October 3-7—JOSHUA TREE, CALIFORNIA: Annual show; Sportsmans Club of Joshua Tree
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 Post subject: Re: photo of clean stones...
PostPosted: Fri Sep 14, 2018 2:56 pm 
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By the way - If you go to John's website, not everything is high dollar material but it is all very well cut material.

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 Post subject: Re: photo of clean stones...
PostPosted: Fri Sep 14, 2018 4:43 pm 
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Nicky Newark wrote:
I believe that the question was- after watching the Jonn Dyer video, how well do you think the cut is on the bicolor tourmaline? Allow me to answer. The stone is badly windowed with a dead and lifeless center.The ability to see the mounting or newspaper print through the stone is not a good thing. Either all these expert appraisers and gemcutters are wrong or one of the most awarded gemcutters is wrong. I'm going with the clowns that say this is very well cut material.

This is not a window: Image
Windows aren't black (unless placed against a black background of course). In the case of this photo a window would be showing through as grey. My guess is we're seeing a reflection of the camera, or perhaps some extinction.
Either way, Steve has shared pictures of this stone before, which confirm it does not have a signficant window, though this one shows a similar pattern of extinction:
Image
I don't say this to suggest the stone has an excellent cut. For instance, I am assuming the line is a reflection off of the keel which isn't a good sign, and there are obvious things that can be said about the symmetry.


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 Post subject: Re: photo of clean stones...
PostPosted: Fri Sep 14, 2018 6:54 pm 
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Excessive extinction is also a cutting deficiency usually caused by too much bulge, and too deep of a stone, cut in an effort to save weight. There is a range of angles that a stone should be cut to, both too steep angles, and too shallow angles diminish the beauty and therefore the value.

So much to know....


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 Post subject: Re: photo of clean stones...
PostPosted: Fri Sep 14, 2018 7:16 pm 
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Steve 302, we all know you have a love of gems and a huge collection.

We are trying to educate YOUR eye or the eye of anyone who is following this thread on recognizing a well cut gem vs. a commercial cut.

It is not about blindly accepting (pun unintended) the opinion of a sycophant salesperson/appraiser or the compliments of a medical assistant.

It is about obtaining the skills to recognize quality cutting on your own. The ability to confidently look at a gem as an expert collector, not just a consumer.


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 Post subject: Re: photo of clean stones...
PostPosted: Fri Sep 14, 2018 8:17 pm 
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Here is a series of G&G articles that take very interesting direction on what is good and bad in cut. Not just "the only thing that counts is color and weight", yet not "perfect angles make perfect gems".

https://www.gia.edu/gia-news-research/value-factors-design-cut-quality-colored-gemstone-value-factors

https://www.gia.edu/gia-news-research-value-factors-gem-cutting-styles-definitions

https://www.gia.edu/gia-news-research-colored-stone-darkness-and-brightness

https://www.gia.edu/gia-news-research-some-factors-that-interact-to-affect-value

https://www.gia.edu/gia-news-research-colored-stone-cut-quality-what-to-look-for

https://www.gia.edu/gems-gemology/fall-2014-introduction-pleochroism-faceted-gems

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 Post subject: Re: photo of clean stones...
PostPosted: Sat Sep 15, 2018 6:37 am 
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I appreciate the responses on the postings of a very small selection of stones, i have actually very few items to photo, the pics i post are not the best, from now on no more pics, after the applause stops [a little sarcasm] & some of the views on pics that show a small portion of the stones, too many opinions are voiced on partial info as pictures only showing part of a stone in mountings or quick pics of a unmounted stone, no problem :(


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 Post subject: Re: photo of clean stones...
PostPosted: Sat Sep 15, 2018 8:48 pm 
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ruby302 wrote:
I appreciate the responses on the postings of a very small selection of stones, i have actually very few items to photo, the pics i post are not the best, from now on no more pics, after the applause stops [a little sarcasm] & some of the views on pics that show a small portion of the stones, too many opinions are voiced on partial info as pictures only showing part of a stone in mountings or quick pics of a unmounted stone, no problem :(

I really don't think a better quality photograph is going to change anyone's opinion as to the color and cutting of some of these stones. The olive green toumalines you posted stating that you and your appraisers feel that this is some of the best chrome out there is simply not true. I'm going to make a suggestion that you probably won't take ,but i'll try anyway. Go to the site of New Era Gems and look at their individual facet rough. Those guys are G.O. members, I use them and so do a lot of others. It seems that they are selling the Mehenge Garnet rough at a pretty good price. Next inquire about using one of the talented G.O. cutters to cut the stone. I have used a couple with very good results. You need to inquire because some will only use their own rough as well as some will do recuts and some don't. I guaranty this will be the finest stone in your collection , all done without breaking the bank. That stone might have the added benefit of being a limited production rarity like the Mozambique purples a couple years ago. I have quite a few precision cut stones but the bulk of my collection is just good commercial cut. Once in a while I will send a nice color out for a recut and the difference is amazing. Many years ago i came across an 11ct. trilliant shaped aquamarine that had the best vivid-deep sky blue color. It also had some of the worst cutting and polishing I have ever seen. The seller wanted 500 bucks , I offered a hundred -he took it. It went out to Jeff White for a recut {back when he'd did recuts} coming back as a 6ct. round brilliant. The stone sparkled like a 50 million dollar diamond. I think the point I'm trying to make is that if you make excellent color a priority ,even poorly cut stones can be fixed. One more bit of advice - take what ever money you normally put out for an appraisal and use it for a larger/better piece or rough.

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 Post subject: Re: photo of clean stones...
PostPosted: Sat Sep 15, 2018 10:49 pm 
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I'm not sure that picking rough is harder than choosing quality cut stones. Maybe a reach too far.


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