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What about heliodor from Tajikistan?
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lluis




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PostPosted: Aug 04, 2011 14:06    Post subject: Re: What about heliodor from Tajikistan?  

Dear Mr. John White, list

Well, being curious as the proverbial cat, I searched the net for things to add more light to the fact

and I found an article in jewellery that is quite interesting.

https://www.jckonline.com/article/290139-Yellow_Beryl.php
(link normalized by FMF)

For those that would skip all reading, the points

- a short burst produce color in beryl. Quicker than coloring blue topaz
- discovery was when treating topaz
- different mines yield different colors, due to impurities in the material.
- could be had lemon yellow and the darker one

Well, all that matches what Peter has said, and what Mr. John White observes.

Not to be forgot that, as a russian expert says, in Tajikistan names of mines are in the language of the country, that is farsi related. Not in Russian. And for more precission, he said that the name should be Zolotaya Voda, in Russian...

With best wishes

Lluís
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bob kerr




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PostPosted: Nov 13, 2011 09:50    Post subject: Re: What about heliodor from Tajikistan?  

i'm new to this forum being referred to it by john white. i would like to add some additional "evidence" for consideration - that being a specimen of heliodor - alledged from tajikistan - that is on matrix in association with white/milky quartz (photo attached). being somewhat familiar with radiation, i think it would be a difficult challenge to irradiate this specimen with gammas such that only the beryl is hit and the quartz remains white. most radiation facilities, that treat food for example, provide bulk gamma treatment (maybe from Co60 source).

so could a "columnated" gamma beam be used? i don't think this is likely - it's a challenging engineering issue. could electron beams be used? possibly - but given the large amount of material out there, this seems unlikely also.

another question - is the color in ALL "natural" heliodor caused by natural radiation? if so then i would expect the white quartz in the photo to be darkened. i think, though, that the coloration can be caused by a certain iron valence without radiation - anyone know for sure?

so, to me this issue is still open with valid arguments on both sides.

bob



heliodor quartz small.JPG
 Description:
heliodor with quartz
tajikistan
6.5cm tall
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heliodor quartz small.JPG


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bob kerr




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PostPosted: Nov 13, 2011 10:06    Post subject: Re: hello!What about heliodor from Tajikistan?  

paul - for completeness of this thread, i include the flying provided by that german dealer (ed link of gemworld) to which you refer in your post.

he shows brownish/orange beryl that is caused by irradiation and this coloration should give away any irradiated material - but not so fast. one could simply over expose the beryl to "burn it" to the brownish/orangish tinge. a small dose could possibly provide the purer yellow coloration. so this does not, as the flyer says, put this to rest.

this is still a caveat emptor sitiation - but to me if you resell these items and state as john white suggests: "locality and color are questioned by many" and maybe even refer them to this and other threads then i don't think this is being unethical at all.

bob


Paul Bordovsky wrote:
The Extra Lapis article is quite instructive on this matter. If I remember correctly, the author
inadvertantly contributed the location, when viewing specimens at a dealer who didn't
have any locality data. But those details are in the article.

Back in 1999 or 2000 I was looking in Tucson for these heliodor specimens. None of the
dealers in any of the hotel shows had any of them. However, there was a German guy in
the tent city across Interstate 10, who had many of them. The word was already out as to whether these were genuine. This guy had an article posted in his area denying that they
were irradiated. He had pictures purportedly taken by Jeff Scovil showing specimens
before and after irradiation, "proving" that these heliodors couldn't be due to this process.

The next day I was browsing in a Paki/Afghani dealer's hotel room. I asked him if he had any of the heliodors. He said that those were fakes. He said that there was a German guy
that was buying up goshenite specimens from the Pakis and Afghanis very cheaply. That
this German guy had some machine that cost 50,000 or 100,000 USD. ( I can't remember anymore which anymore). That he was bragging that he was making a lot of money selling these specimens as authentic.

The dealer said the process was "sintering". I think that this is some sort of surface
treatment, but those of you who know more of this can correct me.

Anyway, I did buy a modest specimen from the German, assuming it was fake, and
the subsequent discussion with the Afghani dealer confirmed it for me.

Paul



File0005.jpg
 Description:
heliodor
tajikistan
 Viewed:  18945 Time(s)

File0005.jpg



File0006.jpg
 Description:
 Viewed:  18939 Time(s)

File0006.jpg


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lluis




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PostPosted: Nov 13, 2011 11:51    Post subject: Re: What about heliodor from Tajikistan?  

Hi, Bob

Well, if you take the time to read the link, it states that a *short* burst of gamma or electron induces the heliodor color.

Short mens that topaz is not changed in color. Not quartz.

Of course, if you burnt the material, you could get a morion quartz.
And colour of beryl would go as deep as it could, but that not means that will get black also.

So, well, I would be very pleased to see anyone that shows a in situ pocket with heliodor beryls.

If you are not convinced by Paul explanation, by the fact that only one dealer in Tucson is selling such, and the link that explains how, when and so, well, I only could say that I have not a photo of people irradiating the pieces, but mine is in the tray of "faked minerals"

With best wishes

Lluís
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weaver




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PostPosted: Nov 13, 2011 12:26    Post subject: Re: What about heliodor from Tajikistan?  

In the mineral world, is it the same as everywhere else, in regard to mystique? I noticed with some areas of mystique, if you apply a foreign name (See following example) people get excited over virtually nothing:

E.g. - It seems that if you have a common item, say, a bamboo flute that you buy for $3.00 from a street vendor in China. Then you bring it back to the USA, and tell people it's a rare TIBETAN BUDDHIST RITUAL FLUTE, the price increases exponentially.

~

When I see rocks from Tajikistan, I wonder if the exotic location attracts the less inclined based on perceived value? I bet rocks samples that have the word 'Himalayan' in their title sell better than rocks from plain ol' Alabama.

"RARE TIBETAN QUARTZ!!! So rare, you can only find it in ONE place!!!"

I understand the process of heating/radiating/electro/chemically treating stones to attract curiosity seekers. In this case, I [suspect/wonder] if the _name_ is also valuable:

HELIODOR from TAJIKISTAN!
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PostPosted: Nov 13, 2011 13:49    Post subject: Re: What about heliodor from Tajikistan?  

What about green beryl from Finland?
THE MINE EXIST, it was discovered in 1984 building a road and a first shard of topaz cleavage was found. It is still a mining claim, located in Kännätsalo, on an island in Kivijärvi, NE Luumäki, Karelia, Finland.

Is it not very strange that no one in Tadzhikistan or Russia or anyone else have ever published a serious report of a "find of extraordinary "heliodores" in "Tadzhikistan".
I think the US customs must have a huge import list every year of heliodors from Tadzhikistan! I wonder how long this will go on????

The first ones appeared in Tucson 1992 and were said to be from Pakistan.
The guy exhibited at the Executive Inn show second floor and after half an hour gave up trying to convince me these were natural from Pakistan. In Denver 1992 they were then said to be from Tadzhikistan!
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bob kerr




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PostPosted: Nov 13, 2011 20:12    Post subject: Re: What about heliodor from Tajikistan?  

lluis - a few thoughts on your comments:

1 - i did read the link that states "short burst" colors beryl. it does not state that the short burst does not color topaz (blue). as a matter of fact the short burst MUST color the topaz to some extent. the key issue is that is there an amount of gamma exposure that will color beryl but not color topaz - or, in my specimen, is there an amount of gamma exposure that will color beryl but not the quartz. i think this is not likely at all - the quartz MUST darken to some extent (ESPECIALLY given it's milky nature which is indicative of significant impurities) and there's no trace of darkening at all. there are also numerous other heliodor/quartz pieces out there - none that i've seen show any quartz darkening.

but i agree that there MAY be a short enough gamma burst (the radiation field strength MUST be specified though - one second exposure at a field strength of 10mR/second is the same as 1 hour at .003mR/sec) that will color beryl but not quartz - i just don't think this is likely at all.

2 - for anyone to make a statement that "there is only one dealer in tucson selling them" is to state an impossibility - one person - or many for that matter - cannot possibly see all the booths, motel rooms or tents at the show. and anyway, i know of three dealers who handle lots of them - one is ed link at gemworld california, another is al-rehman gems from pakistan and there's another that was located in the holiday inn holidome that i did not get the name of but did get photos of specimens in his room.

3 - your "link that explains how, when and so" does not discuss at all how it could be done with quartz or clevelandite in association with the beryl and not darken the quartz.

4 - if the locality specified for these specimens if shown to be wrong, that would say nothing about the authenticity of the pieces. there are LOTS of examples of people all over the world (USA included) giving false locality/mine names in order to hide the locality from claim jumpers.

so, i remain confused and have not yet seen any definitive evidence either way. i guess it all depends on your point of view - are these guilty until proven innocent or innocent until proven guilty?

bob


lluis wrote:
Hi, Bob

Well, if you take the time to read the link, it states that a *short* burst of gamma or electron induces the heliodor color.

Short mens that topaz is not changed in color. Not quartz.

Of course, if you burnt the material, you could get a morion quartz.
And colour of beryl would go as deep as it could, but that not means that will get black also.

So, well, I would be very pleased to see anyone that shows a in situ pocket with heliodor beryls.

If you are not convinced by Paul explanation, by the fact that only one dealer in Tucson is selling such, and the link that explains how, when and so, well, I only could say that I have not a photo of people irradiating the pieces, but mine is in the tray of "faked minerals"

With best wishes

Lluís
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PostPosted: Nov 13, 2011 23:49    Post subject: Re: What about heliodor from Tajikistan?  

We seem to have two different topics going here, mixed up at the same time:

1) Are they natural or irradiated or otherwise treated? (And I have no opinion on this as it's outside my expertise.)

2) Are they from Tazhikistan? (Probably not. ... and that makes them worthless for most serious mineral collectors, who generally insist on accurate locality information. Nevertheless they would still have some value as cutting rough.)

Cheers,
Alfredo
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PostPosted: Nov 14, 2011 05:49    Post subject: Re: What about heliodor from Tajikistan?  

Perhaps my position on this cannot be supported but I do not consider these heliodors worthless in spite of the fact that their source appears highly questionable and their color is also under suspicion. I have bought and sold quite a few to collectors who were happy to have them even after my explaining the questions that exist surrounding their origin. It may be nothing more than these collectors wanting a sample of a material that is surrounded by mystery. I have a very fine example in my single crystal collection and, sorry Alfredo, I do not consider them "worthless except for cutting."
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PostPosted: Nov 14, 2011 07:59    Post subject: Re: What about heliodor from Tajikistan?  

if "serious collectors" insist on accurate locality info, then these collectors will probably need to get rid of many chinese specimens in their collection!

and many mines change names with different owners or claim holders - does "accurate" mean that the locality name must reflect the name of the mine at the time it was collected?

does the "locality" minas gerais, brazil have any meaning at all.

i'll stop there - MANY collectors insist on accurate locality info - weather that makes them SERIOUS collectors is in the eye of the beholder.

bob

alfredo wrote:
We seem to have two different topics going here, mixed up at the same time:

1) Are they natural or irradiated or otherwise treated? (And I have no opinion on this as it's outside my expertise.)

2) Are they from Tazhikistan? (Probably not. ... and that makes them worthless for most serious mineral collectors, who generally insist on accurate locality information. Nevertheless they would still have some value as cutting rough.)

Cheers,
Alfredo
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PostPosted: Nov 14, 2011 08:16    Post subject: Re: What about heliodor from Tajikistan?  

The discussion is coming out the focus. The discussion is not if the vendor have the right to sell yellow beryls (irradiated or not) or if he should supply accurate details of the locality, but about if he (they) is (are) telling lies about the real locality and the (potential) treatment of the Beryls.

I believe the vendor should prove the reality of the locality he gives, not the buyers or watchers, and for the moment seems that vendor or vendors of this kind of stuff never gave any detail (or them were confuse or contradictory as mentioned before in this thread) about the "Tajikistan" locality.

After all this years it seems reasonable have more details about it, not just "Tajikistan".
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PostPosted: Nov 14, 2011 08:33    Post subject: Re: What about heliodor from Tajikistan?  

Not quite sure what Jordi's point is. I think we all agree that it is wrong for a dealer to sell minerals as naturally-colored and/or from a specific locality when he or she knows that information is false. But when the mineral appears on the market, I see no reason why it should not be sold as "shrouded in mystery." This, in fact, can add a lot of appeal to the pieces, even if many consider it improper. What are we to do with all of these yellow beryls, throw them away? They are nice crystals, at least the ones like that in my collection, less so the flat ones of an ugly color that occur with what appears to be zapped muscovite.


beryl Tajikistan.JPG
 Description:
Heliodor in albite matrix - "Tajikistan"
not in my collection, but one that I have sold.
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beryl Tajikistan.JPG



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PostPosted: Nov 14, 2011 08:46    Post subject: Re: What about heliodor from Tajikistan?  

John S. White wrote:

But when the mineral appears on the market, I see no reason why it should not be sold as "shrouded in mystery".


I agree Master, but "when the mineral appears on the market" not after 20 years ;-)
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PostPosted: Nov 14, 2011 10:21    Post subject: Re: What about heliodor from Tajikistan?  

Quote:

I agree Master, but "when the mineral appears on the market" not after 20 years ;-)


Jordi - you have a point to some extent, but in that area of the world i think a good argument can be made that what we consider in the west as normal or typical doesn't apply there.

and in China - when those excellent mimitites first came out there was a raft of different localities given but after a number of years the real locality (i think!) was specified. if you would've not bought any when they were numerous because the locality was not clear, you would've had to get one after they went through many middle men and with a comensurate high price.

i guess for these heliodors, we'll only know for sure if the real locality is given and independently verified or if the perpetrator(s) of the coloring comes clean. i still though would like to know how he was able to color beryl yellow without darkening associated quartz.

thanks,
bob
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PostPosted: Nov 14, 2011 10:39    Post subject: Re: What about heliodor from Tajikistan?  

I completely agree with Alfredo on this one. There are two separate issues here - 1) are these natural or irradiated? and, 2) are they from Tajikistan?

Given the inability of anyone, after all the time these things have been on the market to offer any details what so ever about the supposed locality (including every Russian mineralogist and dealer I've spoken with) strongly suggests that the locality is fictitious.

I will guarantee that at least some of the material I've seen on the market labeled as coming from Tajikistan is fake. I have seen on numerous occasions specimens identical in habit and association to those from other well-known aquamarine locations including Ping Wu, China and Nager, Pakistan. There really appears to be no single or consistent set of habits and associations for this material, which suggests to me that someone is simply acquiring beryl specimens from any of a number of localities, treating them, and selling them on attributed to our "mystery" locality.

While I am not a expert on the topic of radiation-induced color change in minerals, it is my understanding that the darkening effect in quartz is related to the amount of Al that has substituted for Si in the crystal structure. If one has low-Al quartz, is the dose threshold necessary to induce a color change higher than would be needed to turn an associated aquamarine to helidor? If so, then one could expect to produce yellow beryl on white quartz. Over twenty years I'm sure the technicians doing this have had time to develop their technique.

Cheers,
Jesse
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PostPosted: Nov 14, 2011 11:06    Post subject: Re: What about heliodor from Tajikistan?  

I have to disagree with Jesse about the habit. The fine quality loose crystals usually free of matrix have a distinct habit that is virtually consistent throughout the lot. There are other, previously mentioned, flattened ones of an ugly color occurring with muscovite that could be from anywhere, China or Pakistan. I have not seen the habit I am referring to in abundance from Pakistan. Even if treated and even if not from Tajikistan (as seems to be the case) I suspect that they are from a totally different pegmatite than those that have produced most of the aquas from Pakistan. Their habit is uniform and distinctive.

As for Jordi's point, if the truth has not surfaced even after 20 years, then my guess is that it never will. To some extent his point is moot anyway, because one rarely sees them being sold today.

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PostPosted: Nov 14, 2011 11:21    Post subject: Re: What about heliodor from Tajikistan?  

John,
While not definitive, the habit of all those fine loose crystals free of matrix is identical to what comes from the Shigar Valley in Northern Pakistan, which just happens to have been one of the most prolific source of aquamarine over the past 20 years. Because if it's association with blocky albite rather than cleavelandite (typical of the Shigar pegmatites), I would hazard a guess that this is where the matrix specimen you posted a photo of is from, as well.

At any rate, I think it wise for people to be skeptical when faced with things like this. As we all know (or should know), where money flows fraud will follow.

Jesse
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PostPosted: Nov 14, 2011 11:33    Post subject: Re: What about heliodor from Tajikistan?  

jesse - you are correct about the fact that Al is the impurity in quartz that causes the "smokey" response to gamma radiation. almost without exception these specimens have mica, lepidolite, feldspar and a whole raft of Al bearing minerals in association. i'm makeing the assumption that the quartz in association with these is milky due to impurities that contain Al - i think this is a very good assumption and as such should be very susceptible to darkening upon gamma irradiation. i will stand corrected if input from a more knowledgeable shows up.

to me the issue is; can a certain gamma exposure color the beryl and not darken at all the associated quartz - i doubt this can be done - but again, i'll stand corrected if input is received from a more knowledgeable souce shows up - which is the main reason i started this discussion.

bob
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PostPosted: Nov 14, 2011 13:33    Post subject: Re: What about heliodor from Tajikistan?  

Bob, the Al in quartz that leads to smoky colour on irradiation is present substituting for Si in the quartz lattice itself, invisibly, not as inclusions of Al-bearing minerals. The "milkyness" of quartz crystals is caused by myriad inclusions of liquid and/or gas (microscopic "bubbles"), not solid Al-bearing inclusions.

And, as David von Bargen has pointed out in the parallel Mindat thread on this topic, you only need to heat smoky quartz to get rid of the smoky color after irradiation. So it seems the support for natural origin is getting still weaker.

Alfredo
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PostPosted: Nov 14, 2011 14:21    Post subject: Re: What about heliodor from Tajikistan?  

even though the Al needs to be in the quartz lattice, it is clear that a good bit of Al was around during the formation of these specimens so i still think it's a good assumption that there would be a good bit of Al in the milky quartz lattice.

and for heating smokey to clear it up - wouldn't this also impact the heliodor? there's lots of demonstrations of treated aquas and heliodors going to goeshenite with heating. the question is one of the right temperture and duration to clear the quartz and not clear the heliodor.

a friend of mine is gonna try an experiment with this - heat both smokey and heliodor and attempt to see what happens. it may not be the exact case but should be instrutive.

bob

alfredo wrote:
Bob, the Al in quartz that leads to smoky colour on irradiation is present substituting for Si in the quartz lattice itself, invisibly, not as inclusions of Al-bearing minerals. The "milkyness" of quartz crystals is caused by myriad inclusions of liquid and/or gas (microscopic "bubbles"), not solid Al-bearing inclusions.

And, as David von Bargen has pointed out in the parallel Mindat thread on this topic, you only need to heat smoky quartz to get rid of the smoky color after irradiation. So it seems the support for natural origin is getting still weaker.

Alfredo
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