CIBJO releases Gemmological Special Report: considers process of separating measurable facts from opinion; See Gemological Articles below.
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 Post subject: Alexandrite
PostPosted: Tue Oct 02, 2012 8:00 am 
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Hello There,

Can someone help me I have a faceted gem which gives me a R.I reading of 1.762 - 1.758

Also under a ultra light is green and blue along the sides, almost tourmaline green. If i take with my camera you can only see the pink.

Can anybody help me to explain how to see if its synthetic, know its a difficult question.

Thank you


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 Post subject: Re: Alexandrite
PostPosted: Tue Oct 02, 2012 11:22 am 
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alexander1 wrote:
Hello There,

Can someone help me I have a faceted gem which gives me a R.I reading of 1.762 - 1.758

Also under a ultra light is green and blue along the sides, almost tourmaline green. If i take with my camera you can only see the pink.

Can anybody help me to explain how to see if its synthetic, know its a difficult question.

Thank you


What do you mean by "ultra light"? UV light?


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 Post subject: Re: Alexanderite
PostPosted: Tue Oct 02, 2012 3:22 pm 
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Yes sorry under a UV light it goes like tourmaline green


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 Post subject: Re: Alexandrite
PostPosted: Tue Oct 02, 2012 9:01 pm 
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Alexandrite would fluoresce red under ultraviolet light.
And, color change is not determined by reaction to UV lights. It is measured by a difference in daylight vs. incandescent light, like candle light.
See
http://www.gemologyproject.com/wiki/ind ... lor_Change

Furthermore, the refractive index for alexandrite is 1.746 - 1.755, therefore, your unknown is neither natural NOR synthetic alexandrite.

If you are looking for an identification of your unknown, of course you understand, we can't help you.


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 Post subject: Re: Alexandrite
PostPosted: Wed Oct 03, 2012 5:38 pm 
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Thanks for the info.

Regards
Alex


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