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 Post subject: Lab created ametrine?
PostPosted: Wed Nov 09, 2016 9:50 pm 
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I recently saw an online offering of ametrine wherein it was claimed that lab created ametrine did not exist so therefore the offered material had to be natural. I was under the impression that lab material had all but replaced the natural in the market. Does lab ametrine exist?


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 Post subject: Re: Lab created ametrine?
PostPosted: Thu Nov 10, 2016 2:01 am 
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I found this PDF a while back:

GIA - Russian Synthetic Ametrine

-Allan

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 Post subject: Re: Lab created ametrine?
PostPosted: Thu Nov 10, 2016 3:38 am 
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It is very common, though natural material isn't too hard to come by. Probably about like normal amethyst that way. The produced zoning is still somewhat limited so some natural stones can be readily distinguished.

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 Post subject: Re: Lab created ametrine?
PostPosted: Thu Nov 10, 2016 6:20 am 
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I once bought a nice ametrine which had a very good natural look.
However, after a while and a bit of thinking, the zoning distribution in the stone made me suspicious.
The color zoning is different in relation to C axis in natural and synthetic stones.
So with the help of a polariscope and refractometer, and observing at the same time the color separation, you can understand that something goes wrong.
I wanted to be absolutely sure so I took my stone to a lab. It was synthetic.
The seller was - looked - surprised but gave me my money back.


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 Post subject: Re: Lab created ametrine?
PostPosted: Thu Nov 10, 2016 6:54 pm 
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