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 Post subject: Kashmir-like' sapphires from Madagascar: Trade Alert!
PostPosted: Wed Mar 29, 2017 12:59 pm 
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Dr. Michael S. Krzemnicki, SSEF wrote:
Kashmir-like' sapphires from Madagascar
entering the gem trade in large sizes and quantities

By Dr. Michael S. Krzemnicki, SSEF
In recent weeks, the Swiss Gemmological Institute SSEF has analysed a significant number of sapphires from a new deposit at Bemainty, near the small town of Ambatondrazaka in Madagascar, which were submitted to us by several reliable independent sources. Bemainty/Ambatondrazaka is the site of a new gem-rush in Madagascar, which over the past few months has produced an impressive amount of sapphires, fancy coloured sapphires, and padparadschas of partly exceptional size and quality (Krzemnicki 2017 in SSEF Facette http://www.ssef.ch/research-publications/facette/ and upcoming Journal of Gemmology, Perkins 2016, Perkins & Pardieu 2016, Pardieu et al. 2017), and it appears to be a new gem source of greater importance than anything we have seen in recent years.
Image

This Trade Alert focuses on sapphires from this new source in Madagascar which have a 'Kashmir-like' visual appearance. They are characterised by a subtle and fine milkiness, which results in a velvety blue colour typical of top-quality Kashmir sapphires.

Unfortunately, many of these new sapphires are accompanied by gemmological reports describing them as being of Kashmir origin. Having recently tested a sizeable number of such 'Kashmir-like' sapphires submitted by clients, and ranging in weight from 5 to 50 cts, we have concluded that many of these gems of so-called Kashmir origin actually originated from the new deposit near Bemainty/Ambatondrazaka in Madagascar. Our findings are based on meticulous microscopic observations, and also on an array of sophisticated scientific methods, including Raman microspectrometry, UV-Vis absorption spectrosopy, X-ray fluorescence and GemTOF (laser ablation inductively coupled plasma time-of-flight mass spectrometry) for trace element concentration (see also http://www.gemtof.ch and Wang et al. 2016).

The arrival of large quantities of new sapphires of Kashmir-like appearance is challenging for the gem market and gemmological laboratories alike, especially as we know that some of these Madagascar sapphires are being purposely introduced into the gem market with fraudulent claims of historic Kashmir provenance.


How can these new sapphires be distinguished from Kashmir sapphires?

The new sapphires from Madagascar can, to a great extent, be distinguished from Kashmir sapphires by careful microscopic observation. In combination with advanced methods such as trace element detection (eg. GemTOF) and Raman microspectrometry, further evidence can be collected to be able to confirm their origin.

Under the microscope (or loupe), the new 'Kashmir-like' sapphires from Madagascar often show an exceptional clarity (apart from a general milkiness), very much in contrast to sapphires from Kashmir, which often contain tiny but frequent inclusions of different kinds (pargasite, tourmaline, feldspar, uraninite), especially in stones above 10 cts. The new material from Madagascar often shows dense and narrow growth zones, compared to much more blocky three-dimensional growth zones in Kashmir sapphires (Figure 2), but to date has never shown the iconic pargasite and tourmaline inclusions that are highly characteristic of Kashmir sapphires.


Image

Occasionally, the new sapphires from Madagascar show a marked chromium concentration, resulting in larger purplish zones with a diffuse outline within the sapphire. This zoning feature is greatly in contrast with those found in Kashmir sapphires. In fact, Kashmir sapphires may show very thin and well-defined growth layers enriched in chromium, and are only visible when exposed directly to a strong light source, as reddish visible fluorescent layers (see Figure 3). Kashmir sapphires do not, however, show diffuse purplish colour zones under normal light.

Image

The new 'Kashmir-like' sapphires from Madagascar may show fine dust lines and tracks and flakes (Figure 4), which are to some extent reminiscent of similar structures in Kashmir sapphires. However, we would like to remind readers that similar structures have also been described in 'Kashmir-like' sapphires from Sri Lanka and Andranondambo (SE-Madagascar). Therefore, these features are only of limited use to identify the origin of a sapphire.

Image

However, the most challenging feature is that these new sapphires from Madagascar often contain tiny prismatic zircon crystals, somewhat similar to those seen in Kashmir sapphires. The zircons in the Madagascar stones are rather metamict, very much in contrast to zircons in sapphires from Kashmir.

The UV-Vis absorption spectrum of the new 'Kashmir-like' sapphires from Madagascar is very similar to the ones of Kashmir sapphires. It is mainly characterised by absorption features in the UV range related to their milkiness, and a small peak at 450 nm due to a low concentration of ferric iron (Fe3+).

Finally, it is possible to further separate these new Madagascar sapphires from Kashmir sapphires on the basis of their trace element chemistry, readily analysed with the GemTOF instrument at SSEF. This highly sophisticated instrument allows us to quantify chemical elements and isotopes even at sub-trace levels (ppb).

What measures can be taken to protect the trade?

As a world leading gemmological laboratory, the Swiss Gemmological Institute SSEF has analysed in recent years several of the most prestigious gemstones offered in the trade, including several exceptional sapphires from Kashmir that have shown classical inclusion characteristics described in detail by Gübelin & Koivula (1986 and 2008), Hänni (1990), Schwieger (1990) and Krzemnicki (2013).

With the sudden arrival at SSEF of similar looking sapphires from Madagascar in the range of 5 to 50 cts in recent weeks, we immediately initiated research and have finally succeeded in establishing stringent criteria to identify this new material and to distinguish it from Kashmir sapphires, when characteristic features permit this. This work is based on decades of experience in origin determination, state-of-the-art analytical instrumentation, and an extensive reference collection that is constantly upgraded with gemstones from new deposits, such as the described new sapphires from Madagascar.

The arrival of these new sapphires from the gemstone rush at Bemainty/Ambatondrazaka has great potential and should be an asset to the gem trade, as long as the true origin of these gemstones is correctly disclosed throughout the supply chain. It only becomes challenging or a threat to the trade when these sapphires are wrongly labelled, for example as Kashmir sapphires, and sold as such within the trade and finally to the consumer.

With this alert, we want to inform the trade about this new gem source of 'Kashmir-like' sapphires in Madagascar and raise awareness of the challenge they pose to the trade, which may have considerable financial and reputational impact if they are not properly disclosed.

REFERENCES:

Hänni H.A. (1990) A contribution to the distinguishing characteristics of sapphires from Kashmir. Journal of Gemmology, vol. 22, No. 2, 67-75.

Gübelin E., Koivula J.I. (1986 and 2008) Photoatlas of inclusions in gemstones. ABC Verlag Zurich and Opinio Verlag Basel, Vol. 1 and 3.

Krzemnicki M.S. (2013) Kashmir sapphire. SSEF Facette, No. 20, 6-9. http://www.ssef.ch/fileadmin/Documents/ ... E21-Bd.pdf

Krzemnicki M.S. (2017) New Sapphires from Ambatondrazaka, Madagascar. SSEF Facette, No. 23, page 15. http://www.ssef.ch/fileadmin/Documents/ ... tte-23.pdf

Krzemnicki M.S. (2017) New Sapphires from Ambatondrazaka, Madagascar, Journal of Gemmology, Volume 36, No. 5, (in print)

Perkins R. (2016) Sapphire rush in the jungle east of Ambatondrazaka, Madagascar: an expedition report. roseyperkins.com/wp-content/uploads/2016/11/SapphireRushMadagascarOctober2016by-RoseyPerkins.pdf
Perkins R., Pardieu V. (2016) Gem News International: Sapphire rush near Ambatondrazaka, Madagascar. Gems & Gemology, 52(4), 429-430.

Pardieu V., Vertriest W., Weeramonkhonlert V., Raynaud V., Atikarnsakul U., Perkins R. (2017) Sapphires from the gem rush Bemainty area, Ambatondrazaka (Madagascar).
http://www.gia.edu/gia-news-research/sa ... madagascar
Schwieger R. (1990) Diagnostic features and heat treatment of Kashmir sapphires. Gems & Gemology, Vol. 26, No. 4, 267-280.



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 Post subject: what a surprise! labs admit defeat ;)
PostPosted: Wed Mar 29, 2017 1:55 pm 
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What a surprise, Labs admit defeat.

http://myemail.constantcontact.com/SSEF ... feIQXkiGYQ


and there is still a lot to learn, i promise!


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 Post subject: Re: what a surprise! labs admit defeat ;)
PostPosted: Wed Mar 29, 2017 4:07 pm 
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Why do you say "labs admit defeat"? My interpretation of this article is that SSEF is aware that some Madagascar stones have been mislabeled as Kashmir lately (possibly under pressure from a market that has been pining for Kashmirs for over 100 years now,) and that they have established a set of gemological criteria to distinguish between the two. Sounds like par for the course to me? Either way I am :mrgreen: to see a new supply of quality sapphire on the market, and there are rubies too!

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 Post subject: Re: what a surprise! labs admit defeat ;)
PostPosted: Wed Mar 29, 2017 4:46 pm 
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they do not only have been labeled as kashmir by major labs but already sold as such stones.
so, there is a huge amount of people who recently bought kashmirs because labs failed in what they do.
of course is ssef not saying we totally "watch you language" it up. and they didnt only "watch your language" up kashmirs but other origins too. for ages. ssef is not alone.
book knowledge vs battlefront.
but i told all this here already.

funny also that ssef, you are the best example, is on screen now as the researchers who found out big stuff, instead of publishing their burma story, which was kept up for decades and which made that people make billions.
this business chapter is closed now but the next is already open. we talk again about techniques in 4 years. ;)

a lots of pads popping up these days by the way! big big pads!

you learned from ssef and to me its a clear admit of defeat. a bit sneaky though.
traders were laughing already.

greetz from basel


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 Post subject: Re: what a surprise! labs admit defeat ;)
PostPosted: Wed Mar 29, 2017 6:46 pm 
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 Post subject: Re: what a surprise! labs admit defeat ;)
PostPosted: Fri Mar 31, 2017 2:28 pm 
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My 2¢.
Gemology, like science in general, is a process of ongoing research and discovery.
I believe that is the definition of "the scientific process".

One does not know what they don't know.

Examples:
-The expanding earth theory replaced by plate tectonics.
-The canals on Mars which proved to be trails of blowing dust.
-Einstein's static universe replaced by the Big Bang theory.
-Tibetan and Congolese red andesine originally displayed as a natural wonder at the Smithsonian which turned out to be treated yellow material from Mongolia.
-High quality sapphires displaying properties of Kashmir stones turned out to be from Madagascar, separated by sophisticated instrumentation.

None of these examples are "defeat" they are great successes....which will lead to more insights in the future.


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 Post subject: Re: what a surprise! labs admit defeat ;)
PostPosted: Mon Apr 03, 2017 3:06 am 
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Barbra Voltaire wrote:
My 2¢.
Gemology, like science in general, is a process of ongoing research and discovery.
I believe that is the definition of "the scientific process".

One does not know what they don't know.

Examples:
-The expanding earth theory replaced by plate tectonics.
-The canals on Mars which proved to be trails of blowing dust.
-Einstein's static universe replaced by the Big Bang theory.
-Tibetan and Congolese red andesine originally displayed as a natural wonder at the Smithsonian which turned out to be treated yellow material from Mongolia.
-High quality sapphires displaying properties of Kashmir stones turned out to be from Madagascar, separated by sophisticated instrumentation.

None of these examples are "defeat" they are great successes....which will lead to more insights in the future.


we should really add a "like" button somewhere.... :wink: :wink: :wink:

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 Post subject: Re: Kashmir-like' sapphires from Madagascar: Trade Alert!
PostPosted: Mon Apr 10, 2017 3:45 pm 
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It seems that not all living beings in Madagascar appreciate this pseudo-Kashmir sapphire rush.

http://edition.cnn.com/2017/04/06/afric ... adagascar/


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 Post subject: Re: Kashmir-like' sapphires from Madagascar: Trade Alert!
PostPosted: Mon Apr 10, 2017 8:12 pm 
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Gem mining generally is a very ugly business.


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 Post subject: Re: what a surprise! labs admit defeat ;)
PostPosted: Thu Apr 13, 2017 2:04 pm 
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Barbra Voltaire wrote:
My 2¢.
Gemology, like science in general, is a process of ongoing research and discovery.
I believe that is the definition of "the scientific process".

One does not know what they don't know.

Examples:
-The expanding earth theory replaced by plate tectonics.
-The canals on Mars which proved to be trails of blowing dust.
-Einstein's static universe replaced by the Big Bang theory.
-Tibetan and Congolese red andesine originally displayed as a natural wonder at the Smithsonian which turned out to be treated yellow material from Mongolia.
-High quality sapphires displaying properties of Kashmir stones turned out to be from Madagascar, separated by sophisticated instrumentation.


None of these examples are "defeat" they are great successes....which will lead to more insights in the future.


Spot on Barbra. It's too easy to be wise after the event.


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