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 Post subject: Most faceted watermelon tourmaline are not.
PostPosted: Thu Feb 09, 2017 12:13 pm 
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I have been wondering around the inter net looking at faceted gemstone to appreciate the effort that is being put into cutting gemstones and selling them. Nothing is going to change my focus on cutting simple traditional cuts in tourmaline with an exceptional finish, but I get to see some exceptional faceting efforts. One of the things I did not wish to see is the abuse of the star of my show, tourmaline.

Now the abuse is so blatant that I wondered if it was even worth bringing it up to my audience of erudite readers, but when i see high quality establishments selling a tourmaline, declared to be a watermelon and it is not, is was enough. I think it is reasonable to say that watermelon tourmaline's color distribution is unique in the gemological world. It is certainly the only gemstone with concentric layers of color around the principle axis of its crystal, promoted by the trade. It is wonderful addition to the colorful world of tourmaline, but it is very difficult to actually find and effectively facet a watermelon tourmaline and demonstrate its unique qualities.

With an emerald cut, the need to have a competent rind that is thick enough and not too flawed, dominates the purchasing of a piece of rough for faceting. This along with a core that is colorful enough to be easily seen threw a table that is parallel to the principle axis makes appropriate rough quite uncommon, in my opinion. If you cut a round with its table perpendicular to the c axis it is again very rare to be able to keep a good amount or rind in the piece and the mixing action of the color of the core and the rind is not really desirable.

I just finished, only the second specimen of a faceted watermelon tourmaline in my collection. I was told it was a tourmaline with a pink principle axis and a greenish a/b axis by the stone's dealer, but I thought it would turn out to be a watermelon. And since I get to grind the stone, I get to see more than the seller. And what I saw was unusual. The core had a pink band like a squashed straw of richer color close to the center of it and a mostly grayish rind that graded in tone from very pale at the core to moderately dark at the surface of the crystal. On top of the that the integrity and relative thickness of the rind to the core was very good. Unfortunately the core was not perfectly centered, so in order to retain an relatively equal amount of rind on each side of the core, I had to manage the width of the stone and not go for maximum yeild.

So what do you get when you cut an emerald cut out of a watermelon tourmaline besides a lot of muddy juice. With luck you get nice alternating bands of core color and rind color with rmore rind color on either side of the core. Most of the flash and richer colors are in the ends, where to get to see the darker toned c axis colors. Did I see one single faceted gemstone like that on the inter net, no. What I saw were mostly tri color gemstones in large ratio emerald cuts. A minority were stout enough they might have been half of a slice of a ver5y large watermelon, but I doubt it. None showed a complete cross section of watermelon tourmaline. (Again I am only talking about faceted gemstones, not slices.)

I don't have a picture of my newest effort, but I do have a picture of the one I have had in the collection for years.
It is still the best example of a rare faceted gemstone. It is number 69 on my site BruceFryTourmaline.com.
Image
Or you can type watermelon into the search function and you get a really nice picture of it and a description. Jeff Smith, my friend who took all the photographs on my site, did a great job with the gemstone's color and tone on this one. Oh and the yellowish color you see in the ends is the mixing of the green (more blue green) rind and the pink core.

Bruce


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 Post subject: Re: Most faceted watermelon tourmaline are not.
PostPosted: Thu Feb 09, 2017 4:07 pm 
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In the trade most pink-green tourmaline bicolors are referred to as watermelon--they're not a full cross-section but more like an individual slice. It's one of those hills that isn't really worth dying on given how non-technical a trade term it is.
Other gems sometimes show this sort of zoning--my favorite alternative are sliced rubies with green fuschite or chrome paragonite rinds. But it is true nothing compares to tourmaline in color zoning (or color in general).

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 Post subject: Re: Most faceted watermelon tourmaline are not.
PostPosted: Thu Feb 09, 2017 9:00 pm 
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I was hoping to exclude any type of slice from the post because I can appreciate that any slice or part of a slice that had red and green in it would be a natural for the title of watermelon. But a fully faceted watermelon tourmaline is really a completely different animal. And if you stop in at my site brucefrytourmaline.com and search for it (#69), the real thing has a special beauty. A multicolored look that you may not have seen before.

Bruce


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 Post subject: Re: Most faceted watermelon tourmaline are not.
PostPosted: Thu Feb 09, 2017 9:48 pm 
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Yeah, don't get me wrong, what you managed here is exceptional (as is your usual standard). I just don't think it's necessarily wrong in faceted stones for more mundane pink green bicolors to hold the label given how difficult uncommon what you've done here is.

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 Post subject: Re: Most faceted watermelon tourmaline are not.
PostPosted: Thu Feb 09, 2017 11:26 pm 
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I glady conceed the point about the informal way tourmaline is presented to the public. There are so many exceptions to the generalized statements made by many authorities about tourmaline, that to make a big deal about it is counter productive. In other words it is really all about selling gemstones. As long as the public is getting the essential facts that determine the stone's value and care, it is OK.

Bruce


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 Post subject: Re: Most faceted watermelon tourmaline are not.
PostPosted: Fri Feb 10, 2017 11:05 am 
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My 7 color zone stone I just call tourmaline. Not a good photo.


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 Post subject: Re: Most faceted watermelon tourmaline are not.
PostPosted: Fri Feb 10, 2017 1:14 pm 
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Stephen Challener wrote:
In the trade most pink-green tourmaline bicolors are referred to as watermelon--they're not a full cross-section but more like an individual slice. It's one of those hills that isn't really worth dying on given how non-technical a trade term it is.
Other gems sometimes show this sort of zoning--my favorite alternative are sliced rubies with green fuschite or chrome paragonite rinds. But it is true nothing compares to tourmaline in color zoning (or color in general).


I've linked to your site directly above.


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 Post subject: Re: Most faceted watermelon tourmaline are not.
PostPosted: Wed Feb 22, 2017 3:31 pm 
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Quote:
nothing compares to tourmaline in color zoning


fluorite (but it's not suitable for jewellery)


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