Inclusions:Natural, Treated, Synthetic, and Imitation Opals

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Barbra Voltaire, FGG
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Inclusions:Natural, Treated, Synthetic, and Imitation Opals

Post by Barbra Voltaire, FGG »

in the latest edition of Gems & Gemology I found an article I think all our opal lovers will appreciate
Inclusions in Natural, Treated, Synthetic, and Imitation Opal
by Nathan D. Renfro, John I. Koivula, Jonathan Muyal, Shane F. McClure, Kevin Schumacher, and James E. Shigley


When gemologists think of opals, play-of-color is almost certainly the first characteristic that comes to mind (figure 1). While play-of-color patterns can be extraordinarily beautiful under magnification, opals often contain a vast array of spectacular microscopic features in addition to this phenomenon. In continuing G&G’s series on inclusions, this chart will focus on natural, treated, synthetic, and imitation opals.
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Do YOU have some opal pics taken with a scope? Please post them so we can discuss what we see.
Stephen Challener
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Re: Inclusions:Natural, Treated, Synthetic, and Imitation Op

Post by Stephen Challener »

Nice to see my opal on a chart like this :) The agatey one, photo taken by Nathan Renfro.
Rough and cut classic and exotic synthetic gems:https://store.turtleshoard.com
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Barbra Voltaire, FGG
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Re: Inclusions:Natural, Treated, Synthetic, and Imitation Op

Post by Barbra Voltaire, FGG »

Kewl, Stephen.
I grabbed an opal I cut when I was a teenager....very fond memories associated.
It was a scrap of black opal from Lightening Ridge given to me when I was 15.
The opal is still in good shape (albeit a bit remedial, cutting wise...weight retention was clearly my priority):
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I wasn't expecting this...with magnification:
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Ideas?
JackTrick
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Re: Inclusions:Natural, Treated, Synthetic, and Imitation Op

Post by JackTrick »

I have an Ethiopian opal that is covered in little dendritic inclusions (they look a bit like black pepper, no?)

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(from stone top)
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(from stone bottom)
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