Paraíba Tourmaline Value Price and Jewelry Information - Gem Society

Paraíba Tourmaline Value, Price, and Jewelry Information.


Neon blue, 5.23-ct, cushion-cut paraíba tourmaline, Mozambique. Photo courtesy of liveauctioneers.com and Jasper52.


Discovered in 1989, paraíba tourmalines are among the world’s most prized gemstones. These rare gems are renowned for showing intense blue colors.


Paraíba Tourmaline Value.


Brazilian Cuprian (Paraíba) Tourmaline.


African Cuprian (Paraíba) Tourmaline.


Indicolite - Fine Color Blue: B 5/4.


Rubellite - Fine Color Red: R, slpR 6/5.


Chrome - Fine Color Green: vstbG, BG, vslbG 5/4.


Other Greens.


Other Tourmaline Types.


Other Tourmaline Types.


Cat’s Eye.


Other Cabochons.


Accompanying value information:


The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.


Currently, the paraíbas with the highest value have neon blue colors with strong saturation and medium tone. Many of these gems also have a secondary green hue. Slight green secondary hues won’t impact prices, but stronger hues will. Blue-green and green paraíbas usually hold less value than purer blue stones. (Popularly, paraíbas are associated closely with intense blue colors). Paraíbas with rarer colors, like pink, violet, and purple, don’t command higher prices because there’s less demand for them. (For pricing, treat stones with non-blue colors as non-cuprian tourmalines of those colors).


Neon green, 9.26-ct, brilliant pear-cut paraíba tourmaline, Mozambique. Photo courtesy of liveauctioneers.com and Kissing Auction.


For paraíbas, color is more important than clarity. Eye-visible inclusions are easily tolerated and only make slight value differences. On the other hand, cutting is critical. The gems need to be brilliant to obtain maximum value. Windowing and mediocre scintillation reduce value considerably. When grading paraíbas, color and brilliance are paramount. Top-value paraíbas should have exceptionally fine quality. Small differences in quality will make big differences in value.


Paraíbas from Brazil sell for much more than those from Nigeria or Mozambique. However, distinguishing the origins of paraíbas is difficult. Make sure you review a lab report for any paraíba identified as Brazilian before you buy it.


14k white gold pendant with a 23.61-ct African paraíba tourmaline center stone surrounded by 1.64 ctw white diamonds. Photo courtesy of liveauctioneers.com and Windsor Auctions Live.


Consult our paraíba tourmaline buying guide for more information.


Paraíba Tourmaline Information.


Data Value Name Paraíba Tourmaline Is a Variety of Tourmaline Colors Neon blue, greenish blue, blue-green, green, mint green, and, very rarely, violet, purple, and pink. Fracture Conchoidal, uneven Hardness 7-7.5 Cleavage None Wearability Very Good Crystallography Hexagonal (trigonal) Refractive Index 1.603-1.655 Birefringence 0.013-0.024 Dispersion 0.017 Luminescence Usually weak to inert. Luminescence Present No Absorption Spectrum Usually not diagnostic for tourmalines. However, for paraíbas, look for a broad area of general absorption starting at 600 nm. (Present only in gems with high copper content). Pleochroism As elbaite: On the o axis: blue-green/blue. On the e axis: light green to purplish/colorless to pink to purple. Optics o = 1.619-1.655; e = 1.603-1.634. Uniaxial (-). Optic Sign Uniaxial - Luster Vitreous to resinous Specific Gravity 2.84-3.10 (average 3.05) Enhancements Heating (common), laser drilling, filling (occasionally) Typical Treatments Fracture/Cavity Filling, Heat Treatment, Laser Drilling Transparency Translucent to transparent Phenomena Chatoyancy, 4-ray asterism (these effects are rare, chiefly because paraíbas rarely receive cabochon cuts); some specimens may show color change. Birthstone October Formula Elbaite: Na(Li 1.5 Al 1.5 )Al 6 (Si 6 O 18 )(BO 3 ) 3 (OH) 3 (OH,F) + Cu, Mn Etymology Named after the source of the original discovery, the Brazilian state of Paraíba. Occurrence Tourmaline occurs in crystalline schists; in granites and granite pegmatites (especially elbaite). African paraíba tourmalines are also found in alluvial deposits from weathered host rock. Inclusions Like most tourmalines, paraíbas usually contain inclusions. See the main Tourmaline gem listing for more information.


A color suite of paraíba tourmalines from Brazil, dating from 1991, total weight 5.41 cts. Photo © Joel E. Arem, PhD, FGA. Used with permission.


The Discovery of Paraíba Tourmaline.


In 1989, exceptionally brightly colored tourmalines were discovered in the state of Paraíba, Brazil . Researchers determined that these elbaite tourmalines received their intense coloration from copper. (The stones also contained manganese and often a bit of bismuth). These stones generated great excitement, and their prices soon exceeded $20K per carat.


Blue-green cuprian tourmaline crystal (paraíba), 1.8 x 1.6 x 1.2 cm, Batalha mine, Sao Jose da Batalha, Salgadinho, Borborema, Paraíba, Brazil. © Rob Lavinsky, www.iRocks.com. Used with permission.


Soon after the original discovery, similar tourmalines were found in Brazil’s Rio Grande Do Norte state, just north of Paraíba state.


Nigeria.


In 2000, more tourmalines also colored by copper were discovered in Nigeria . Generally, the Nigerian gemstones didn’t have the same vivid saturation as the Brazilian material. However, the range of colors did overlap.


Neon blue, 1.38-ct, oval-cut paraíba tourmaline, Nigeria. Photo courtesy of liveauctioneers.com and ARF International Co., Ltd.


Mozambique.


A few years later, still more copper-bearing tourmalines were discovered, this time in Mozambique . They also had colors similar to the Brazilian material.


Mint green, 1.51-ct paraíba tourmaline, Mozambique. Photo courtesy of liveauctioneers.com and Jasper52.


Liddicoatite Paraíbas.


In 2010, the Gübelin Gem Lab analyzed faceted cuprian-bearing liddicoatite tourmalines, possibly from Mozambique, with colors and concentrations of copper and manganese like elbaite paraíbas. In 2022, the Gemological Institute of America (GIA) analyzed similar specimens. These gemstones have appeared in gem markets. However, like most tourmalines, cut paraíbas belong predominantly to the elbaite species.


The Name Game.


From the beginning, the gem trade labeled the stones from Paraíba as paraíba tourmalines, after their source. The Rio Grande Do Norte tourmalines were also called paraíba.


However, naming the Nigerian gems posed a bit of a problem. Many in the trade would like to have them called “paraíba-like,” or “copper-bearing” (cuprian) tourmalines. Unfortunately, soon after the discovery of the Nigerian material, many of these stones were mixed with the Brazilian material. So, making distinctions between the Brazilian and Nigerian stones became complicated. The discovery of Mozambique material added another layer of difficulty, but these were commonly called “paraíba tourmalines from Mozambique.”


Visually, the best samples from Nigeria or Mozambique had colors that were as vivid as the ones from Brazil. Also, the chemical differences between stones from these sources are so slight that it’s often impossible to determine the origin without quantitative chemical analysis with advanced lab testing, such as laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS).


Defining Paraíba Tourmaline.


In 1999, before the Nigerian discoveries, the World Jewellery Confederation (CIBJO) modified their rules, allowing “paraíba” as a valid trade name. Traditionally, minerals often receive their name as a reference to the place where they were first encountered, so calling all the copper-bearing elbaite tourmalines “paraíba” was easily accepted.


In February 2006, the International Gemstone Industry Laboratory Conference accepted the term “paraíba tourmaline” as a variety name, regardless of geographic origin. In April 2006, the international Laboratory Manual Harmonization Committee (LMHC) also accepted the new terminology.


As a result of these events, most gem labs now call all copper-bearing elbaite “paraíba tourmaline.” Many lab reports will note that this is a variety name that doesn’t necessarily denote origin.


Reports from the American Gem Trade Association (AGTA) contain the following information:


SPECIES: Natural elbaite tourmaline VARIETY: Paraíba tourmaline ORIGIN: the source (if known) or not determined COMMENTS: the variety name paraíba is derived from the locality in Brazil where it was first mined. Its geographical origin has not been determined and therefore could be from Brazil, Mozambique, Nigeria or another locality.


14k white gold ring with a 6.5-ct, oval modified brilliant-cut paraíba tourmalines and accent diamonds. Photo courtesy of liveauctioneers.com and Kissing Auction.


Identifying Paraíba Tourmalines.


Paraíbas are elbaite tourmalines colored by copper (except, of course, liddicoatite specimens). They have a refractive index (RI) of 1.603 to 1.655 and specific gravity (SG) of 2.84 to 3.10. They have a high birefringence of 0.013 to 0.024, so you’ll almost always see doubling with your loupe. (See the main tourmaline gem listing for the properties of liddicoatites).


Paraíba colors are mostly green to blue. However, Mozambique has produced some pinks and purples. The main color criterion, however, is the saturation level, from 4, “Moderately Strong,” to 6, “Vivid.” Tones range from medium light to medium dark.


Chrome tourmalines are the only other tourmalines that approach a comparable saturation level (5). However, these gems have a higher RI, 1.772 to 1.778, and a much lower birefringence, 0.006. So, if you find an elbaite tourmaline with a saturation level of 5 or higher, you most likely have a paraíba.


On the other hand, if you have an elbaite with paraíba colors but a saturation of 4, you have to prove that it has copper content. A spectroscope reading will distinguish some of these gems. The key feature is a broad area of general absorption starting at 600 nm, present only in copper-bearing gems. However, a standard spectroscope will only distinguish stones with the highest copper content. Send the others to a major gem lab for testing.


Enhancements.


Paraíbas may receive heat treatment. This will lighten stones with darker tones and change violet and purple colors into blues.


Although clarity doesn’t play a major role in paraíba value, these gems may still receive clarity treatments. For example, lasers can remove dark inclusions, and fillers may decrease the visibility of surface fractures. However, stones with evidence of clarity treatments will hold less value than untreated gems of similar qualities. As a result, paraíbas don’t receive these treatments very often.


Blue, heat-treated, 9.55-ct, trillion-cut paraíba tourmaline, Brazil. Photo courtesy of liveauctioneers.com and 888 Auctions.


Avoid cleaning paraíba tourmalines with ultrasonic or steam devices. Vibrations and heat may cause liquid inclusions to expand, shattering the stone. Instead, use a soft brush, mild detergent, and warm water.


See our main gem listing on tourmalines as well as our gemstone jewelry care guide for more recommendations.


Platinum ring with five prong-set, oval mixed-cut paraíba tourmalines. Photo courtesy of liveauctioneers.com and Seized Assets Auctioneers.

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