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#JOTW Mozambique paraiba tourmaline in Leon Mege French cut ring
- Thread starter Art Nouveau
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Art Nouveau
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
Treenbean, Linda W and Arcadian: Thank you for your nice comments. I really appreciate them. I am enjoying my ring and I am glad I decided to go with the French cuts instead of a halo.
LindaW: What happened to more pictures of your gorgeous new pad ring and pendant. We are still waiting. If I can post pictures of my old hands, you can too.
AN
Treenbean, Linda W and Arcadian: Thank you for your nice comments. I really appreciate them. I am enjoying my ring and I am glad I decided to go with the French cuts instead of a halo.
LindaW: What happened to more pictures of your gorgeous new pad ring and pendant. We are still waiting. If I can post pictures of my old hands, you can too.
AN
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
Laila619, CharmyPoo & ForteKitty: Thank you for you kind compliments. It means a lot that you like my ring. I hope Charmy's LM ring will turn out perfect the second time around.
I just want to share one more photo that I snapped with my iphone today while I was inside the Apple store. This is what I meant earlier that sometimes when the light hits the stone at a certain angle, all you see is mostly the glow of the color and the facet junctions disappear. I have never seen this happen to my other color stone rings. I think it's kind of a neat phenomenon. This photo has not been edited with Photoshop.
AN
Laila619, CharmyPoo & ForteKitty: Thank you for you kind compliments. It means a lot that you like my ring. I hope Charmy's LM ring will turn out perfect the second time around.
I just want to share one more photo that I snapped with my iphone today while I was inside the Apple store. This is what I meant earlier that sometimes when the light hits the stone at a certain angle, all you see is mostly the glow of the color and the facet junctions disappear. I have never seen this happen to my other color stone rings. I think it's kind of a neat phenomenon. This photo has not been edited with Photoshop.
AN
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
Mochi: Glad you like the stone. It took a long time to find one that is affordable. I like your 'play' on words. That's cute.
MissyDebby: Thank you for thinking so highly of my ring. Leon did a super job. I am sure your next LM ring will turn out to be a masterpiece too.
Mochi: Glad you like the stone. It took a long time to find one that is affordable. I like your 'play' on words. That's cute.
MissyDebby: Thank you for thinking so highly of my ring. Leon did a super job. I am sure your next LM ring will turn out to be a masterpiece too.
Love Street
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
Coming back to visit because your ring has jumped to the top of my "favorites" list and I want to keep it on page 1.
So gorgeous! What does it look like in sunlight? And what size are you (obviously slim) fingers, if you don't mind my asking? It's just all so beautifully proportioned!!
Coming back to visit because your ring has jumped to the top of my "favorites" list and I want to keep it on page 1.
So gorgeous! What does it look like in sunlight? And what size are you (obviously slim) fingers, if you don't mind my asking? It's just all so beautifully proportioned!!
Burberrygirl
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Art Nouveau
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
D&T Lovestreet adn Burberry Girl: Thanks for your nice compliemnts. I am overwhelmed by flattering responses on this thread.
D&T, thank you for posting my tourmaline LM ring in the "Eye candy" thread.
Lovestreet: I have big hands. My right ring finger is size 6. My left ring finger is size 5. To give you an idea of proportions, I have posted a picture of the loose stone (~5.5 ct) on my hand next to my 4 ct radiant cut diamond with halo. Please excuse my unmanicured nails. The tourmaline looks best (most saturated and glowy) under halogen, incandescent and spot lights. It looks somewhat less saturated and more blue under daylight and fluorescent light. Under direct bright sunlight, the stone is so bright you see white spots and blue and green together. It looks better under indirect sunlight. I haven't gotten around to doing a photo shoot outside under bright sunlight, so I don't have any photos to post. Most of the pictures I have posted were taken indoors in a room with bright daylight. The ones on the Lalique dish were taken under halogen light.
D&T Lovestreet adn Burberry Girl: Thanks for your nice compliemnts. I am overwhelmed by flattering responses on this thread.
D&T, thank you for posting my tourmaline LM ring in the "Eye candy" thread.
Lovestreet: I have big hands. My right ring finger is size 6. My left ring finger is size 5. To give you an idea of proportions, I have posted a picture of the loose stone (~5.5 ct) on my hand next to my 4 ct radiant cut diamond with halo. Please excuse my unmanicured nails. The tourmaline looks best (most saturated and glowy) under halogen, incandescent and spot lights. It looks somewhat less saturated and more blue under daylight and fluorescent light. Under direct bright sunlight, the stone is so bright you see white spots and blue and green together. It looks better under indirect sunlight. I haven't gotten around to doing a photo shoot outside under bright sunlight, so I don't have any photos to post. Most of the pictures I have posted were taken indoors in a room with bright daylight. The ones on the Lalique dish were taken under halogen light.
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
Thanks AN ! You do NOT have big fingers, and your radiant is also gorgeous!! The tourmaline sounds so intriguing. If I ever move to colored stones down the line, it will be because of this ring. It just seems so mesmerizing and intriguing and flat out gorgeous.
Thanks AN ! You do NOT have big fingers, and your radiant is also gorgeous!! The tourmaline sounds so intriguing. If I ever move to colored stones down the line, it will be because of this ring. It just seems so mesmerizing and intriguing and flat out gorgeous.
Tacori E-ring
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
What is left to say since everyone else has used all the adjectives that I would come up with to describe your ring? (stunning, gorgeous, beautiful, work of art etc.) You must be ecstatic! I sure would be. Can I ask where the stone came from?
What is left to say since everyone else has used all the adjectives that I would come up with to describe your ring? (stunning, gorgeous, beautiful, work of art etc.) You must be ecstatic! I sure would be. Can I ask where the stone came from?
Raymond Polichano
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
So gorgeous. I've seen this in person and can't get it out of my mind. AN you have an amazing collection. But I have to admit, this is my favorite piece (which is saying a lot considering what there is to chose from). So freaking stunning. And no where near 'sinster' in real life. I don't think Leon's pics to do it justice.
So gorgeous. I've seen this in person and can't get it out of my mind. AN you have an amazing collection. But I have to admit, this is my favorite piece (which is saying a lot considering what there is to chose from). So freaking stunning. And no where near 'sinster' in real life. I don't think Leon's pics to do it justice.
CharmyPoo
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
That is an unbelievable ring. Absolutely stunning. I would not be able to wear it because I wouldn't stop staring at it; I would be the one at the traffic signal where everyone behind me is beeping because the light has turned green (yep, its happened before, but this ring would put me in major jeopardy).
I also want to say that while I get your concern and surprise by what you thought would be single prongs with double claws, it is perfect as is. The double prong is such an integral component to the basket design and makes the basket really, really handsome. I can't imagine not having them; it would be too simple for such an elegant ring, if that makes any sense. And the stone - very, very handsome and one of the best I've seen from the Mozambique find. Excellent, excellent job.
That is an unbelievable ring. Absolutely stunning. I would not be able to wear it because I wouldn't stop staring at it; I would be the one at the traffic signal where everyone behind me is beeping because the light has turned green (yep, its happened before, but this ring would put me in major jeopardy).
I also want to say that while I get your concern and surprise by what you thought would be single prongs with double claws, it is perfect as is. The double prong is such an integral component to the basket design and makes the basket really, really handsome. I can't imagine not having them; it would be too simple for such an elegant ring, if that makes any sense. And the stone - very, very handsome and one of the best I've seen from the Mozambique find. Excellent, excellent job.
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Re: Mozambique paraiba tourmaline in Leon Mege French cut ri
Your ring is awesome!
Paraiba is one state in Brazil where I live.
Paraiba tourmaline is a small stone that is considered to be both rare and precious. These gems are found in the Federal Brazilian State of Paraiba and are found in turquoise to green colors that are unmatched by any other stone found in the world. These legendary stones are real treasures to the people who own them.
Paraiba tourmaline has a unique vividness that is extraordinary, in colors of green and blue, however different than green tourmaline in clarity and transparency. It was only discovered in the 1980s by a man named Heitor Dimas Barbosa. Barbosa spent many years digging in the pegmatite galleries in the modest hills of Paraiba. He spent all of these years digging because he was absolutely convinced that he was going to find something that was new and different. It took him over five years of digging to find the rare tourmaline.
The tourmaline is in the trigonal crystal family and is long, slender to thick prismatic and columnar in its original state. It is distinguished by a prism which is three sided and is the only stone known to man that comes with only three sides.
The classic country of tourmalines is Brazil, and at one time this gemstone came in various colors until the classic turquoise color was discovered by Barbosa. The splendid turquoise color is a result of the copper content, which is an element that has never before been found in a natural stone. Scientists have also discovered that the stone will often contain manganese. High proportions of copper are responsible for the very coveted radiant turquoise and green hues and the violet and red tones come from those stones that contain manganese. Laboratories have discovered a burning technique that removes manganese and leaves the copper concentration to produce a pure, vivid color stone.
The vivid color of the Paraiba tourmaline is not present until the stone has been cut. Once cut and faceted they reveal an unusual glow that is often described as fire. The stones are a product of nature that is both fresh and high spirited and will positively flash with radiance. It does not require an expert to discern these qualities.
In a very short time the popularity of the Paraiba tourmaline became known across the world. The prices of the gemstone continue to rise, as does the demand. The stones are usually small but rarely a large one is found. These are extremely coveted and expensive. There are actually very few gem merchants in the world that carry this precious stone in their inventory.
It is often customary to use a treatment on tourmaline stones to alter or improve their color. This is especially true for the gems that are pink to red in color. The treatment is called irradiation and is practically impossible to detect. This type of treatment does not affect the final value of the stone. If the stones are enhanced to improve clarity, this must be revealed to the buyer before purchase. Once a stone has been enhanced in clarity it is worth a lot less money than one that is naturally non-treated.
The Paraiba tourmaline made its debut appearance in the gemstone world at an annual Tucson, Arizona gem show in the early 1990s. The stone was an immediate hit with some of the best specimens selling for as much as $3,000 a carat. At the time this price was thought to be very high, but by today’s standards that is a relatively low price. The market demand remains strong and the supply of the stone is limited. This drives up the value of the stone immensely. The popularity of the stone has laboratories working furiously to come up with ways to enhance the clarity and still remain acceptable within the gemstone community.
Paraiba tourmalines from Brazil are among the rarest and sought after gems in the world. Needless to say, they are also one of the most expensive.
http://www.jewelry-industry-guide.com/directory/fine-jewelry.htm
Hype Around The Paraiba
Paraiba Tourmalines are just one of several tourmalines available on the gem market today. Included in the tourmaline family are Rubellites, Indicolites, Pink Tourmaline, Green Tourmaline, and Multicolored or Watermelon Tourmaline.
What makes the Paraiba Tourmaline popular even to the uninitiated jeweler, is its unique glow. This precious stone has a glow that can only be described as “neon” and “electric
Nomenclature of "Paraiba" Tourmaline
The Association of Gemmological Laboratories (AGL) in Japan currently specifies that a blue-togreen tourmaline showing the characteristic "neon" color due to copper can only be called "Paraiba" as a trade name on an identification report when the stone is confirmed to be from Brazil. AGL allows the "Paraiba" name to be used for tourmalines from Rio Grande do Norte (Mulungu and Alto dos Quintos), since separating them from Mina da Batalha stones is difficult, and material imported into Japan is a mixture of tourmalines from both states. This policy is consistent with that advocated by most gem dealers who are handling the Brazilian "Paraiba" tourmaline. However, as supported by the research reported in this article, Cu-bearing tourmalines from Brazil, Nigeria, and Mozambique are difficult to distinguish from one another by standard gemological testing methods. Therefore, AGL and the Laboratory Manual Harmonization Committee (LMHCJ decided to reconsider the nomenclature for "Paraiba" tourmaline. The LMHC consists of representatives from the AGTA-Gemological Testing Center (U.S.), CISG (Italy), GAAJ Laboratory (Japan), GIA Laboratory (U.S.), GIT-Gem Testing Laboratory (Thailand), Gubelin Gem Lab (Switzerland), and SSEF Swiss Gemmological Institute (Switzerland). At the LMHC's October 2005 meeting in Lucerne, and at the February 2006 Gemstone Industry & Laboratory Conference in Tucson, the LMHC group agreed to define "Paraiba" tourmaline as a blue ("neon" blue, or violet), bluish green to greenish blue, or green elbaite tourmaline containing Cu and Mn, similar to the material that was originally mined in Paraiba, Brazil; any "Paraiba" tourmaline, regardless of its geographic origin, shall be described with the following wording on a gem identification report:
■ Species: Elbaite
■Variety: Paraiba tourmaline
■Comment: The name "Paraiba tourmaline" is derived from the locality where it was first mined in Brazil.
■Origin: Origin determination is optional
This policy is consistent with current CIBJO practice, which defines "Paraiba" tourmaline as having a "green to blue color caused by copper," but no definition is made according to locality. Thus, CIBJO also considers "Paraiba" tourmaline to be a general variety or trade name.
At present, AGL will fall into step with the recommendation of the LMHC group, and will disclose a new nomenclature for "Paraiba" tourmaline later this year.
CONCLUSION
Since the initial discovery of magnificent brightly colored tourmaline at Mina da Batalha in Brazil's Paraiba State, Cu-bearing elbaite has also been mined from Brazil's Rio Grande do Norte State (Mulungu and Alto dos Quintos), as well as in Nigeria and Mozambique. Overlap in the gemological properties and chemical compositions of tourmaline from these localities makes it difficult to distinguish their geographic origins with the testing techniques available in most gemological laboratories.
The common presence of yellowish brown needle-like growth tubes in the Nigerian tourmalines is suggestive of their origin. Also, native copper was most commonly seen in the Nigerian and a few Brazilian tourmalines, but thus far it has not been documented in stones from Mozambique.
This study has shown that chemical fingerprinting by the LA-ICP-MS technique is useful for distinguishing Cu-bearing tourmaline from the various localities. Geochemical plots of CuO+MnO versus Ga+Pb, CuO+MnO versus PbjBe, and Mg-Zn-Pb reveal that quantitative data for these elements may permit a reliable distinction of Brazilian stones from their counterparts mined in Nigeria and Mozambique. The Nigerian tourmalines contained larger amounts of the trace elements Ga, Ge, and Pb, whereas Brazilian tourmalines were enriched in Mg, Zn, and Sb. The Mozambique samples showed high contents of Be, Sc, Ga, and Pb, and Bi, but a lack of Mg.
Although the major laboratories have agreed to use Parafba tourmaline as a trade name for blue ("neon" blue, or violet), bluish green to greenish blue, or green Cu- and Mn-bearing elbaites, some labs may wish to provide the additional service of establishing the precise country of origin. On the basis of the research completed to date, such a distinction usually requires quantitative chemical analysis. As further discoveries are made in other parts of the world, additional research will be needed to reconfirm the criteria or establish new ones.
The above is an excerpt from Gems and Gemology Magazine, Volume XLII, Spring 2006, entitle: "Paraiba"-Type Copper-Bearing Tourmaline from Brazil, Nigeria and Mozambique: Chemical Fingerprinting by LA-ICP-MS
Your ring is awesome!
Paraiba is one state in Brazil where I live.
Paraiba tourmaline is a small stone that is considered to be both rare and precious. These gems are found in the Federal Brazilian State of Paraiba and are found in turquoise to green colors that are unmatched by any other stone found in the world. These legendary stones are real treasures to the people who own them.
Paraiba tourmaline has a unique vividness that is extraordinary, in colors of green and blue, however different than green tourmaline in clarity and transparency. It was only discovered in the 1980s by a man named Heitor Dimas Barbosa. Barbosa spent many years digging in the pegmatite galleries in the modest hills of Paraiba. He spent all of these years digging because he was absolutely convinced that he was going to find something that was new and different. It took him over five years of digging to find the rare tourmaline.
The tourmaline is in the trigonal crystal family and is long, slender to thick prismatic and columnar in its original state. It is distinguished by a prism which is three sided and is the only stone known to man that comes with only three sides.
The classic country of tourmalines is Brazil, and at one time this gemstone came in various colors until the classic turquoise color was discovered by Barbosa. The splendid turquoise color is a result of the copper content, which is an element that has never before been found in a natural stone. Scientists have also discovered that the stone will often contain manganese. High proportions of copper are responsible for the very coveted radiant turquoise and green hues and the violet and red tones come from those stones that contain manganese. Laboratories have discovered a burning technique that removes manganese and leaves the copper concentration to produce a pure, vivid color stone.
The vivid color of the Paraiba tourmaline is not present until the stone has been cut. Once cut and faceted they reveal an unusual glow that is often described as fire. The stones are a product of nature that is both fresh and high spirited and will positively flash with radiance. It does not require an expert to discern these qualities.
In a very short time the popularity of the Paraiba tourmaline became known across the world. The prices of the gemstone continue to rise, as does the demand. The stones are usually small but rarely a large one is found. These are extremely coveted and expensive. There are actually very few gem merchants in the world that carry this precious stone in their inventory.
It is often customary to use a treatment on tourmaline stones to alter or improve their color. This is especially true for the gems that are pink to red in color. The treatment is called irradiation and is practically impossible to detect. This type of treatment does not affect the final value of the stone. If the stones are enhanced to improve clarity, this must be revealed to the buyer before purchase. Once a stone has been enhanced in clarity it is worth a lot less money than one that is naturally non-treated.
The Paraiba tourmaline made its debut appearance in the gemstone world at an annual Tucson, Arizona gem show in the early 1990s. The stone was an immediate hit with some of the best specimens selling for as much as $3,000 a carat. At the time this price was thought to be very high, but by today’s standards that is a relatively low price. The market demand remains strong and the supply of the stone is limited. This drives up the value of the stone immensely. The popularity of the stone has laboratories working furiously to come up with ways to enhance the clarity and still remain acceptable within the gemstone community.
Paraiba tourmalines from Brazil are among the rarest and sought after gems in the world. Needless to say, they are also one of the most expensive.
http://www.jewelry-industry-guide.com/directory/fine-jewelry.htm
Hype Around The Paraiba
Paraiba Tourmalines are just one of several tourmalines available on the gem market today. Included in the tourmaline family are Rubellites, Indicolites, Pink Tourmaline, Green Tourmaline, and Multicolored or Watermelon Tourmaline.
What makes the Paraiba Tourmaline popular even to the uninitiated jeweler, is its unique glow. This precious stone has a glow that can only be described as “neon” and “electric
Nomenclature of "Paraiba" Tourmaline
The Association of Gemmological Laboratories (AGL) in Japan currently specifies that a blue-togreen tourmaline showing the characteristic "neon" color due to copper can only be called "Paraiba" as a trade name on an identification report when the stone is confirmed to be from Brazil. AGL allows the "Paraiba" name to be used for tourmalines from Rio Grande do Norte (Mulungu and Alto dos Quintos), since separating them from Mina da Batalha stones is difficult, and material imported into Japan is a mixture of tourmalines from both states. This policy is consistent with that advocated by most gem dealers who are handling the Brazilian "Paraiba" tourmaline. However, as supported by the research reported in this article, Cu-bearing tourmalines from Brazil, Nigeria, and Mozambique are difficult to distinguish from one another by standard gemological testing methods. Therefore, AGL and the Laboratory Manual Harmonization Committee (LMHCJ decided to reconsider the nomenclature for "Paraiba" tourmaline. The LMHC consists of representatives from the AGTA-Gemological Testing Center (U.S.), CISG (Italy), GAAJ Laboratory (Japan), GIA Laboratory (U.S.), GIT-Gem Testing Laboratory (Thailand), Gubelin Gem Lab (Switzerland), and SSEF Swiss Gemmological Institute (Switzerland). At the LMHC's October 2005 meeting in Lucerne, and at the February 2006 Gemstone Industry & Laboratory Conference in Tucson, the LMHC group agreed to define "Paraiba" tourmaline as a blue ("neon" blue, or violet), bluish green to greenish blue, or green elbaite tourmaline containing Cu and Mn, similar to the material that was originally mined in Paraiba, Brazil; any "Paraiba" tourmaline, regardless of its geographic origin, shall be described with the following wording on a gem identification report:
■ Species: Elbaite
■Variety: Paraiba tourmaline
■Comment: The name "Paraiba tourmaline" is derived from the locality where it was first mined in Brazil.
■Origin: Origin determination is optional
This policy is consistent with current CIBJO practice, which defines "Paraiba" tourmaline as having a "green to blue color caused by copper," but no definition is made according to locality. Thus, CIBJO also considers "Paraiba" tourmaline to be a general variety or trade name.
At present, AGL will fall into step with the recommendation of the LMHC group, and will disclose a new nomenclature for "Paraiba" tourmaline later this year.
CONCLUSION
Since the initial discovery of magnificent brightly colored tourmaline at Mina da Batalha in Brazil's Paraiba State, Cu-bearing elbaite has also been mined from Brazil's Rio Grande do Norte State (Mulungu and Alto dos Quintos), as well as in Nigeria and Mozambique. Overlap in the gemological properties and chemical compositions of tourmaline from these localities makes it difficult to distinguish their geographic origins with the testing techniques available in most gemological laboratories.
The common presence of yellowish brown needle-like growth tubes in the Nigerian tourmalines is suggestive of their origin. Also, native copper was most commonly seen in the Nigerian and a few Brazilian tourmalines, but thus far it has not been documented in stones from Mozambique.
This study has shown that chemical fingerprinting by the LA-ICP-MS technique is useful for distinguishing Cu-bearing tourmaline from the various localities. Geochemical plots of CuO+MnO versus Ga+Pb, CuO+MnO versus PbjBe, and Mg-Zn-Pb reveal that quantitative data for these elements may permit a reliable distinction of Brazilian stones from their counterparts mined in Nigeria and Mozambique. The Nigerian tourmalines contained larger amounts of the trace elements Ga, Ge, and Pb, whereas Brazilian tourmalines were enriched in Mg, Zn, and Sb. The Mozambique samples showed high contents of Be, Sc, Ga, and Pb, and Bi, but a lack of Mg.
Although the major laboratories have agreed to use Parafba tourmaline as a trade name for blue ("neon" blue, or violet), bluish green to greenish blue, or green Cu- and Mn-bearing elbaites, some labs may wish to provide the additional service of establishing the precise country of origin. On the basis of the research completed to date, such a distinction usually requires quantitative chemical analysis. As further discoveries are made in other parts of the world, additional research will be needed to reconfirm the criteria or establish new ones.
The above is an excerpt from Gems and Gemology Magazine, Volume XLII, Spring 2006, entitle: "Paraiba"-Type Copper-Bearing Tourmaline from Brazil, Nigeria and Mozambique: Chemical Fingerprinting by LA-ICP-MS
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