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 Post subject: Re: Intense pink/Magenta Katlang topaz specimen on eBay
PostPosted: Fri May 02, 2014 10:47 am 
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Wali at Five Lions has had a couple of these deep pinks in years past. I believe the last big one was
About 12 carats with nice termination. It was clearly facet grade and found a buyer at $10k.

Tom Kidwell


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 Post subject: Re: Intense pink/Magenta Katlang topaz specimen on eBay
PostPosted: Tue Apr 07, 2015 5:44 am 
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my friend told that katlang topaz are often treated on matrix,i do katlang topaz mining,they are by no way treated of any kind ,even the people not know such things,most of the miners are illiterate ,why the people makes such foolish comments ,two area in katlang produces pink topaz,ghundo ,and shamozai dara few kilometers from ghundo mine,but dara produces slight pink topaz ghundo hot pink,please donot make stufid comments without knowing anything,see my facebook page,mehboob alam mardan khel, thanks


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 Post subject: Re: Intense pink/Magenta Katlang topaz specimen on eBay
PostPosted: Tue Apr 07, 2015 2:31 pm 
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The treatment on matrix is gamma irradiation to turn the stones a deep red-orange to rival the finest Brazilian imperial topaz (a color which unfortunately fades in sunlight). This is of course not performed out in Katlang but presumably in Lahore at the food irradiation facility where so many kunzite, tourmalines and common topazes are also treated. I've had this treatment performed on some samples of pale Katlang topaz myself, turning pale stones a rich orange.
I got into Katlang topaz by purchasing a very large parcel of orange-red Katlang stones online, allegedly directly from miners via an intermediate. As I understand it this deep red-orange color is never natural, so these stones must have been irradiated. They faded very quickly to very pale orange or champagne, it only took about 3 days for the most stubborn stones.
Side note: I purchased a specimen of paler orange/tangerine Katlang topaz on matrix. It did not fade in three weeks of direct sunlight.
The treatment to turn orangy or champagne Katlang topaz pink is heat, which would be hard to perform on a calcite matrix. It's a very mild treatment, around 300-400 degrees c, milder than what's needed to turn Brazilian imperial topaz pink (~500 seems to do it for them), but not mild enough to not destroy the calcite. The resulting pink color is impressive, often more saturated than the champagne or orange color was. It also really performs in some light, and seemed to improve a bit over time after the treatment (likely just a result of different light conditions).
I ended up heat treating most of the irradiated orange Katlang stones I had purchased, and the result was a very pleasing purplish-pink color. This does beg the question: why did they irradiate the stones to turn them unstable red-orange instead of heating them to a very desirable and totally stable light purple-pink? I feel a bit bad for getting upset with the guy who sold them to me--even though I found out he knew about the irradiation and told me they were untreated,the price in retrospect was actually good for pink topaz.

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 Post subject: Re: Intense pink/Magenta Katlang topaz specimen on eBay
PostPosted: Wed Sep 16, 2015 1:35 pm 
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dear ,i belong to district ,mardan katlang area. i do mining of katlang topaz.you can say anything about price,but u cant say anything,about treatment,without due knowledge.katlang topaz is produced ,in pink ,imperial.golden some very deep and some light colors.the people of this area are completely unaware of any treatment.i have been mining for previous two years.i challenge any person can come here and experience by their own eyes,what is produced here is fake or real.


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 Post subject: Re: Intense pink/Magenta Katlang topaz specimen on eBay
PostPosted: Wed Sep 16, 2015 2:48 pm 
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I really wish I could. It's really interesting to me that early reports on Katlang do not mention intense orange stones at all, but they are pretty common on the market now (relatively speaking). There was also the relatively recent announcements of a new treatment producing this color in Katlang topaz, including a full G&G article (Farooq Hashmi was involved with that). I have little doubt that at least some of the orange Katlang stones on the market now have been irradiated--it's easy, it's cheap, it reliably produces an incredible stone from an inexpensive starting material and leaves no marks. The same has been done to Brazilian topaz, though I don't know how common it is nowadays.
But of course, that some samples are irradiated doesn't mean that all are. If you've seen them come out of the ground that color I'll take your word for it. I recently got a matrix specimen which also had quartz crystals mixed in the calcite which I noted did not show the characteristic black appearance of irradiated quartz, another good piece of evidence. I've also been rather pleased with a few samples which kept most or all of their orange color when exposed to sunlight (none of the intense orange-reds, though).
I feel confident the particular large parcel that I bought was irradiated because I found an older page on the rough seller's website that disclosed radiation on similar Katlang stones. I don't know, though, whether he knew that directly or if he was just copying what Farooq had said on his page.

As a side-note, I recently got a nice big parcel of Katlang crystals in varying shades of orange and brown. It is very neat to see an almost full spectrum between pure red-orange and normal topaz brown, with some truly stunning orange-red-brown stones in between. Most are bicolors as well. Hard not to love them, irradiated or not.

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 Post subject: Re: Intense pink/Magenta Katlang topaz specimen on eBay
PostPosted: Thu Oct 15, 2015 11:25 am 
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dear ,mining is starting soon after a long time break,u will see soon some fine pieces pink ,yellow golden,yellow like honey,reddish yellow,hot pink,katlang is famous for pink topaz,but all said colors are aslo find,but pink is not usually very hot pink,but many pieces of hot pink has been found,Ghundo hill is famous and first producer of pink topaz,Shamozo has some time produced pink but not very pink like Ghundo hill,Shamozo area is two km away from Ghundo hill,i have seen heated topaz of gilgith ,which fade its color in a day in direct sunlight,but i have never seen in katlang topaz..i donot mean that nobody will have tried in pakistan but i guarantee not the people of this area,when i find some fine pink pieces ,i will try to exhibit it in a gem show in europe,and challenge top class gemologists to test in any laboratory they want,i want to let the people know that natural pink topaz produced here,


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 Post subject: Re: Intense pink/Magenta Katlang topaz specimen on eBay
PostPosted: Thu Oct 15, 2015 12:05 pm 
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I recently tested a few stones from my latest parcel. Unlike most katlang stones I have tested, these faded from rich orange and orange-red to pastels in a few hours of sunlight (other samples usually take 3 days to reach final color). The resulting colors were light pink, light orange, pale green (could be pale blue plus light iron staining) and colorless. So stability can definitely be similar to or less than irradiated (not heated, heat can't induce brown in topaz) skardu or gilgit topaz. .Natural stones can be unstable too, of course.

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 Post subject: Re: Intense pink/Magenta Katlang topaz specimen on eBay
PostPosted: Thu Dec 17, 2015 10:41 am 
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I have this 6 ct pink topaz from Katlang mine. Unheated untreated. Can anyone please tell me the fair market value for this stone.


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