The name game: Is origin the deciding factor?

by charlene_voisin | December 1, 2012 9:00 am

By Branko Deljanin

“What’s in a name? That which we call a rose by any other name would smell as sweet.” It is clear Shakespeare placed more emphasis on what something is, rather than what it is called. Yet, when it comes to gemmology and provenance, it would appear the lines are slightly blurry.

Take Paraiba tourmaline, for instance, which was at the centre of a $120-million lawsuit against the American Gem Trade Association (AGTA) and others a few years ago. The plaintiff—Paraiba.com—argued using the term ‘paraiba’ as a variety classification for similar stones from Mozambique and Nigeria diminished the value of the electric blue and green stone sourced from Paraiba, Brazil. Although a judge ultimately dismissed the lawsuit, the case stirred up debate around the provenance of gemstones, how it can affect cost, and the language labs use when referring to stones sourced outside Brazil exhibiting similar colouring and properties.

Why origin matters

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After the initial discovery in the 1980s of neon-coloured tourmaline at Mina da Batalha in Brazil’s Paraiba state, the trade and consumers alike were mesmerized by its unique electric glow. Demand grew and by the early 1990s, the mine was basically exhausted, making higher-quality gems extremely expensive. In fact, today, the finest specimens of two- to three-carats can top $20,000 per carat at the retail level.

Stones resembling the Paraiba gem were subsequently discovered in Nigeria and later in Mozambique, with both varieties containing copper and manganese, the elements responsible for the gem’s unmistakable neon colour. Since Nigerian and Mozambique stones are similar in colour to Paraiba tourmaline sourced from Brazil, various labs began referring to them as ‘paraiba,’ although it was unclear whether the term was being applied to describe variety or origin. Clearly, a regular green tourmaline mined in Paraiba could not be referred to as Paraiba tourmaline, even though it was mined there. Therefore, many saw the name as referring to not just origin, but also to a specific rich electric turquoise colour.

Outcry ensued among traders of Paraiba-sourced stones that using the term for all tourmaline with similar colouring diminished their value, since they are generally brighter in colour, of higher quality, and rarer. The court’s dismissal of the case left it up to gem labs to determine the terminology they use on their reports. Where one may deem a stone with sufficient levels of saturation and proper hue can be called ‘paraiba,’ another might simply call it ‘copper- and manganese-bearing.’ Some labs have taken to using the term ‘paraiba-type’ tourmaline when referring to the Nigerian or Mozambique variety. For the purpose of our discussion, we will use ‘paraiba’ to designate variety and ‘Paraiba’ when referring to origin.

With more neon-coloured tourmalines from Africa making their way to Canada, a closer look is in order.

Provenance and pricing

According to Renee Newman, author of Ruby, Sapphire & Emerald Buying Guide: How to Identify, Evaluate & Select These Gems, provenance can have a major impact on price when the following criteria are met:

1. The stone is of gem quality. While it does not have to be clean, the gem must be crystalline and not semi-opaque or translucent, and usually transparent, although there may be some exceptions where collectors will compromise on these qualities to complete their collection.
2. The source has produced stones of an exceptional quality that are difficult to find elsewhere.
3. The number of high-grade stones from the source is very limited.
   Rarity is important in pricing.
4. The stone is accompanied by a report from a respected lab(s) stating it is actually from the source indicated.

Four stones meeting these criteria and with extremely high premiums are:

• Kashmir sapphire;
• Mogok ruby from Burma;
• Russian alexandrite; and
• Paraiba tourmaline from Brazil.

Copper content

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Normally, tourmaline owes it various colours to the presence of iron, manganese, chrome, and vanadium. However, it is copper that gives Paraiba tourmaline the vibrant blue-green appearance everyone is familiar with, although manganese may be present and thought to impact colour. The interplay between these two elements gives rise to a variety of fascinatingly beautiful colours: emerald green, turquoise to sky blue, sapphire blue, indigo, bluish-violet, and purple. Yet, it is the electric blue-green colour that is held in highest esteem, as it is not seen in any other gem variety. This unique colour has helped gemstones from this particular source break all market records and write a whole new chapter in tourmaline history.

U.S. designer Brian Cook deals only with Paraiba tourmaline from Mina da Batalha, as he believes the colour to be more saturated than stones that come from mines in other parts of Brazil, as well as Mozambique and Nigeria. According to Cook, Mozambique produces very nice paraiba tourmaline, although it is generally priced lower than its Brazilian counterpart.

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Various studies conducted by a few laboratories specializing in coloured stones have shown that chemical fingerprinting through Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) can be useful for distinguishing copper-bearing tourmaline from the various localities based on the measurement of trace elements. Geochemical plots show that Nigerian tourmaline contains larger amounts of the trace elements gallium, germanium, and lead, whereas the Brazilian variety is rich in zinc, magnesium, and antimony.  Mozambique samples indicate higher contents of beryllium, scandium, gallium, lead, and bismuth, although no magnesium is present.

Heat is commonly applied to paraiba tourmaline to improve or change colour. Although evidence of heat is typically not discernible by microscopy (except for features like tension cracks along growth tubes), visible spectroscopy may indicate the stone has been treated. However, the criteria used by most laboratories to identify heat treatments are still not conclusive to positively distinguish treated stones from untreated.

You name it

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The Laboratory Manual Harmonisation Committee (LMHC) defines paraiba tourmaline as blue (i.e. neon blue or violet), bluish-green to greenish-blue, or green elbaite tourmaline containing copper and manganese, similar to the material that was originally mined in Paraiba, Brazil, although not necessarily originating there. As such, LMHC labs describe paraiba tourmaline on their reports using the following terminology regardless of geographic origin:

• Species: elbaite
• Variety: paraiba tourmaline
• Origin: origin determination is optional.

This is consistent with CIBJO, which defines paraiba tourmaline as having a “green to blue colour caused by copper.” Since it makes no mention of origin, CIBJO also considers paraiba tourmaline to be a general variety. In contrast, the American Gemological Laboratories (AGL) describes copper-bearing tourmaline from Mozambique or Nigeria as ‘paraiba-type.’ CIBJO and LMHC are the only two organizations I have found in my research that use paraiba tourmaline as a variety name for African cuprian tourmaline.

Some gemmologists believe lab reports should simply describe the stone and leave trade names to a company’s marketing department. At our lab, we avoid using paraiba tourmaline to designate variety on our reports, and instead indicate ‘cuprian tourmaline’ when copper is present. In my opinion, including a qualifying statement in the report’s comment section along the lines of “Known in the trade as paraiba tourmaline” when referring to neon blue-green tourmaline is acceptable. This is also the practice of labs like the German Foundation for Gemstone Research (DSEF).

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Alex Barcados, of C.D. Barcados in Toronto, says he doesn’t sell any tourmaline as simply paraiba without a discussion on the implications of origin. “Being able to explain the significance of the origin and the confusion surrounding the term ‘paraiba’ is part of our responsibility to our clients,” he says. “If the stone is mined in Brazil, we make it clear this adds value in the market. If it is not mined in Brazil, we explain the significance on its value. If copper is present and we feel the colour would qualify under the LMHC guidelines, we ensure the client is aware of the geographic implications on price. We also use the term ‘cuprian tourmaline.'”

Lisa Elser, a gem cutter based in Vancouver, shares her experience: “When I buy in Africa, no one can guarantee the rough is cuprian (although they say it is) and it’s not something that can be easily tested in the field. That means paying paraiba prices is silly, as the likelihood of getting it is slim. If it is not paraiba-type, I’ll have paid way too much for regular tourmaline.”

For gemstone buyers like Elser, portable advanced instruments such as visible-near infrared (VIS-NIR) spectrophotometers or X-ray fluorescence (XRF) spectrometers that can test for copper content may come in handy.

Legal issue

Paraiba.com sells tourmaline jewellery and gems using only stones originating from Paraiba, Brazil, and not what it calls “African lookalikes.” Since tourmaline from the Paraiba mine is limited, the value of existing stones has increased over time. In my opinion, using the term ‘paraiba’ to include stones from other sites dilutes the value of those sourced from Mina da Batalha.

Business profits aside, gemmologists themselves are divided on whether gems from African mines—or other mines that might be discovered—should be called paraiba. Sapphires from Kashmir or rubies from Mogok, Burma, for example, command some of the highest prices due to their superior colour, transparency, saturation, and rarity. In my opinion, labelling a ‘velvety blue’ sapphire from Sri Lanka as Kashmir sapphire is misleading, and the same can be said when using ‘Paraiba’ to refer to all neon tourmalines with copper and manganese.

What does this mean for jewellers?

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Since Paraiba tourmaline of Brazilian origin commands a high price, some sellers are likely to want to extend the reach of the word as far as possible, although most stones now available are in the .10- to .50-carat range. In general, Brazilian Paraiba can cost anywhere from five to 10 times more than the African variety.

Gemstone dealer Joe Menzie of Joe Menzie Inc., says larger Paraiba tourmalines are in short supply. “A five-carat Brazilian Paraiba could cost $50,000 per carat, while African material of a similar quality and size would not cost more than $10,000 per carat. The same African neon tourmaline would have cost a maximum of $3000 per carat just three years ago, but prices have increased as supplies of Brazilian material have dried up.” This is partly why he suggests that for larger stones, it makes sense to use Gübelin Gem Lab, the Swiss Foundation for the Research of Gemstones (SSEF), or AGL lab reports that clearly state the country of origin.

Ultimately, it is quality that gives tourmaline its value. If you are considering buying Paraiba tourmaline, it would be a good idea to consult an appraiser who regularly deals in this stone, is aware of the inconsistency regarding nomenclature, and is qualified to describe the colours appropriately, as well as judge values accurately.

In preparing this column, I consulted with colleagues for their opinion. Given the choice of buying neon tourmaline from Africa or Brazil, they all said that if the quality is the same, they would opt for the better-priced stones. They also said they did not understand why African neon tourmaline would still be referred to as paraiba on some lab reports, rather than paraiba-type. Perhaps for some people, copper content is important for green-blue tourmaline, but for true connoisseurs, the actual appearance and quality are what matter the most.

I believe the Paraiba tourmaline issue is fundamentally different than the question of provenance for, say, a Burmese ruby. All rubies mined in Burma are Burmese rubies (although Mogok mine has a better provenance), but not all tourmalines mined in Paraiba are Paraiba tourmalines. It is critical to understand that origin is important to the value of some gemstones, and that if you are going to pay a premium for origin, be sure to insist on proper testing and documentation.

The objective of labs and jewellers should be to ensure consumer confidence by using proper wording and disclosure of origin at point of sale. In other words, the end user should know what they are getting and that paraiba-type and Paraiba tourmaline are not the same thing.

The author would like to thank Alex Barcados of C.D. Barcados, Brian Cook of Nature’s Geometry, Joe Menzie of Joe Menzie Inc., Adolf Peretti of Gem Research Swisslab, Walter and Tiago Leite of Real Gems, Lisa Elser of Custom Cut Gems, authors Renee Newman and Richard Wise, and Bill Vermeulen of the Canadian Gemological Laboratory (CGL) for their contribution to this article.

[7]Branko Deljanin, B.Sc., GG, FGA, DUG is head gemmologist and president of Canadian Gemological Laboratory (CGL) in Vancouver. He is a regular contributor to trade and gemmological magazines and has presented reports at a number of research conferences. Deljanin is an instructor of standard and advanced gemmology programs on diamonds and coloured stones in Canada and internationally. He can be reached at info@cglworld.ca[8].

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