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 Post subject: Tricolored zoned topaz
PostPosted: Sat Jun 18, 2016 8:50 pm 
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From Skardu, Pakistan.
http://www.mindat.org/photo-755644.html


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 Post subject: Re: Tricolored zoned topaz
PostPosted: Sun Jun 19, 2016 5:25 pm 
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Joined: Mon Apr 02, 2012 9:31 pm
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Location: North Carolina
I'd guess it's just bicolored. This is very typical of irradiated pegmatitic topaz, especially from Pakistan. You can also sometimes see sector zoning and odd tigerstripes.

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 Post subject: Re: Tricolored zoned topaz
PostPosted: Sun Jun 19, 2016 6:51 pm 
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Hi Stephen,
The zones are colorless, red and yellow.
Here is another pic.
Image
... and another one, from a different angle, enabling a better view of the colorless zone
Image


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 Post subject: Re: Tricolored zoned topaz
PostPosted: Mon Jun 20, 2016 6:29 pm 
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Location: San Francisco
I've been resizing your pictures.
Please keep them to 650 px wide.
Thanks.


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 Post subject: Re: Tricolored zoned topaz
PostPosted: Mon Jun 20, 2016 7:06 pm 
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Look at how you're lighting it, though--the yellow zone is only on the side opposite to the light source. My guess would be that it's the c-axis color of the brown zone being flooded into the colorless rind.
One way or another, be sure to keep it out of the sun!

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 Post subject: Re: Tricolored zoned topaz
PostPosted: Tue Jun 21, 2016 10:01 am 
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Thank you Stephen. I'll do that.


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