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Matched tri-color tourmalines; a quest for perfection

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zeolite

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Let’s begin an imaginary quest for perfection in bicolor tourmalines.


Bicolor tourmalines are not common. When you find them, the change in chemistry from one color to another seems to create thousands of inclusions. The average bicolor tourmaline looks as if it had been shot with a thousand shotgun pellets.


But if you search long enough you, can find ones that are flawless to the unaided eye. But let’s make the quest more difficult. You want both colors to be about equal tone. You don’t want one color strong and the other to be weak. For example, I have blue-colorless bicolor tourmaline crystals, that have not yet been cut, but they won’t match in tone.





bW5333.jpg
 

zeolite

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After you’ve found your fine bicolor, you need to have it re-cut, since certainly it would have been cut with a window. The crystals tend to be long and thin, and in native cutting, weight retention seem to be the top priority.


But that’s too easy. You’d like the color transition to be exactly in the center, and the crystals always have one long color and one short color. So you must cut away a lot of the perfectly good flawless long color to get the color transition in the center.


O.K. now we’re getting ready for Mission Impossible: you want a perfectly matched PAIR of perfect bicolor tourmalines!


Well, the two colors always vary from country to country. You must find a parcel from the same country, the same mine and possibly the same pocket of that mine to perfectly match the colors. It is best if you can sort through dozens or hundreds of crystals from one pocket, to get matching color. Then through that pocket, you try to find crystals or roughly equal length, width, depth of color and or course flawless.


Now you hand them to the cutter. He must cut the bottom of each one, stop on that stone and cut the bottom of the other stone, to match length, width, color transition line, while also removing any small flaws that might be in each crystal.


If he gets that far, without cracking the crystal, he can then cut the top of both stones, and do a final dimensional match. I bought three already cut bicolor tourmalines. I was trying make a suite: two matched tourmalines for earrings, and a larger bicolor for the pendant. Well, one stone of the earring pair cracked at the color transition line during re-cutting, and the suite was never completed! Nice try but it failed!


Below are a matched pair of tricolor tourmalines. The left gem is eye flawless, the right has a slight inclusion. If you view them face up, with them reflecting very brightly from the precision cut pavilions, you see only the two blue-green and pink-tan colors.




pair5330.jpg
 

zeolite

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But viewed way off axis, to reduce the bright reflections, you see a yellow transitional color between the two main colors. Notice the smooth imperceptible transition from one color to another; that is the magic of bicolors!


A wonderful idea for the setting is a line of tiny princess diamonds along one side only, along the length of each crystal. And the setting is two metals, white gold next to the cool color, and yellow gold next to the warm color.


This pair has to be mentally invented, then much search, and creation in cutting. You wouldn’t find this at your local Tiffany’s, Cartier, Bulgari, or Van Cleef & Arpels.




triside5331.jpg
 

chrono

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This is unbelievably cool! I like the smooth transition of the 3rd picture in addition to having both colours matched perfectly, centered with good colours on both ends.
 

Fly Girl

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Beautiful, beautiful pair. Thanks so much for sharing those. They are spectacular.
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I''m always looking for gorgeous pairs of stones. They are few and far between to begin with, then to get the great color match for those lovely bicolors is awesome.

I take it that I will be hunting for a matched set of bicolor tourmalines for the rest of my life.
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zeolite

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On the subject of matching gems, here is an aquamarine parure, cut in an opposed bar pattern. The earring stones are actually closer in tone to matching the center (pendant) gem than this picture shows.


parure is an entire wardrobe, or suite, of matching jewelry. Reserved for royalty and the wealthier classes, no woman was considered socially acceptable without a complete wardrobe of jewelry that defined her status, strength and political power.


Lovely word, much used in snooty Sotheby’s and Christie auctions “ Husband dear, please take time out from your foxhunting, to view these lovely trinkets from Sotheby’s”


aquaParure5335.jpg
 

Nomsdeplume

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Those are amazing! Wow! I''ve never seen anything like it.
 

LtlFirecracker

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Those are amazing. I was at Pala last weekend and saw some amazing watermelons and bi-colored. But I don''t think I saw any pairs.
 

D&T

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Seriously gorgeous! love the color transition
 

VRBeauty

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That pair is stunning! I take it they weren''t cut from the three crystals shown at the top of your post?

Do you cut your own stones, zeolite?
 

Barrett

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Nice!! the stones and pics look fantastic..love the way you wrote the thread too..good post!!!
 

marcy

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Beautiful stones.
 

zeolite

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Date: 8/15/2009 5:34:20 PM
Author: VRBeauty
That pair is stunning! I take it they weren''t cut from the three crystals shown at the top of your post?

Do you cut your own stones, zeolite?
I thank everyone for the good comments about the stones and AG about the write-up.

No, the three crystals are still colorless and (greenish)blue crystals. This matched pair was cut before I tried to make the 3 stone bicolor parure. And when one earring crystal cracked during recutting, I didn''t try to cut the larger pendant crystal down to match the other small bicolor that remained. I already had one matched pair and didn''t want waste flawless gem material to make a second pair. I''m going to try again later to buy and make a 3 crystal bicolor parure.

Yes. I cut all five of the gems pictured in this thread.
 

Arcadian

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awesome! I like those bicolor! BTW Mr Z, do you teach? Your style of writing lends itself to that profession.

-A
 

Sagebrush

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Zeolite,

Really nice job of bringing out the color.

Do you find that the average bi-color will part in a nice clean line perpendicular to the long axis of the crystal? I have lost several flawless Brazilian stones to that tendency in recutting.


Richard
 

zeolite

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Date: 8/16/2009 12:36:43 PM
Author: Arcadian
awesome! I like those bicolor! BTW Mr Z, do you teach? Your style of writing lends itself to that profession.

-A
Arcadian, that''s very kind of you. Actually I worked as a scientist in R&D for a large Fortune 50 U.S. company.

That company hired a writing consultant, who was assigned to read essays written by each employee, to critique their writing (keep in mind, I''m in a technical department). Her comment about my essay, was that my word order too regular (subject, verb, object), and that I needed more variety in word and clause order! As if I were interviewing for a position as a novelist, and not as a scientist!
 

zeolite

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Date: 8/16/2009 1:56:53 PM
Author: Richard W. Wise
Zeolite,

Really nice job of bringing out the color.

Do you find that the average bi-color will part in a nice clean line perpendicular to the long axis of the crystal? I have lost several flawless Brazilian stones to that tendency in recutting.


Richard
Thank you, Richard. Yes, they part exactly as you described!

My theory is that the unit crystal dimension changes, when one chromophore (iron - green) changes to another (manganese - pink), and that this mismatch of dimensions weakens the crystal.

I can't say I was surprised about it cracking. I've found the only crystal worse than kunzite (pink spodumene) about splitting, is bicolor tourmaline.
 

brandy_z28

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Amazing stones Zeo! I hope to see the finished blue-colorless bicolors when they''re cut.
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