GIA Weighs In:
The Spring 2008 issue of GIA's Gems & Gemology features a full length article on Mozambique cuprian tourmaline. Under the heading “Nomenclature Issues” the authors, there are eight of them, four work for GIA, make the point that the now infamous Laboratory Manual Harmonization Committee (LMHC) has made it optional for its member to use the term Paraiba as either a variety designation or a trade name. The members of LMHC include AGTA, CISGEM, GAAJ, GIA, Gubelin and SSEF. Most members, they note, have opted to use Paraiba as a trade name. (Photo: above left: The real thing, 0.88 carat Paraiba Tourmaline from Paraiba, R. W. Wise collection)
A new wrinkle has been added. According to LMHC Information Sheet no. 6, Paraíba Tourmaline is defined as “a blue electric blue, neon blue, violet blue) or green elbaite tourmaline of medium to high saturation. That the gems have the proper chemistry, be copper and magnesium bearing is not sufficient. Violet, reddish-purple and yellowish green gems are excluded by definition and, say the authors, “The saturation necessary for blue-to-green Cu (Copper) bearing tourmaline to be considered ‘Paraiba’ does not have widespread agreement.” (Photo: above right: Exceptionally fine pair of Mozambique cuprian "Paraiba" tourmaline)
This definition offers up all sorts of interesting possibilities in the ongoing certificate game. One lab may decide that a given stone has sufficient levels of saturation and is of the proper hue to be called Paraíba while another lab might simply call it “Cu- and Mn-bearing.” This creates a situation similar to the LMHA decision regarding pinkish-orangy sapphires. Depending upon saturation, the lab may decide the stone is or is not padparadscha. For years now labs have been making a distinction between emerald and green beryl on the basis of saturation. This means that getting a Paraiba certificate on may be something of a crap shoot.
Reductio ad absurdum:
The decision to define the hue/tone of Paraiba tourmaline might have another embarrassing if unintended consequence. Gems from the original Paraíba mine, some of which, particularly the unheated material, was definitely in the violet and reddish purple hues described above, will no longer fit the definition of Paraiba tourmaline while stones of the appropriate hues from Mozambique and Nigeria will. Oh what a tangled web we weave!
Not Quite Like Padparadascha:
In a recent article The Paraiba Predicament posted on the Colored Stone website
www.colored-stone.com Editor in Chief David Federman draws a comparison between the current tourmaline terminology issue and a similar debate over the use of the term Padparadscha sapphire.
In the 1980s a large strike of fancy colored sapphire was found in the gem gravels of the Umba River in Tanzania. These included a portion of reddish-orangey-pink-brownish-red stones that were marketed as African Padparadascha. (Photo: left: 3.96 carat Natural Sri Lankan padparadscha sapphire, R. W. Wise, Collection) Many in the trade found this objectionable. In the 1983 article published in Gems & Gemology, legendary gemologist Robert Crowningshield defused the controversy by defining the color of padparadascha. This is correct. However, Federman goes on to say:
“Although "padparadscha" referred to color rather than place, it was always assumed that this corundum had one origin only: Sri Lanka. So use of the term "padparadscha" implied a single source.”
Federman’s analogy breaks down on a question of fact. Crowningshield did exclude Umba River stones from the definition not because they were from Africa but because, as he states in the referenced article, these gems were a brownish orange to deep orangy-red did not, therefore, fit the definition of padparadscha. Crowningshield did not exclude stones simply because they were not of Sri Lankan origin. The term padparadscha "implied" a single source only because, at that time there was but one source.
Since that article was published a number of natural stones from Vietnam and East Africa from newer sources have entered the market. These gems fit Crowningshield’s definition and qualify for the designation padparadscha despite lacking the traditional geographic lineage. Padparadscha as defined by Crowningshield as “light to medium tones of pinkish orange to orange-pink hue.” This is the same definition that I use in my book, Secrets Of The Gem Trade, and it has become universally accepted in the trade.
In his seminal Ruby & Sapphire, Richard Hughes appears to draw the same conclusion as Federman but goes on to say that “The best ‘padparadscha’ this author has seen was unearthed in Vietnam, not Sri Lanka.” He goes on to say that the best way to resolve the controversy would be to define the color range (p.398). Ironically, he suggests that a “set of printed color references” (ibid.). Two years ago, the LMHC came up with just such a set of color references which has generated its own set of problems. (see GemWise: Boldly Going...)
Well the best padparadscha this author has seen was found near Songea, Tanzania and who knows where the next one will come from. Actually a few stones from the old Umba River source also fit Crowningshield’s definition.
Just Do The Right Thing:
The fact is that none of the issues and absurdities associated with the current nomenclature would be issues at all if CIBJO and the labs had done it right in the first place. For the past fifty years every new gem that has come on the market has been named according to a simple convention. Though I am no fan of the ite word it has worked. Tanzanite, tsavorite, spessartite have done the job. With the new copper bearing Mozambique tourmaline a slight change is required. Since a mineral named cuprite already exists, cuprian as in cuprian elbaite tourmaline is the proper name.
We don't need lab gemologists to get into aesthetics or connoisseurship, areas for which they have not been trained. We don't need to exclude copper bearing stones from any source. We don't need another scandal. We don't need to confuse consumers. Try to explain the whole Pariaba thing and you will confuse buyers and confusing people is not a good way to market gemstones. We do need to knock of the BS.
Some say its too late, its a done deal, to that I say, nonsense! We all know that the naming of this gemstone is the result of a cynical and very well orchestrated attempt on the part of a group of dealers to hijack and build a marketing campaign on the good name of a very rare gemstone and we need to do it right.
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