Re: Radioactive Gemstones

[rkathren@tricity.WSU.edu (Ron L. Kathren)]

In response to your questions:

1.  Irradiation produces stable color centers (eg F centers) in the
crystalline lattice of the gemstone.

2.  You have described the basic technique.

3.  The regulations that generally apply to use of radiation sources apply.

Ron Kathren


 At 04:54 AM 11/28/98 -0600, Khalid Aleissa 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 not
>have a detail clear picture of the physical basis of this effect, but I
>know that the exposed stones are not radioactive (i.e., not activated)
>and this effect could be reversed by heating the stones to restore its
>original colors. On the other hand, I have heard that there are
>different irradiation techniques, which are followed in different places
>in the world, help increasing the prices of the gemstones by changing
>their features (inducing different colors, glowing ...etc.) at the same
>time they may induce radiation risk in these stones (!?). 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 govern these techniques?
>
>Answers and comments would be appreciated ...
>
>Best regards.
>--
>Khalid Aleissa, Ph.D.
>224B, Institute of Atomic Energy Research
>King Abdulaziz City for Science and Technology
>P. O. Box 6086
>Riyadh 11442
>Saudi Arabia
>Tel (+9661) 481-3617
>Fax. (+9661) 481-3887
>e-mail: kaleissa@kacst.edu.sa
>
>
>************************************************************************
>The RADSAFE Frequently Asked Questions list, archives and subscription
>information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
>
>

************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html