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 Post subject: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Wed Mar 02, 2011 11:05 am 
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Hello,

Recently I have had some personal communications that many, if not all, yellowish green (lemon) and green (prasiolite) quartz coming from Brazil is actually treated, not only by heating but also by previous irradiation.

I can't find anything about this treatment in gemological literature, for example, in the last CIBJO Blue Book, the irradiation is only mentioned as possible treatment for smoky quartz, and only heating for citrine and prasiolite:
Annex A, page 53-54.
[pdfview]http://download.cibjo.org/Gemstone_Book_2010.pdf[/pdfview]

But I have found two articles of the same Brazilian team of authors talking about the irradiation as a common treatment for these colors of quartz, dated on 2007 and 2009:
[pdfview]http://www.ipen.br/biblioteca/2007/inac/11962.pdf[/pdfview]
[pdfview]http://pintassilgo2.ipen.br/biblioteca/2009/inac/15185.pdf[/pdfview]

Does somebody have more information on this?
Is it a common treatment applied to nearly all lemon and prasiolite we can see in the market?
Some more publications or field/market data?

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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Thu Mar 03, 2011 5:33 am 
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That 2009 paper is an interesting read! Didn't know that...


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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Thu Mar 03, 2011 9:10 am 
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Glad I still have one of those mexican "madeira-citrines" from the early eighties... :) It is in need of a recut though. One of my first faceted stones, cut on a modified pottery wheel :shock:

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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Thu Mar 03, 2011 7:58 pm 
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Just for fun, some lemon citrine from Tucson 2005, at the Electric Park, sold by a family of Brazilian pegmatite miners, dad, mom, son (in the photo) and daughter. The dad told me of a Brazilian saying to the effect that God created the entire rest of the world in six days - but on the seventh day he created miners.

Attachment:
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Tucs-lemoncit122sm.jpg [ 171.26 KiB | Viewed 4572 times ]


Attachment:
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TucsLemoncit120sm.jpg [ 172.89 KiB | Viewed 4572 times ]




Cheers all,
Hans Durstling
in Snowmageddon Moncton Canada

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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Thu Mar 03, 2011 10:35 pm 
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:smt001 Citrine on tap :smt118
LOL, Snowmageddon :lol:

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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Fri Mar 04, 2011 8:09 am 
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http://www.mindat.org/mesg-15-38542.html

http://www.quartzpage.de/prasiolite.html

http://www.quartzpage.de/citrine.html

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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Thu Mar 10, 2011 8:49 am 
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Thanks for all answers!

On the same time to publish this topic, I also asked the same question in our Spanish gemology forum (http://www.ige-gemologia.es/foro), and I just have received very interesting information from Brasilian gemologist working in the firm especialized in gamma irradiation of gems.

I copy here his answers and also the documents he sent to me, after his authorization. It's very interesting reading, note that other materials: morganite, green beryl, "hiddenite" and fluorite commonly irradiated are not mentioned in the CIBJO Blue book as possibly irradiated!

"My name is Mauricio Favacho , I am a MSc. geologist and gemologist in chief of GEMSTONE DEPTO OF CBE-EMBRARAD COMPANY, a brasilian radiation facility located in São Paulo city of Brazil , our company have been treating colorless quartz for lemon and prasiolite green color during 15 years among others color gemstones sucessfuly. So, the answer is the prasiolite and lemon quartz that are spread all over the world have been treated by us in Brazil by cobalt-60 gamma radiation, the montezuma mine do not produce a quilo of prasiolite nowaday, so such occurence is not a reference of such material anymore. I would like to point ou theres a secret concercing about the gemstone enhancement performed by our company, including the atmosferic condition of such enhancement, temperatura and so on . Send me your personal email that I will send to you more informations about it if necessary. Thanks

http://www.cbesa.com.br mfavacho@cbesa.com.br"


Download it here: http://www.ige-gemologia.es/imagenes/fo ... brasil.pdf
[pdfview]http://www.ige-gemologia.es/imagenes/foro_ige/gamma_processing_gems_brasil.pdf[/pdfview]


HIGH TECHNOLOGY ON GAMMA PROCESSING OF GEMSTONES
SÃO PAULO-BRAZIL

“25 YEARS ENHANCING GEMSTONE WITH QUALITY”

OUR PRODUCTS

EXPERTISE ON COLOR ENHANCEMENT FROM THE COLORLESS TO COLORED ONES OF NATURAL GEMSTONES SUCH AS :

COLORLESS QUARTZ TO GREEN GOLD (ORO VERDE QUARTZ).
COLORLESS QUARTZ TO LEMON QUARTZ.
COLORLESS QUARTZ TO SMOKY / MORION QUARTZ.
COLORLESS QUARTZ TO BLACK QUARTZ (SIMILAR TO ONIX GEMSTONE).
COLORLESS QUARTZ TO PRASIOLITE (LIME QUARTZ, MINT AMETHYST, GREEN AMETHYST) .
COLORLESS QUARTZ TO COGNAC CITRINE, YELLOW AND ORANGE CITRINES.
COLORLESS QUARTZ TO ROSE D’ FRANCE QUARTZ.
SLIGHTLY GREEN FLUORITE TO DEEP BLUE AND DEEP GREEN FLUORITE.
SLIGHTLY ROSE SPODUMENE TO DEEP ROSE KUNZITES AND GREEN HIDDENITES.
SLIGHTLY RED TOUMALINES TO DEEP RED AND ROSE TOURMALINES FROM DIFFERENT LOCALITIES SUCH AS NIGERIA, BRAZIL, SOUTH AFRICA AND APHEGANISTAN .
COLORLESS BERYLS TO ROSE MORGANITE , YELLOW TO ORANGE HELIODOR, AND GREEN BERYL.
COLORLESS TOPAZ TO SKY BLUE TOPAZ (ONLY TOPAZ OF PEGMATITIC ORIGIN).

THE BENEFITS

• GOOD PRICES OF ENHANCEMENT
• THE MOST WELL ACCEPTED ENHANCEMENT AROUND THE WORLD , FREE OF RULES OF NCR – NUCLEAR REGULATORY COMMISSION FOR IRRADIATED GEMSTONE TRADE.
• SMOOTH COLORS – TONES, SHADES, AND HUES THAT LOOKS LIKE TO THE NATURAL GEMS ONES .
• SOME GEMSTONES ENHANCEMENT ARE NOT IDENTIFIED BY GEMOLOGICAL LABORATORIES, THEY ARE SCIENTIFICALLY CONSIDERED ONLY AN ACCELERATION OF NATURAL COLOR RADIATION PROCESS .
• SO MANY QUANTITIES CAN BE PROCESSED BY A SHORT PERIOD OF TIME (OVER A TON OF GEMSTONES).
• THE COMPANY HAS 6 DIFFERENT SYSTEMS OF GEMSTONE ENHANCEMENT PROCESSES (METHODS).

http://www.cbesa.com.br

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Last edited by Egor Gavrilenko on Thu Mar 10, 2011 9:27 am, edited 1 time in total.

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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Thu Mar 10, 2011 9:07 am 
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Hi Egor and thank you for posting the pdf.
Despite he doesn't post very often, Mauricio Favacho is a forum member..... 8)
ciao
alberto

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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Thu Mar 10, 2011 9:35 am 
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wow .... now I got al LOT of answers ! ..... thank you :)

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 Post subject: Re: Lemon quartz and prasiolite - (all) irradiated??
PostPosted: Tue Oct 11, 2011 11:31 am 
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Thanks for asking the question and subsequent sea of information. I am currently visiting Pakistan from San Diego. I am wondering if someone on the forum can get me in touch with someone who is willing to help few PHD students to take this treatment research in Pakistan. I will be meeting few scientist who are involved in food sanitation through cobolt 60 process and see if i can sponsor some PHD programs here .

There is some commercial work done in Lahore Pakistan for treatment but most of it is not academically recorded. I believe Pakistan scientist can contribute their share in this research if provided some commercial entities like ours to back their research.

Thanks for any help.


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