Re: Radioactive Gemstones

[Franz Schoenhofer <schoenho@via.at>]

At 04:53 28.11.1998 -0600, you wrote:
>Greeting to all RADSAFErs
>I feel that the issue I'm about to post may not be posted for the first
>time, therefore, I need you to patient and support me with what you know
>about it. I know that some of the gemstones are exposed to high doses of
>gamma rays or electron beams to induce or change their colors, I do  
-----------------------------------------


Does any body
>have information about:
>
>1. The physical basis of gemstone coloring by gamma rays or electron
>beams.
>2. Any irradiation techniques, other than the one mentioned in the first
>point, are used in gemstone industry.
>3. Are there any regulations.......................
-------------------------------

Dear collegue,

Yes, there was a little more than one year ago an intensive discussion
about this topic on radsafe - maybe it would be easierst to look up the
RADSAFE archives and search for "gemstones" or similar keywords. On the
other hand there was some time (maybe two years) ago an excellent article
in the journal "Radioactivity and Radiochemistry" (which I by the way
recommend anyway for its quality) on irradiation of gemstones, giving the
background informartion and showing excellent coloured pictures of the
various effects. Unfortunartely I do not have at the moment access to our
library, so I cannot give you the exact information about the volume, but I
know that KACST has an excellent library and literature search, so you
might easily retrieve the information. From the radiation protection point
of view only irradiation with neutrons is of concern, but to change
artificially the colour of a gemstone and sell it for a much higher price
should be considered fraud.

How are things going at KACST? I have been there nearly exactly a year ago
and remember not only the friendly atmosphere, but also the warm days and
nights - contrary to the situation now in my home country!

Best regards,

Franz Schoenhofer


Franz Schoenhofer
Habicherg. 31/7
A-1160 Vienna
Austria
Tel.: +43-1-495 53 08
Fax.: same number
mobile phone: +43-664-338 0 333
e-mail: schoenho@via.at

Office:
Federal Institute for Food Control and Research
Department of Radiochemistry
Kinderspitalg. 15
A-1095 Vienna
Austria
Tel.: +43-1-40 491 520
Fax.: +43-1-40 491 540
e-mail: schoenhofer@baluf.via.at
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