It’s official!
Ethiopia is a new source for paraiba tourmaline.
GIA and the Gübelin Gem Lab have now independently confirmed that Ethiopia is the world’s fourth geographic source of paraiba tourmaline. Their research shows that the Ethiopian material has a distinctive chemical fingerprint that readily separates it from paraiba tourmaline from Brazil, Nigeria and Mozambique.
Photo by Alisa Milakova, Gübelin Gem lab
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On August 27, GIA and the Gübelin Gem Lab
announced their conclusions in a joint press release.
→ Read the complete GIA/Gübelin press release here.
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For the colored gemstone trade, this is an extremely important discovery. Fine paraiba tourmaline is amongst the most valuable colored gemstones in the international market, and the arrival of a significant new source could have an important effect on availability — and perhaps ultimately the market itself.
How much?
But there is one enormous unanswered question: How much Ethiopian paraiba tourmaline is there?
The deposit is so new that no one yet knows whether the material now reaching the market represents a relatively limited discovery that could be quickly exhausted, or the beginning of a significant new source capable of producing paraiba tourmaline for years.
What the laboratories can now tell us is 1. what the material is — and 2. where it came from.
Two Laboratories, Two Independent Investigations
Reports of copper-bearing tourmaline from Ethiopia began circulating through the gemstone trade earlier this year. We wanted to know, and naturally, the laboratories wanted to know: Was it really paraiba? And was Ethiopia really the new source?
GIA and the Gübelin Gem Lab set out independently to find the answers, each acquiring its own reference samples and building its own analytical dataset.
Gübelin got its first clue in early May. Several paraiba tourmalines submitted to the lab showed an unusual chemical composition — one that didn’t match its reference data for Brazil, Mozambique or Nigeria.
Something was different.
Over the following weeks, Gübelin assembled approximately 300 rough and faceted stones from several independent sources. The collection included material obtained through a private dealer as well as samples acquired during a visit to Ethiopia by a senior Gübelin gemologist working with local dealers who had direct access to material from the mining area.
Meanwhile, GIA was seeing the new material as well. Its gemologists began examining parcels represented as Ethiopian in early June. Then, in July, the Ferreira Group provided GIA’s research department in Carlsbad, California, with more than 100 rough and faceted samples for detailed scientific investigation.
Neither laboratory rushed to make an announcement. Both waited until they were confident in the provenance of their samples and had accumulated sufficient analytical data.
Working separately, with independently acquired samples and their own research protocols, GIA and Gübelin arrived at the same conclusion.
And they found something particularly interesting.
including a 7.64 ct faceted stone and an 8.70 ct rough stone.
Courtesy of the Ferreira Group. Photo by Annie Haynes/GIA.
Vanadium
“What is most striking about the Ethiopian material is that despite considerable, complex chemical variation between individual samples, they share a remarkably distinct and coherent compositional signature,” said Dr. Peter Tollan, Head of R&D at the Gübelin Gem Lab.
And three elements in particular stand out:
Vanadium (V): greater than 60 ppm
Lead (Pb): 170–6,000 ppm
Gallium (Ga): 280–900 ppm
Together, those unusually elevated trace-element concentrations provide a chemical fingerprint that readily distinguishes the Ethiopian material from paraiba tourmaline originating in Brazil, Nigeria and Mozambique. Gübelin reports that the concentrations can be measured using a good-quality energy-dispersive X-ray fluorescence (ED-XRF) system.
GIA has reached the same conclusion.
“We can confidently identify Ethiopia as an origin on GIA Tourmaline Identification and Origin Reports,” said Dr. Aaron Palke, GIA senior manager of research and a noted colored stone expert. “We extensively documented the material’s characteristics, adding this important information to GIA’s expansive database of colored stone origin information.”
And this isn’t just research for some future laboratory service. GIA confirmed to the Roskin Gem News Report that it has already begun issuing reports identifying Ethiopia as the country of origin for qualifying material.
Origin Rather Than Color
But all that vanadium raised another question for us: Is it contributing to the color?
The Roskin Gem News Report asked both Palke and Tollan.
Probably not, was their response — or at least not significantly.
“We’ve seen some of these samples that appear to have a small vanadium-related peak in the UV-Vis spectrum, but it’s quite small and probably doesn’t affect the color significantly,” Palke told the RGNR.
Tollan reached a similar conclusion. “Based on our UV-Vis-NIR data, the elevated V concentrations don’t appear to have any substantial impact on the colour, but this is something we are still investigating,” he said.
to the Gübelin Gem Lab since 2017, plotted by date of submission.
The distinctly elevated V concentrations observed only in material from Ethiopia illustrate the utility of V
as a discriminator between Ethiopian paraíba tourmaline and material from other known geographic origins.
Image from Gübelin Gem Lab.
In other words, the vanadium appears to be much more important for telling us from where the tourmaline was dug up, rather than telling us why it looks the way it does with that strong to vivid color.
What Colors Are Coming From Ethiopia?
The material examined by GIA and Gübelin includes blue to bluish green stones as well as violet, purple and colorless material among some rough specimens. Many show pronounced color zoning accompanied by compositional variation.
But an important distinction needs to be made: Not every tourmaline coming from the new Ethiopian deposit is necessarily paraiba tourmaline.
Rough stones from the new Ethiopian tourmaline deposit
displaying the range of color for the stones being produced.
Stones weigh from 4.20 cts to 10.95 cts.
Courtesy of the Ferreira Group. Photo by Annie Haynes/GIA.
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The LMHC definition does not classify a stone as paraiba simply because it comes from the same deposit, nor merely because copper can be detected.
Qualifying paraiba tourmaline falls within a specified blue, bluish green to greenish blue, green or yellowish green color range and is colored mainly by copper and manganese. Iron-rich copper-bearing tourmaline in which iron dominates the relevant absorption spectrum does not meet the LMHC definition.
So the discovery of a paraiba-producing deposit in Ethiopia does not mean that every attractive blue or green tourmaline recovered there can automatically be sold as paraiba.
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Why Are We Spelling It “paraiba”?
You may have noticed something unusual in this article.
We are spelling the gemstone variety paraiba — without the accent and, except where normal capitalization rules require otherwise, with a lowercase “p.”
That’s intentional.
The Laboratory Manual Harmonisation Committee (LMHC), whose members include both GIA and the Gübelin Gem Lab, distinguishes in its standardized report wording between Paraíba, the Brazilian locality where the gemstone was first mined, and paraiba, the tourmaline variety name.
The distinction became increasingly important after copper- and manganese-bearing tourmalines meeting the definition were discovered outside Brazil.
According to LMHC Information Sheet #6, a paraiba tourmaline may be of “whatever geographical origin.”
In other words, Paraíba is a place. paraiba is a gemstone variety.
That means qualifying material can be paraiba tourmaline whether its geographic origin is Brazil, Nigeria, Mozambique — or now Ethiopia.
RGNR is following the LMHC nomenclature here: Paraíba for the Brazilian locality; paraiba for the gemstone variety.
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What Do We Know About the Deposit?
The precise geology of the new deposit is still being investigated.
“The deposit at Ethiopia more closely resembles the deposits in Mozambique rather than Brazil,” Tollan told the RGNR. “It is a highly weathered/altered secondary formation, although the exact nature of the deposit and the association with any primary host rock (highly likely a pegmatite) hasn’t yet been studied.”
Gübelin sent a senior gemologist to the area approximately two months ago. Tollan said security concerns prevented them from personally accessing the mine at that time, but he worked with local dealers and tradespeople with direct access to the mining area to obtain samples and detailed information.
Palke also pointed to the broader association between paraiba tourmaline and pegmatites.
“Geologically they’ll be quite similar,” he told the RGNR. “These are pegmatite hosted deposits where the pegmatite intrudes into country rock and forms large, often clean crystals that are suitable for gemstones.”
The distinguishing feature, he noted, is copper: these particular gem-bearing systems contain enough of it to produce paraiba tourmaline.
For now, however, the precise relationship between the Ethiopian secondary deposit and its primary source remains to be documented.
Brazil, Nigeria, Mozambique — and Now Ethiopia
The original discovery in Brazil’s Paraíba State in the late 1980s introduced the gemstone world to intensely colored copper-bearing elbaite tourmaline.
Copper-bearing tourmalines meeting the paraiba definition were subsequently identified in Nigeria and Mozambique, transforming what began as a locality-associated name into a recognized gemstone color variety that could originate from several countries.
Ethiopia now joins that list.
What remains unknown is potentially just as important as what GIA and Gübelin have established. How extensive is the deposit? What percentage of its production will qualify as paraiba tourmaline? And will meaningful production continue for months — or years?
Nobody knows yet.
Both GIA and Gübelin say they will continue expanding their reference collections as additional Ethiopian material becomes available.
The laboratories also plan to publish separate scientific papers detailing their independent investigations in an upcoming issue of GIA’s Gems & Gemology. Those papers will include the complete gemological, spectroscopic and chemical results, along with further discussion of geographic origin determination.
For now, one of the biggest questions has been answered.
Yes! Ethiopia has paraiba tourmaline!
But how much? That may be the next big story.
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Dr. Aaron Palke is Senior Manager of Research, Colored Stones at GIA in Carlsbad, California. A geologist specializing in colored-stone geology and geochemistry, his research includes geographic origin determination, gemstone formation, treatments and the causes of color in gemstones. Palke holds a Ph.D. in geology from Stanford University.
Visit GIA.edu.
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Dr. Peter Tollan is Head of Research and Development at the Gübelin Gem Lab in Lucerne, Switzerland. A geologist and geochemist, his research background includes mineralogy, petrology, trace-element chemistry and the application of advanced analytical techniques to minerals and gemstones. His research has appeared in scientific journals including Nature Geoscience and Nature Communications. At Gübelin, his work includes the application of geochemistry and analytical methods to gemstone identification and geographic origin determination.
Visit Gübelin Gem Lab.
Tap here to read the complete GIA/Gübelin press release.
