothing than unverified claims built upon faulty conclusions. My advice to people buying Tanzanite (or any other gemstone) is to use their common sense and stick to the old saying: "If it seems too cheap to be true, it probably is..."

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 Post subject: Re: Treated Tanzanite ?
PostPosted: Thu Jan 31, 2013 11:32 pm 
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I'm not sure where in my post you felt I wasn't being civil.

However, to answer your question:

The term "colour infusion" is wholly the invention of one individual who first claimed that tourmaline was being diffused with copper. Then, when it turned out his "diffusion" was in fact simple dying, the term "dyefusion" was invented as an apparent CYA way of not having to admit he was wrong. This has since morphed into "colour infusion". This same individual claims that it's being done to pretty much every stone that he buys on eBay, including aquamarine, tourmaline, tanzanite and tsavorites, hence my comment. The term "colour infusion" does not exist outside of this one individual's imagination, it's not a recognized term in any of the serious gemological literature nor is it recognized by the gemological community at large.

He's been caught red-handed misstating the origin of stones:

http://www.badgemology.com/rebel-rebel-91.83-ct-green-sapphire-saga.php

http://www.badgemology.com/siam-i-am.php

http://www.badgemology.com/china-dealer-alert.php

He appears to have delved into the realm of DIY gem treatments in what looks very much like an attempt to fabricate evidence:

http://www.badgemology.com/chef.php

And in response to this individual's claim of "colour infusion" being done to Tanzanite, this science packed article with x,y and z's was put up on the same site:

http://www.badgemology.com/einstein.php

As to "large quanitites" vs "flooding the market", history in the gem business shows that when a successful new treatment is discovered, those stones do indeed flood the market. BE pads, lead glass filled rubies, diffused Andesine... There was no sign of either large quanitites, nor a market flood of top colour tanzanites my last two very recent trips to BKK. There is no sign of those large quantities making their way to the online retailers. There were very few top colour stones available at all, as I noted above. Those that I did see were all in the 5ct and up range, which is also pretty much the norm for Tanzanite as the colour often doesn't hold in smaller sizes. One would think that if a "colour infusion" process has been developed, it would also be just as effective, if not more so on the smaller stones, yet there wasn't a single small one in the several hundred stones I looked at that had "top colour".

Perhaps you'll understand Conny's reaction to your use of "colour infusion" a bit better after having read the linked articles above.

I'll also add that I was involved in a discussion on LinkedIn with one of this person's students who seemed to think that introducing colour into surface reaching cracks and growth tubes wasn't the same thing as dyeing. Apparently, she must have never had an example of dyed green quartz as an emerald simulant in hand. That led me to think that maybe this person's online course material is splitting hairs with the definition of dyeing in order to allow him to insert the term "colour infused" to define what everyone else recognizes as dyeing. The poor woman involved with this discussion made a complete fool of herself on a list of several hundred gemologists. She paid good money for her courses and seems to have ended up with an education tainted by ego and I quite frankly felt sorry for her.

EDIT: Am I imagining things that the original post on this thread said "colour infused" but now reads "diffused", or did I misread?


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