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 Post subject: Birefringence question from Journal of Gemmology Vol.30 7/8
PostPosted: Sun Jan 30, 2011 5:42 am 
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Hi, can anyone help me with this question?

From The Journal of Gemmology, Volume 30 No. 7/8, July/October 2007.
Page 447, there are three graphs, for Gemstone A, Gemstone B and Gemstone C.
From these graphs, what is the birefringence of each stone and how is it worked out?

Thanks!


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 Post subject: Re: Birefringence question from Journal of Gemmology Vol.30
PostPosted: Sun Jan 30, 2011 1:13 pm 
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Can you scan the graphs and post the pic?


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 Post subject: Re: Birefringence question from Journal of Gemmology Vol.30
PostPosted: Sun Jan 30, 2011 1:34 pm 
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Hi,

Sorry, no scanner.
Is the birefringence always the diffence between alpha and gamma RI's? Also, if asked for birefrigence should we include a pos or neg sign if able to determine the optic nature?

Thanks again


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 Post subject: Re: Birefringence question from Journal of Gemmology Vol.30
PostPosted: Sun Jan 30, 2011 3:17 pm 
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Hi,

I see the same question has been asked on this thread:
Birefringence queston in assignment quiz GemA??

Thanks again and I'll wait for a reply here.


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