Title: GSA 2016 Annual Meeting Abstract: A group shot of presenters in the oral and poster sessions. From left to right, Dr. Evan Smith (GIA), Dr. Christopher M. Breeding (GIA), Paul Johnson (GIA), Mandy Krebs (Univ. of Alberta), Dr. Karen Smit (GIA), Dr. Graham Pearson (Univ. of Alberta), Dr. Raquel Alonso-Perez (Harvard University), Dona Dirlam (GIA), Troy Ardon (GIA), Dr. Emmanuel Fritsch (Univ. of Nantes), Jullieta Lum (Univ. of Johannesburg), Dr. Jeffrey Post (Smithsonian Institution), Dr. Peter Heaney (Penn State University), Dr. Jim Shigley (GIA). Photo by Tao Hsu/GIA

The Geological Society of America (GSA) held its annual meeting September 25–28 in Denver, Colorado. This was the fourth meeting in which GIA hosted gemological technical sessions. In the oral and poster sessions, gemologists, geoscientists, and students from all over the world came together to present their research and discuss advanced topics.

The gemology oral session at GSA has been organized and sponsored by GIA since 2012. This year’s oral session was very well attended. Photo by Tao Hsu/GIA
Invited speaker Jeffrey Post (Smithsonian Institution, Washington DC) presented the results from detailed and sustained studies on a selection of significant fancy-color diamonds, including blue, pink and chameleon stones. Among these, the researchers applied time-of-flight secondary ion mass spectrometry (ToF-SIMS) analysis to the Hope diamond, which allowed the measurement of total boron concentration; the results revealed strong zoning from this chromophore in many blue diamonds. Graham Pearson (University of Alberta, Canada) reported on his study of the saline fluid inclusions preserved in some diamonds from the Ekati and Diavik mines and pointed out that alkali- and Cl-rich fluids play a key role in diamond formation. Invited speaker Emmanuel Fritsch (University of Nantes, France) discussed the state of synthetic diamond identification. He also noted the advantages and limitations of some of the most commonly used sorting methods.

Dr. Evan Smith from GIA reported his exciting inclusion findings in large top quality type IIa diamonds. Photo by Tao Hsu/GIA
GIA researchers shared their results on several diamond-related projects. Christopher M. Breeding showed the fluorescence colors and patterns diamonds can display when exposed to ultraviolet light. In addition to their beauty, these colors and patterns are important in diamond formation studies and the identification of natural, treated, and synthetic material. Karen Smit presented new data on a suite of canary diamonds from Sierra Leone. This will allow researchers to further specify the source fluids and color-forming defects of these yellow diamonds and better correlate their features to the unusual geological formation history of the Zimmi diamond deposit. Evan Smith reported his findings on inclusions in thousands of high-quality type II polished diamonds and trimmed-off portions. The recurring set of inclusions in many stones includes a metallic multi-phase assemblage and retrogressed former perovskite phases. Together, the two inclusion types revealed a unique paragenesis for these large, top-quality diamonds.

Dr. Jim Shigley (left), Dona Dirlam (center), and Dr. Wuyi Wang (right) have been the advocators for gemological technical session in GSA annual meetings for the past four years. Photo by Cathy Jonathan/GIA
Presentations on colored gemstone research revealed a variety of studies on important gem species and collector stones. Mandy Krebs (University of Alberta) reported on Pb-Pb geochronology of rubies and the first-ever radiometric age determination of ruby. This new method allows dating to be done directly on the ruby itself rather than on inclusions such as zircon. This dramatically broadens the application of geochronology in ruby provenance determination. Jullieta Lum (University of Johannesburg) presented major and trace element composition of emerald and aquamarine collected from central Namibia and South Africa. Peter Heaney (Penn State University) revealed the cause of iridescence in metamorphic hematite from Minas Gerais, Brazil. The study by Dr. Heaney and his former student Xiayang Lin found that this phenomenon is caused by a framework of well-oriented hematite nanorods. Raquel Alonso-Perez (Harvard University) presented preliminary results on the geochemistry of emeralds from the Irondro deposit in Madagascar.

Dr. Raquel Alonso-Perez from Harvard University reported the preliminary geochemistry study on emeralds from Madagascar. Photo by Tao Hsu/GIA
Important research on gemstone formation was also delivered. Yury Klyukin (Virginia Tech) addressed the valuable information fluid and melt inclusion studies can provide in solving gem formation problems, using diamond, emerald, and corundum as examples. Invited speaker David London (University of Oklahoma) discussed the different mechanisms that caused zonation within pegmatites. Understanding of mineral segregation within pegmatites is critical for gem exploration.

Dr. Graham Pearson discussed the results from fluid inclusion study performed on diamonds from Ekati and Diavik. Photo by Tao Hsu/GIA
The poster session presenters included two graduate students from the China University of Geosciences (Wuhan). Chengsi Wang proved the robustness of photoluminescence (PL) spectroscopy in treated and synthetic spinel identification through a series of heating and annealing experiments. Yuan Zheng applied linear discriminant analysis (LDA) in separating hundreds of turquoise samples from three different sources after analyzing their trace elements using ICP-MS.

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Poster Session
GIA diamond researchers and library staff also presented interesting discoveries in the poster session. Wuyi Wang studied the distribution of the [Si-V]– defect and found that it has a dramatically different correlation with Nii+ between natural and HPHT synthetic diamonds. Paul Johnson demonstrated that hydrogen-rich diamonds with intensive inclusions and fractures can be heated to generate a more uniform black color. Based on his experience, microscopic observation remains the most powerful tool in identifying this treatment. Troy Ardon and Sally Eaton-Magaña conducted a series of annealing experiments at different temperatures with two hydrogen-rich Zimbabwe diamond plates. They evaluated the effect of high temperature on the diamonds’ spectroscopic features and inclusions. Rose Tozer examined one of the rarest publications in the GIA library collection: Russia’s Treasure of Diamonds and Precious Stones. Edited by the well-known mineralogist A.E. Fersman, this book documents Russia’s regalia and crown jewels at the time of the February Revolution in 1917. The volume has been digitized as part of GIA’s project to digitize items from its rare book collection and can be accessed free of charge at https://archive.org/details/gialibrary.

The science discussion continued at the GIA hosted dinner reception. Presenters, guests and GIA Denver alumni attended this reception. Photo by Tao Hsu/GIA
Abstracts from the two gemological sessions can be found at https://gsa.confex.com/gsa
/2016AM/webprogram/Session40327.html (oral) and https://gsa.confex.com/gsa/2016AM
/webprogram/Session41331.html (poster). The 2017 meeting will be held October 22–25 in Seattle.

The 2017 GSA annual meeting is going to be held in Seattle, Washington. GSA will again host both oral and poster technical sessions. Photo by Tao Hsu/GIA Source: GIA @topic:7


Title: Multiphase Fluid Inclusions in Blue Sapphires from the Ilmen Mountains, Southern Urals Abstract: Figure 1. Map showing the location of the blue sapphire occurrence within Russia.
Most gem-quality sapphires are found in placers that originate from the weathering of primary deposits. Discovering a mineral in situ, or within the host rocks, is rare. In August 2015, some of the authors visited a corundum deposit in the Ilmen Mountains in the southern Urals of Russia (figure 1) to collect the stones in situ for research. This is a primary source where blue sapphire megacrysts are found exclusively in syenite pegmatites. The occurrence is located inside the Ilmen State Reserve, and its commercial exploitation is forbidden.

Corundum syenite pegmatites in the Ilmen Mountains present an REE-rich source of transparent to translucent blue sapphire crystals measuring up to 5.9 × 4.2 cm (figure 2). But the brittle deformation throughout the gem-bearing rocks, which appears to be linked to syntectonic and post-tectonic processes that occurred at the deposit and the surrounding area, increased the amount of fissures in the corundum. As a result, the sapphires are of a lower quality and can only be faceted into small stones. Six sapphire wafers and nine petrographic thin sections of mineral from corundum-bearing rocks of this occurrence were recently examined at GIA’s Carlsbad lab.

Figure 2. Sapphire crystals in feldspar matrix of a syenite pegmatite from the Ilmen Mountains of Russia. The largest sapphire crystal measures 5.9 × 4.2 cm. From a private collection; photo by Elena S. Sorokina.
Laser ablation–inductively couple plasma–mass spectrometry (LA-ICP-MS) and electron microprobe analysis (EPMA) indicated medium-rich Fe (2470–3620 ppmw), high Ga (190–280 ppmw), and low Mg (3–9 ppmw) with Ga/Mg 29, all in the range of magmatic sapphires (see J.J. Peucat et al., “Ga/Mg ratio as a new geochemical tool to differentiate magmatic from metamorphic blue sapphires,” Lithos, Vol. 98, No. 1–4, 2007, pp. 261–274).

Ferrocolumbite, zircon, and alkali feldspar group minerals, identified by confocal micro-Raman spectroscopy, were observed as syngenetic inclusions. Epigenetic muscovite and exsolved needles (most likely ilmenite) were found as well; along with syngenetic inclusions, they are common phases in mineral assemblages of Ilmen corundum syenite pegmatites (see V. F. Zhdanov et al., “The mineralogy of corundum pegmatite pit no. 298 of the Ilmen State Reserve,” Materialy k mineralogii Yuzhnogo Urala [Materials to Mineralogy of South Urals], AS USSR, 1978, pp. 92–97, in Russian). Wafers 200–400 µm in width were prepared in order to study fluid inclusions (FI) trapped within the sapphire crystals.

Using Raman spectroscopy, solid phases in needle and thin-film form were identified as diaspore (figure 3); both vapor and liquid phases were found to be CO2, with a Fermi doublet for the liquid phase at 1282.9–1283.2 and 1387.2–1387.6 cm–1, accompanied by less intense symmetrical bands (“hot bands”; see N.B. Colthup et al., Introduction to Infrared and Raman Spectroscopy, 2nd ed., Academic Press, New York, 1975) at approximately 1264 and 1408 cm–1 and a small band at 1370 cm–1 due to 13CO2. Raman spectra in the 2000–4000 cm–1 range did not show H2O-, CH4-, or N2-related bands. The less intense apparent maxima at 418, 578, and 750 cm–1 belong to sapphire vibration modes. The distance between Fermi doublet peaks (Δ) ranged from 104.1 to 104.4 cm–1 (again, see figure 10), occurring at about 0.7 g/cm3 CO2 density (see X. Wang et al., “Raman spectroscopic measurements of CO2 density: Experimental calibration with high-pressure optical cell (HPOC) and fused silica capillary capsule (FSCC) with application to fluid inclusion observations,” Geochimica et Cosmochimica Acta, Vol. 75, 2011, pp. 4080–4093). The distance was linked to the pressure at approximately 1.8 kbar for the trapping of fluid inclusions within the sapphire matrix (CO2 P-T isochores, or lines of constant density). The CO2 homogenization temperature (the temperature at which the fluid inclusion becomes a single-phase liquid or vapor) occurred in the liquid phase and measured between 30.1° and 30.7°C (figure 4), while the corundum-diaspore equilibrium was estimated at 510°–530°C (matching the previous estimation by V.A. Simonov, Usloviya mineraloobrazovaniya v granitnykh pegmatitakh [Conditions of Mineral Formation in Non-Granitic Pegmatites], Nauka, Novosibirsk, USSR, 1981, in Russian). Based on the determined pressure (around 1.8 kbar), the temperature of stability for the corundum-orthoclase-H2O system was higher than 690°C (H.S. Yoder and H.P. Eugster, “Synthetic and natural muscovites,” Geochimica et Cosmochimica Acta, Vol. 8, 1955, pp. 225–280), likely linked to the multistage geological history of blue sapphire crystallization along the P-T path in the Ilmen Mountains.

Figure 3. Raman spectra at room temperature of a fluid inclusion trapped in a sapphire
from the Ilmen Mountains: 12CO2 Fermi doublet along with hot bands and 13CO2 peak
(red trace), diaspore needle (blue), and a diaspore thin film (green). For 12CO2, the
average distance between Fermi doublet peaks (Δ) was calculated as 104.25 cm–1.
Diasp = diaspore, Sph = sapphire, Ilm = ilmenite, l = liquid CO2, v = vapor CO2.
Photomicrograph by Elena S. Sorokina; polarized transmitted light, field of view 0.288 mm.

Figure 4. Homogenization of CO2 in a fluid inclusion in sapphire from the Ilmen Mountains occurs in the liquid phase between 30.1° and 30.7°C. A: Homogenization of CO2 above 30.7°C. B and C: Vaporization of CO2 with a temperature below 30.7–30.1°C. D: The multiphase FI at room temperature. l = liquid, v = vapor. Photomicrographs by Jonathan Muyal; transmitted polarized illumination, field of view 0.72 mm.
Further study of these sapphires is needed to better understand the geological history of this locality, but the information obtained can provide valuable clues about the characterization of gem corundum from secondary placers. Source: GIA @topic:3


Title: The Fluid Art of Angela Conty Abstract: Figure 1. This pin/pendant features two Oregon sunstones, a Chinese freshwater pearl, and diamond accents. Carved green chalcedony and a 1.50 ct zircon complete the design. The piece is set in 14K and 18K yellow gold. Photo by Robert Weldon/GIA; courtesy of Angela Conty.

Renowned lapidary, designer, and goldsmith Angela Conty created a jewelry collection exclusively for the 2016 Tucson gem and mineral shows. We had a chance to see some of her convertible pieces at the Hotel Tucson City Center.

Ms. Conty’s artistic vision is heavily influenced by nature: Flowers, leaves, twigs, seed pods, and similar motifs are reflected in her work. The fluidity of her artistic expression strikes a perfect balance and flow between the gemstone carving and the jewelry design. Ms. Conty views her design and manufacturing process as the evolution of a work of art that often features a carved gemstone. Changes may occur when carving the stone, working the metal, or assembling the piece of art. When she has the rough in hand, she takes into consideration the stone’s shape, its best orientation, and how it would look carved and set in jewelry. As the carving progresses, the rough might take an unexpected direction, even after the metalwork is finished. She feels that lapidary work and metalsmithing must blend and harmonize in order to create the perfect balance. This means the carving or the metalwork can be continually adjusted until the carving is ready to be set. In her words, “I gather together elements, cast and constructed, and begin to solder or weld until the carving, gemstones and metalwork begin to work together, always ready to make more changes. I add, move, and remove elements to create a better integration of carving and goldwork.”

Her gemstone preferences include Australian opal, quartz, chalcedony, and her new favorite, Oregon sunstone. Her metal of choice is 18K gold, but she will sometimes use silver or 14K gold, depending on the design or the client’s preference. The relationship between the stone and metal is beautifully demonstrated in the Oregon sunstone jewelry pieces shown in figures 1 and 2, which can be worn as either brooch or pendant.

Figure 2. This 18K yellow gold convertible pendant/pin features a 46.80 ct carved Oregon
sunstone as its centerpiece. A chocolate Tahitian pearl drop and diamond accents help
frame the carving. Photo by Robert Weldon/GIA; courtesy of Angela Conty.
Ms. Conty’s combined talents in art and creative design took root more than 40 years ago at the State University of New York (SUNY) at New Paltz, where she earned undergraduate and graduate degrees in art. Her training included drawing, art history, painting, ceramics, sculpture, and silversmithing. She studied metalwork under Kurt Matzdorff, the founder of the Society of North American Goldsmiths (SNAG), and is a self-taught lapidary artist.

In 2002, Ms. Conty won second place in AGTA’s Cutting Edge Awards in the Objects of Art category. Her work has been featured in numerous publications and books. Source: GIA @topic:6


Title: Color Zoned Emerald Abstract: Figure 1. Left: When table-down, the stone is mainly colorless, showing some partially green overgrowth. Right: Face-up, the faceted stone displays an even and attractive dark green emerald color. Photos by Jonathan Muyal.

Cutting style and orientation are important considerations when cutting natural crystals with strong color zoning. Careful placement of these zones can distribute color by reflection, creating a uniformly colored finished stone when viewed face-up.

Recently, the Carlsbad laboratory received a 33.73 ct green octagonal step cut showing strong color zoning (figure 1). The gem cutter skillfully placed a thin green color zone in this emerald along the pavilion facets so that the stone would appear uniformly green when in a face-up position. Standard gemological testing revealed a refractive index (RI) of 1.571–1.578 and a specific gravity (SG) of 2.72. Chromium-related features were observed in the red end of the spectrum when examined with a handheld spectroscope. All of these properties were consistent with emerald. During microscopic examination, minute jagged fluid inclusions and growth tubes were observed, proving the stone was of natural origin (figure 2).

Figure 2. When viewed from the side, irregular green color zoning is observed along with
minute jagged fluid inclusions. Photomicrograph by Jonathan Muyal; field of view 14.52 mm.
Interestingly, the stone showed a strong green color zone very close to some of the pavilion facets, as well as hexagonal columnar-like growth and irregular zoning (figure 3). This type of zoning represents a late-stage influx of chromium and vanadium into the genetic environment, which were then incorporated into the crystal lattice of the beryl. Energy-dispersive X-ray fluorescence (EDXRF) revealed high levels of Cr and V in the green color zone, which was consistent with the observed color. Although similar zoning has been observed in emerald previously (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Volume 3, Opinio Verlag, Basel, Switzerland, 2008, pp. 433–434), the zoning in this specimen was quite distinct.

Figure 3. The colorless spots indicate parallel columnar growth of white beryl overgrown
by green emerald. Photomicrograph by Jonathan Muyal; field of view 19.27 mm.
This emerald demonstrates the significance of proper orientation and cutting style in fashioning high-quality gem materials. Source: GIA @topic:3


Title: Larger Optic Disks Abstract: Nature’s Geometry

In this video, Brian Cook explains the next step in the evolution of his unique optic disks: larger pieces that display a striking rainbow of concentric color bands.
At the 2014 GJX show, Brian Cook (Nature’s Geometry, Graton, California) showed us innovative optical disks made of colorless quartz featuring a drilled tube containing pieces of brightly colored gem and mineral rough. The tube is subsequently sealed with clear quartz. When the disk is viewed face up, the insert’s reflections permeate the disk with bright color.

For this year’s show, Cook’s “wheel of light” design evolved into larger sizes with more intriguing reflective effects. Seen front-on, the new disks produced concentric colored reflections. The first we saw measured approximately 4 cm (1.57 in.) in diameter and featured Brazilian emerald, Paraíba tourmaline, and haüyne insets (haüyne is a brittle sodium calcium sulfate that provides rich blues). One innovative feature is that the viewer could see different colors depending on the viewing direction. From various directions the disk was suffused with bands of rich green, electric blue, or royal blue color.

According to Cook, this new product takes the color and amplifies it. There is a chamber within the quartz, which he polishes before inserting the colors he wants. Because no faceting is involved, all the colors are blended together. Cook said his passion for Paraíba tourmaline was the starting point.

Figure 1. This edge-on view of the “wheel of light” reveals its construction. Photo by Duncan Pay/GIA; courtesy of Nature’s Geometry.
Cook unwrapped a larger disk, approximately 8 cm (3.15 in.) in diameter. Viewed edge-on, the chamber’s pattern of colored rough gems and minerals was revealed (figure 1). Cook had arranged a complete spectrum of rainbow colors in sequence: ruby, spessartine garnet, a gold nugget, Paraíba tourmaline, and haüyne (figure 2).

Figure 2. Seen end-on, the larger disk displays the spectrum as concentric colors. Photo by Duncan Pay/GIA, courtesy of Nature’s Geometry.
Cook also showed us a smaller optic disk set in a handmade platinum pendant set with diamond and melee-size Paraíba tourmaline from the Brazil Paraíba mine in Parelhas, Rio Grande do Norte. This piece combined the unusual optic effects of the center, which featured more Paraíba tourmaline and haüyne, with a conventional suite, which besides the pendant included a pair of earrings set with similar optic disks. Source: GIA @topic:1


Title: Fine Corundum, Demantoid Garnet Abstract: Figure 1. This unheated 8.56 ct intense pink sapphire represents the very best of recent production from Madagascar. Photo by Robert Weldon/GIA; courtesy of B&B Fine Gems.

At the AGTA show, Dave Bindra (B&B Fine Gems, Los Angeles) showed us some exceptional corundum, especially fine untreated yellow and pink sapphires.

The first standout piece Bindra showed us was an 8.56 ct unheated, intense pink sapphire of extremely high clarity from Madagascar. Under the lights of our photo studio, it showed an intense pink hue (figure 1). A gem of this quality might expect to realize a wholesale price in the region of $10,000 to $15,000 per carat. Bindra noted that Madagascar is producing some superb fancy sapphire, including pink, violet, and “padparadscha” colors.

	B&B Fine Gems

In this interview, Dave Bindra of B&B Fine Gems showcases fine pink and yellow sapphire, Mozambique ruby, and a superb suite of Russian demantoid garnet. He explains how increased consumption in markets outside the U.S. and Europe is affecting gem supply and forcing many colored gem dealers to turn to the “recirculated” market for their clients.
Although this pink gem represented recent production, Bindra explained that the secondary market has become an extremely important source for many dealers now that competition for freshly mined goods is so intense, particularly from buyers serving Asian markets. These recirculated gems coming back onto the market offer a way for dealers to procure stones that often surpass current production in size and quality, or are simply unobtainable today. As an example, Bindra cited an 89.55 ct unheated golden sapphire from Sri Lanka (figure 2), remarking that he had not seen material of this color emerge from the ground in Sri Lanka for more than 10 years. Originally this gem was somewhat larger, over 100 ct. Modern cutting reduced the weight slightly but produced a dramatic improvement in color and brilliance. Bindra described this gem’s appearance and stature as “world class.” As such, it would likely command a wholesale price in excess of $3,000 per carat.

Bindra next showed us a blend of new production and recirculated stones: a graduated suite of 12 perfectly matched Russian demantoid garnet round brilliants. Each gem contained a classic “horsetail” inclusion. Weighing in at 20 carats total, the suite took Bindra four years to complete. He described it as a special item, with the stones from the secondary market selected and recut to perfectly match the newer gems.

Figure 2. This exceptional unheated 89.55 ct golden sapphire from Sri Lanka is an example of a recirculated stone. Photo by Robert Weldon/GIA; courtesy of B&B Fine Gems.
For Bindra, Mozambique is the future of ruby production. He illustrated this with three fine heated gems from the Montepuez deposit weighing 7.05, 7.92, and 9.35 ct (figure 3). Although all three stones represented beautiful, clean material, he considered the 7.92 ct gem the finest, due to its superior brilliance and intense red hue. Due to the ongoing trade embargo with Myanmar, classic “Burmese” ruby is unobtainable for U.S. dealers. Fine Mozambique rubies like these in the 7–9 ct range are in high demand and exceptionally rare. Gems larger than 4 or 5 ct are increasingly hard to find, Bindra pointed out.

Figure 3. Left to right: These heated rubies from Mozambique weigh 7.05, 7.92, and 9.35 ct. Photos by Robert Weldon/GIA; courtesy of B&B Fine Gems.
Unlike Myanmar, Mozambique does not carry the stigma of human rights abuses. The heat treatment of these rubies is not an issue with consumers, either. As Bindra explained, the market for top natural unheated ruby has now reached such rarified levels that buyers are very receptive to high-quality heated rubies. (The current auction record is held by an unheated 8.62 ct Graff ruby, of Burmese origin, which sold for $8,372,094—or $994,040 per carat—at a Sotheby’s Geneva auction in September 2014.) Purchasing such expensive stones is a stretch even for the top 1% of consumers. By contrast, stones like the three Bindra showed us wholesale in the region of $35,000 to $50,000 per carat. He said gems like these are “quite consumable” and can be the centerpieces of wearable jewelry, meaning they will occasionally be seen outside of safe deposit boxes.

Bindra faces the same issue as many other colored stone dealers in Tucson: scarcity of new rough production due to intense competition between the U.S. market and buyers purchasing for Chinese consumers. This is the major driver for dealers looking for alternative sources of gems such as recirculated goods, he said.

The new wealth in China has created a different dynamic. For more than 50 years, American and European consumers have been the main buyers of fine gemstones, he explained. Now these established markets have competition, and Bindra and many of his colleagues in the business supply gems to these competitors as well. Besides China, other cultures—India, for instance—have a rich jewelry heritage, and consuming gems is ingrained. This trend is not going to change, so there will be more wealthy consumers in emerging markets that desire colored gems, and current producers will struggle to meet demand.

In terms of demand at the show, Bindra reported that rubies and unheated sapphires were quite strong. There was demand for anything rare and exotic, goods that the average consumer would not find elsewhere. He also saw renewed demand for emerald. In the past, he noted a “certain favoritism” toward Colombian emerald, but increased supplies of quality gems from Zambia have made it a much more popular source and established the “Zambian brand” in people’s minds. Source: GIA @topic:1


Title: Tucson 2015 Overview Abstract: Figure 1. Many sellers at Tucson were displaying very large, fine, or unusual gems that had been held in inventory for years. Photo by Duncan Pay/GIA; courtesy of Noor Gems Japan Ltd.

Once again, buyers and sellers from all over the world converged on a corner of the American Southwest for the annual Tucson gem shows. Many broad trends continued from 2014: Consuming markets are hungry for fine colored gems, and demand still outstrips supply, causing prices for some gems to reach new highs. As more buyers from Asia compete for new production of rough gemstones, the secondary market is becoming more important for domestic dealers. Many recycled gems and jewelry pieces were returning to the market through estate sales, or directly from owners lured by all-time high prices. Some sellers were showing items that had been held in inventory for years or even decades (figure 1). These included fine corundum, Imperial topaz, red spinel, and aquamarine. We noted that many of these “recirculated” goods were exceptional gems, superior to newly mined production. Many vendors are unable to source new production at prices their clientele are prepared to pay.

Cultured pearls of every type were in high demand—especially from the Chinese market. The same was true of rubellite and “watermelon” tourmaline, tsavorite, and spinel, especially red to pink material from Mahenge, Tanzania.

Overall, we observed several clear trends:

Many gem-quality stones were cut in nontraditional shapes such as cabochons, fantasy cuts, carvings (figure 2), and even slices.
Many jewelry pieces had an organic, natural feel. Similarly, non-round pearls—particularly large baroque shapes—were also everywhere. The freeform shapes of many opals also fit well with natural-shape trends for jewelry, lending themselves to carved flowers, animals, and abstract pieces.
Designers were seeking out unusual colors for standard gems: fancy-color sapphires, colored diamonds, tourmalines, spinel, garnets, zoisite, zircon, and beryl (morganite was very much in demand).
Many vendors told us they left their “traditional” inventory items at home, as they can sell those at any time. The Tucson crowd demands the unusual (figure 3), so vendors brought nontraditional items and were reportedly selling them at a good pace.
Even though red-brown “Marsala” was named the Pantone color of the year for 2015, it did not appear to be an overall favorite, with the most observed colors being bright blues, greens, and pinks.
The largest crowds observed at the wholesale shows were gathered at the booths selling nontraditional gem materials such as cabochons, druzy, tourmalinated and rutilated quartz (again, see figure 2), and crystal slices—material typically used in “craft” jewelry.
Opal (figure 4) was prominent: There was an abundance of Ethiopian hydrophane opal, Australian opal, Mexican fire opal, and material from the U.S. Recent finds in Ethiopia have generated a buzz for all types, according to several vendors.

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Figures 2-4
Foot traffic at the main AGTA and GJX shows appeared down from 2014, but most merchants reported brisk sales, especially of very fine or unique items. In fact, many vendors mentioned that this was their best show in recent years. Eric Braunwart of Columbia Gem House (Vancouver, Washington) said he had forgotten what a “good year was like” until this show.

Alexander Wild (Wild & Petsch Lapidaries, Kirschweiler, Germany) provided a broad-brush market update from his firm’s perspective. Rough prices for many gems continued on an upward trajectory, he reported. Just a few years ago, fine-color, high-clarity rubellite tourmaline sold at wholesale for $300 to $350 per carat. These numbers reflected the asking price for superb quality, with perhaps just a few tiny inclusions. In 2015, prices for equivalent material are almost triple that figure.

As in the previous year, sourcing rough gems remains a problem, although it is by no means impossible for established companies with good connections in source countries, such as Wild & Petsch. The company is able to source quality rough, though prices are definitely higher for many goods. Since mid-2014, prices for many other commodities such as oil and copper have fallen. But gemstone rough prices continue to rise, largely due to demand from China. In Wild’s opinion, such high prices are unsustainable. He wondered how long this would continue, asking rhetorically, “Is this a gem bubble?”

Asked what was in demand, he answered that it was the gemstones Wild & Petsch is known for: fine tourmaline and beryl. With their African connections, they secured a nice production of Paraíba-type copper-bearing tourmaline from Mozambique, along with good parcels of aquamarine. As a result, they were able to offer their clientele this material at what Wild considered very fair market prices. In contrast, supply of rubellite and pink tourmaline rough is quite difficult, and most of his supply has been coming from Nigeria. Brazilian rubellite is basically unavailable.

Figure 5. The Cruzeiro mine, the Miranda Group, and KGK work together to bring Brazil’s bicolor and rubelite tourmaline to the market in China. The Cruzeiro mine provides the rough to the Miranda Group, which cuts the material. Photo by Andrew Lucas; courtesy of Miranda Group Co. Ltd.
[Editor’s note: In a 2014 visit to Brazil’s Cruzeiro mine in Minas Gerais State, a GIA team witnessed recovery of large facet-grade rubellite crystals (figure 5), which were all put aside for exclusive sale to a consortium—composed of the Miranda Group and KGK—that fashions the material at its own factory in Shenzhen, China, for the Chinese market (figures 6 and 7). Only blue to green production was available for sale to local and export markets.]

Figure 6. Rough tourmaline crystals are sliced or sawn by the Miranda Group in Hong Kong, then faceted and polished at their factory in Shenzhen. Photo by Andrew Lucas; courtesy of Miranda Group Co. Ltd. (VRL: 179216)

Figure 7. Fine Brazilian rubellite tourmaline at the Miranda Group’s factory in Shenzhen—most of these cut stones are larger than 10 ct. The factory needs to receive 100 kilos of rough per month to meet production goals of 25,000 to 30,000 carats. KGK markets and sells the cut stones and also mounts them into jewelry for sale, primarily in China. Photo by Andrew Lucas; courtesy of Miranda Group Co. Ltd.
Adjusting to price fluctuations has always been part of life for colored stone merchants, Wild conceded, but not sudden, successive increases to levels that are three, four, or five times higher than the market was previously accustomed to (see www.gia.edu/gia-news-research-miranda-journey-of-rubellite-tourmaline).

Wild offered the possibility that at some point a single market will be satisfied—even one as large as China’s. When that happens, suppliers will have to find other markets for these goods. Wild believes the North American and European markets are more sophisticated in terms of pricing—especially for cut goods—than China’s current market. There is also the possibility that any political upheavals there could cause rough prices for certain gems to go down sharply, he said. And that could spell trouble for some miners who base their operations on today’s historically high rough gem prices.

Wild said business at the 2015 show had been better than the year before. He reckoned business was a third above 2014, with some big-ticket items—including a fine aquamarine suite—spoken for prior to the show. He confirmed our impression that traffic was down slightly from last year—possibly due to fewer Asian buyers or the winter travel difficulties on the U.S. East Coast.

Wild intimated that many clients came with specific requirements in mind, particularly aquamarine or Paraíba-type tourmaline, and selection was good for these gems at this year’s show. He mentioned they had even sold a few collectors’ pieces, including a beautiful large green step-cut beryl that measured more than 200 ct. That was a surprise to him, because such items have proven more difficult to sell the last few years.

“Everyone is searching for good things,” Wild concluded. “For the most part, we get what we need.” Asked if the trend is still toward finer, more unique pieces, Wild responded, “Absolutely. I think quality still comes first. A lot of the trends from last year still apply, and we’re still waiting to see if there’s going to be any deflation in pricing for some goods.”
Once again, G&G greatly appreciates the assistance of the many friends who shared material and information with us this year, with special thanks to the American Gem Trade Association for providing photography studio space during the AGTA show. Dr. Tao Hsu, Andy Lucas, Donna Beaton, Pedro Padua, and Dr. Jennifer Stone-Sundberg contributed to these reports. Source: GIA @topic:10


Title: Faceted Wurtzite from Tanzania Abstract: Figure 1. These wurtzites are from Merelani, Tanzania. The crystal measures 17 mm across, and the cut stones weigh 1.74 and 1.59 ct. Photo by Jaroslav Hyršl.

Wurtzite is the hexagonal polymorph of ZnS. It is far less common than sphalerite, the cubic polymorph of ZnS. All previously identified wurtzite has been opaque to translucent, and therefore not facetable. Layers of wurtzite and sphalerite can alternate in so-called Schalenblende, a colloidal sphalerite variety used only rarely for cabochons. The first transparent wurtzite crystals were found in 2012, at the tanzanite deposit at Merelani Hills, south of Arusha, Tanzania (for identification, see www.rruff.info). The crystals, which measure up to 2 cm in diameter, are very rare. They have a tabular shape, with pyramidal faces. Some crystals from Merelani have clean parts, and several gemstones were faceted from them (figure 1).

Eight cut stones weighing 0.30–1.74 ct were studied. They were orange-brown, with a submetallic luster and very weak, almost invisible, pleochroism. Refractive indices of these stones were well over the refractometer limit, listed as 2.36 and 2.38 in the literature (J. Bernard and J. Hyršl, Minerals and their Localities, Granit, Czech Republic, 2004, p. 666). They had very low birefringence, confirmed by a lack of doubling of facet edges. The determined specific gravity values of two of the crystals were 3.78 and 3.85; their measured hardness was 3.5. The stones were uniaxial positive and inert under both long- and short-wave UV. Their UV-Vis-NIR spectrum (figure 2) exhibited a high cut-off at 545 nm. The stones showed anisotropic crystals and hexagonal growth structures when viewed under a microscope. Because of the rarity and high value of the Tanzanian crystals, the faceted wurtzites are sure to catch the attention of gemstone collectors.

Figure 2. The UV-Vis-NIR spectrum of a 1.74 cut wurtzite from Tanzania. Source: GIA @topic:2


Title: Tucson 2014 Overview Abstract: View Gallery

Tucson draws buyers hungry for Earth’s treasures.
Every February, exhibitors and buyers from all over the globe descend on Tucson, Arizona, for the annual gem and mineral shows that take place in conference spaces, tents, hotel rooms, and parking lots across the city. This year a number of exhibitors noted the lack of Chinese buyers, who are now likely to make their purchases at the Hong Kong show for convenience. For many exhibitors, however, Tucson remains a very important venue in the year’s trade show calendar.

For Alexander Wild (Wild & Petsch Lapidaries, Kirschweiler, Germany), the show was a place to write invoices and do “serious selling.” While many clients were not shopping for any one particular gem, they were seeking out unique items: fine-quality gems as single pieces, matched pairs, sets, or suites. Exhibitors selling everything from cultured pearls to unheated tanzanite, Australian chrysoprase, and top-quality ruby, sapphire, and emerald echoed the same sentiment: fine goods were strong sellers.

Wild attributed the current shortage of gem rough to the global economic crisis that began in September 2008. The following years, he recalled, were “disastrous” for many in the colored gem trade, as their customers simply stopped buying. The resulting lack of liquidity cascaded down to active mining operations, especially in Africa and Brazil. Miners in those areas were left with no clients for their previously mined goods, and no income with which to purchase equipment or staples such as diesel fuel. Within a short time, Wild said, many operations were saddled with debt and subsequently ceased operations. Mine workers returned to the agricultural sector, which began to rebound in 2009. By then, costs had become so prohibitive that many former operators could no longer afford to return to the mining industry.

	Hans Juergen AlthoeferEmil Kreis & Co.

Hans Juergen Althoefer of Emil Kreis and Co., explains how changes in the colored stone market are reflected in the stock his company carries. While business was formerly concentrated on smaller calibrated goods, clients now demand more unique ‘one-of-a-kind’ pieces along with matched pairs and sets.
One common refrain among exhibitors was the intense competition for scarce cutting rough, creating a dramatic price increase. Many mentioned stiff competition from Chinese buyers or their agents at the sources. Steve Ulatowski of New Era Gems (Grass Valley, California) told us the price of pink to red tourmaline rough has shot up due to Chinese demand. He cited Nigerian tourmaline rough that was priced at $8,000 per kilogram several years ago; the current asking price for equivalent goods was $200,000 per kilo, with sellers asking for cash on the table.

Many dealers also emphasized the importance of “recirculated” gems or jewelry pieces, remarking on the high quality of pieces in the secondary market. These included fine sapphire, ruby, alexandrite, and cat’s-eye chrysoberyl, gems that were otherwise unobtainable. All find a ready market in Asia.

Regardless of these powerful undercurrents, most of the exhibitors who spoke with us expressed satisfaction with their results from Tucson. Although traffic at some shows was down from previous years, exhibitors reported that buyers were serious and business was satisfyingly brisk.

All in all, the Tucson gem and mineral shows are a fascinating cross section of materials, sellers, and buyers that provides a unique window into a singular industry. We eagerly look forward to next year’s shows.

G&G appreciates the assistance of the many friends who shared material and information with us this year, with special thanks to the American Gem Trade Association for providing photography studio space during the AGTA show. GIA’s Eric Welch, Pedro Padua, Clara Zink, and Andy Lucas contributed to this report. Source: GIA @topic:7


Title: More of the Interesting and Unusual – Tucson 2014 Abstract: Figure 1. This emerald crystal, reportedly from Muzo, Colombia, is approximately 35 mm long and contains an eye-visible multi-phase inclusion. The gas bubble within the inclusion moves a few millimeters as the crystal is tilted. Photo by Duncan Pay, courtesy of William Johnson, Natural Formations.

Some of the most captivating Tucson exhibits were among the hardest to categorize, although many could be described as phenomenal. From asterism and opalescence to bold and bright patterns, Tucson attendees encountered an abundance of fascinating and unique finds this year.

	Gary SommerConsilio Designs, LLC

The array of bright colors seen in Taiwanese “seven-color jade” comes from serpentine and actinolite within the stone.
Gary Sommer of Consilio Designs, purveyor of “seven-color jade” out of Taiwan, says that each of his decorative pieces is different, and customers tend to get overwhelmed because they like every one they see. The tough and glossy pieces, from vases to tables, are splashed with bright color, a look Sommer says is caused by serpentine and actinolite in the mix. The one-of-a-kind items are manufactured in Taipei.

	Dmitriy BelakovskiyExotic Minerals of Russia

Key concepts of synthetic quartz growth include an understanding of crystallography and the use of seed crystals in an autoclave.
Trace elements like iron and cobalt, combined with high pressure and high temperature in an autoclave, produce brand-new crystals in vivid colors from Dmitriy Belakovskiy’s Exotic Minerals of Russia. The New Jersey company grows synthetic crystals from natural rough that are both beautiful and useful.

Belakovskiy is curator of the Fersman Mineralogical Museum in Moscow; Exotic Minerals of Russia, his side business, sells Russia-grown synthetic quartz, synthetic diamonds, and synthetic moissanite. His most interesting specimens show the result of synthetic quartz growth on natural quartzite: The regeneration of broken natural quartz crystals with synthetic tips produces a result that bears a strong resemblance to natural quartz.

However, Belakovskiy emphasizes that synthetic quartz can be distinguished from natural by its lack of horizontal striations perpendicular to the c-axis. These striations are always present in natural quartz.

In addition to sharing his unique creations and their genesis, Belakovskiy sheds light on the relationship of the seed plate used to initiate and control growth and the finished synthetic crystal. According to Belakovskiy, natural quartz seeds produce clear synthetic crystals with fewer defects.

	Jim BushnellPyramid Peaks Gems

A lapidary reveals how to spot star and cat’s-eye effects in rose quartz rough and orient the material to best display these phenomena.
Colorado Springs company Pyramid Peaks Gems brings asteriated rose quartz to market, which conceals its winking stars and eyes within cloudy rough. Cutting to reveal the hidden phenomenon to its best advantage takes a lot of practice, according to owner Jim Bushnell.

	Artur F. Silva Jr.AFS Gems

Through a combination of heat and irradiation, a Brazilian company is producing treated quartz with “kunzite” or “strawberry” colors that are completely stable.
Out of Minas Gerais, Brazil, come two types of treated quartz offered by Artur F. Silva Jr. of AFS Gems. A heated, irradiated quartz in a lilac hue reminiscent of kunzite holds its color well and shows either a milky quality or an opalescent effect when polished. Silva’s “strawberry” quartz of mottled pink and white is heat treated only, and at first blush looks nothing like the plain brownish-gray material it once was.

	Paul CoryITECO, Inc.

An initiative to raise market awareness of certified untreated U.S. gemstones such as turquoise from a mine near Kingman, Arizona, and benitoite from a single source in California.
Paul Cory of Iteco has the blues—from rare sky-blue turquoise specimens to all shades of blue benitoite, faceted and sparkling with dispersion. Find out how his Mountain Certified program informs consumers and learn more about a unique, rare gem whose supply is fast waning.

Benitoite is the true California gem; the mineral occurs only in the Golden State in only one mine in the world. According to Cory, benitoite’s high dispersion and refractive index make its lively blues more akin to diamond than to sapphire. Cory’s connection with benitoite began in 2001, when an associate of his asked him to find a use for the broken crystals associated with mining benitoite; over five years, Cory accumulated a considerable amount of rough benitoite suitable for cutting faceted stones, which he now offers for sale.

According to Cory, because the only commercial benitoite mine is now shuttered, except to collectors, the unique gem is becoming scarce indeed: “When it’s gone, it’s gone!” he asserts.

Cory’s enthusiasm for the blues extends to rare turquoise for collectors, in colors ranging from green to light blue to dark blue, from the Kingman mine in Arizona. The specimens, produced from botryoidal growth around a small quartz nucleus, have received no stabilization treatment.

Cory plays a central role in developing a stronger market awareness for gemstones originating in the United States, as well as for the value of untreated gemstones. To that end, he has initiated a program, “Mountain Certified,” for designating gems from the United States that are untreated and in whose mining he has been personally involved.

Figure 2. This spectacular 7,043 ct turquoise nugget was recovered from the Lavender Pit mine of Arizona in 1934. Lavender Pit was adjacent to the much larger Bisbee copper mine. Much of the turquoise from Arizona’s mines was reputedly smuggled out by copper miners, and thus referred to as “lunch bucket” turquoise. Photo by Eric Welch, courtesy of Studio GL.

Figure 3. These curious examples of “crazy quartz” are reportedly from basalt cavities in the Gobobos Mountains of Namibia. These well-formed colorless quartz crystals are capped by smaller amethyst-colored tips in a “reverse scepter” formation. The crystal cluster is approximately 6 cm wide. Photo by Eric Welch, courtesy of Stefan Reif, Reif Collection.

Figure 4. These slices of liddicoatite tourmaline display colorful growth zoning. The largest slice measures approximately 30 cm. Photo by Duncan Pay; courtesy of Frederic Gautier, Little Big Stone.
Among the other fascinating materials seen in Tucson were a Colombian emerald crystal with an eye-visible multi-phase inclusion (figure 1), a large nugget of turquoise (figure 2), some interesting quartz from Namibia (figure 3), and large colorful slices of liddicoatite tourmaline (figure 4). Source: GIA @topic:1


Title: Dona Dirlam Abstract: Dona Dirlam’s playthings of choice growing up in Minnesota were a collection of Oregon agates. Pursuing this hobby led to a master’s degree in geology and geophysics and a position as a geology and earth science teacher in Madison, Wisconsin. Yet her interest in gems never wavered, and when she heard about GIA’s degree programs, she moved to Santa Monica to pursue her GG. Thus began a lifelong affiliation between Dirlam and GIA that has changed the face of the Institute’s library and research resources.

Upon completion of her GG in 1979, Dirlam was encouraged by Dr. Vincent Manson to work as a diamond grader until a position in research became available. While she waited, she made such use of the Institute’s library that she caught the attention of Richard Liddicoat, who was seeking someone with a background in gemology, geology and teaching to revamp the Institute’s library. He found a willing and able candidate in Dirlam, who assumed her new responsibilities as GIA’s librarian in July 1980. Since December 1995, she has been director of the Richard T. Liddicoat Gemological Library and Information Center, which under her leadership became the world’s largest and most prestigious library of its kind.

Among Dirlam’s successes during her tenure with the Institute were the 1987 acquisition of the 14,000-volume John & Marjorie Sinkankas Gemological Library, a negotiation that took four years to complete. She tirelessly lectured on gemological subjects and served as abstracts editor of Gems & Gemology from 1981 to 1994. She also serves as the secretary of the Geo-Literary Society. To date, Dirlam has also coauthored 11 articles for the journal, five of which received a G&G Most Valuable Article award. Her contributions to both GIA and the field of gemology led to widespread accolades, including the 1989 Outstanding Gemologist Award from the Association of Women Gemologists and GIA’s Staff of the Year in 1991. GIA selected her for its highest honor, the Richard T. Liddicoat Distinguished Achievement Award, in 2004.

Under Dirlam’s 34-year leadership, the library has expanded from a 2,000-book installation to a state-of-the-art facility. Over 16,000 books and 1,800 videos are in circulation, along with CD-ROMs, audio CDs, and subscriptions to over 230 periodicals in numerous languages, with access provided to students, staff, and the general public. The Cartier Archives and Rare Book Repository Collections, which houses the Sinkankas collection, has expanded from an initial 14,000 books to 41,000 resources. The Visual Resources Library, also maintained by the Carlsbad library, contains over 143,000 images and assets to enhance the Institute’s course and publication materials. Dona Dirlam’s groundbreaking efforts on behalf of the Institute’s research, education, and outreach capabilities have kept GIA at the forefront of gemological scholarship. Source: GIA @topic:7


Title: Large Faceted Afghanite Abstract: An exceptionally large and clean 1.91 ct faceted oval brilliant afghanite was recently submitted to GIA’s Carlsbad lab. Photo by Robison McMurtry.

Afghanite is a blue mineral named in 1968 after its discovery in Badakhshan Province, Afghanistan. It is often found in association with lapis lazuli and sodalite (R.V. Gaines et al., Dana’s New Mineralogy, John Wiley & Sons, New York, 1997, p. 1634). It has a chemical formula of (Na,Ca,K)8(Si,Al)12O24(SO4,Cl,CO3)3·H2O (Gaines et al., 1997). Since 2003, there have been only a few mentions in the literature of gem-quality afghanite (Winter 2003 GNI, pp. 326–327; Spring 2008 GNI, pp. 79–80; Fall 2011 GNI, p. 235; Spring 2015 GNI, p. 83), with no reports of finished faceted stones larger than 1.5 ct. Five gem-quality samples ranging in size from 2.87 to 7.25 ct have been reported; however, all five were cabochons and contained numerous inclusions of lazurite (Winter 2003 GNI, pp. 326–327).
For these reasons, the 1.91 ct transparent faceted oval brilliant afghanite recently submitted to the Carlsbad lab for an identification report was truly exceptional (see above). The only inclusions in the stone were minor fractures. To date, it is the largest facet-grade afghanite on record in the GIA gem identification department. Standard gemological testing revealed that the stone was doubly refractive and uniaxial, with a refractive index (RI) of 1.522 to 1.530 and a specific gravity (SG) of 2.52. These results are consistent with the published properties of afghanite (Gaines et al., 1997). Additionally, an early report on gem-quality afghanite notes that “an interesting feature of afghanite that should prove useful in its identification is its strong, bright orange fluorescence to long-wave UV radiation,” a property that this remarkable stone exhibited (Winter 2003 GNI, p. 326–327). Further confirmation of the stone’s identity was obtained by using Raman spectroscopy, which yielded a spectrum that matched that of known afghanite samples. Source: GIA @topic:2


Title: Celebrating 50 Years of Tsavorite Abstract: Figure 1. A selection from Campbell Bridges’s tsavorite collection, displayed at the 2017 AGTA Tucson Gem Fair. This collection includes some of the most important pieces found in the past half century. Photo by Robert Weldon/GIA, courtesy of the Bridges family.

The year 2017 marked the 50th anniversary of Campbell Bridges’s discovery of tsavorite. At the 2017 AGTA Tucson Gem Fair, the Smithsonian Institution hosted a selection of historical pieces from Bridges’s personal collection to commemorate his life’s work (figure 1).

Starting in the front row and proceeding from left to right, we begin with two crystals that are some of the first tsavorites Bridges discovered, near Komolo, Tanzania, in 1967. These are among the first samples that were analyzed to identify this new gemstone.

Next, the tsavorite in matrix represents the 1970 discovery in Taita, Kenya, at Bridges’s GG3 mine. Also represented from this location is a lovely tsavorite “thumbnail” unearthed in 1971. Some years prior, Bridges was engaged by Tiffany & Co. as a consultant. He was the first to bring tanzanite to the United States, and was credited with the discovery of tsavorite in Tiffany ads introducing the gem to the public in 1974 (figure 2).

Figure 2. In this 1973 photo, Campbell Bridges (right) discusses tsavorite with Henry B. Platt, former president of Tiffany & Co. Photo courtesy of the Bridges family.
The three large tsavorite rough samples weighing more than 5 grams each were found in 1980 at a source Bridges christened the Scorpion mine. The vibrant yet rich pure green to bluish green hue became a well-known characteristic of material from this mine. Over the following four decades, the Scorpion mine would prove to be the world’s most prolific producer of fine tsavorite.

The next six rough pieces, weighing 5 to 25 grams, were recovered in 1992 from the famed Bonanza tunnel at the Scorpion mine. The Bonanza tunnel is the richest tsavorite-bearing reef zone at Scorpion and has yielded some of the finest pockets the world has seen. The “saddle reef structure,” a series of recumbent folds, is the characteristic geological feature identified by Bridges at the Scorpion mine. This distinctive structure has led to the mine’s rich and consistent production throughout its history.

Rounding out the Scorpion mine material in the top left corner is an extremely rare terminated euhedral tsavorite crystal in matrix. As tsavorite occurs under very high pressures and temperatures, it is often highly fractured in rough form, making such an unblemished and well-formed specimen a remarkable occurrence.

In the top right corner, we have a tsavorite nodule in matrix that opens a window into the gem’s formation and its associated minerals. This nodule was extracted in its entirety from the Bonanza reef three decades ago and kept intact.

On display (again, see figure 1) are tsavorite, surrounded in the matrix by tanzanite, calcite, pyrite, quartz, and graphite. Tsavorite and tanzanite can occasionally occur together, though their formation is separated by approximately 100 million years. Tsavorite forms under prograde metamorphism and tanzanite under retrograde metamorphism.

Keeping guard on this tsavorite bounty are the namesakes of the Scorpion mine. These pewter scorpions were directly cast from actual scorpions that patrolled the mine. Needless to say, it’s advisable to check your shoes in the morning… Also on display is one of Campbell Bridges’s earliest business cards, from 1967.

In the top row are four extraordinarily fine, loupe-clean faceted gemstones. None of these were ever on public display before the Tucson exhibit. The first is a lovely 25.10 ct “mint” green grossular garnet, unearthed in 1971 from Bridges’s GG2 mine in Taita, Kenya. Interestingly, this color of mint green garnet has been found at all of the Bridges mines in Tanzania and Kenya over the decades. A strike may yield both richly colored high-chromium and vanadium-colored saturated tsavorite, as well as the far lighter, mint green garnet within the same pocket. This variety is most prevalent in Merelani, Tanzania, but also occurs near Komolo, Tanzania, as well as in Taita. While such material came from all three locations in the early years, it simply was not marketable back then. It was not until the 2000s that a real market for these garnets developed.

Next is an exceptional 31.27 ct oval from Merelani with a vivid blue-green color. This tsavorite retains fantastic brilliance even in low lighting, while maintaining a sufficient level of saturation under strong lighting.

Last but certainly not least are two tsavorite cushions. As to their origin, the Bridges family wishes to preserve an element of mystery. The 33.55 ct square cushion on the right is a loupe-clean gem exhibiting an exceptional blue-green color that is well saturated yet extraordinarily vivid. After a lifetime of dealing with tsavorite, the author considers this one of the finest examples ever produced between 10 and 50 carats.

The largest of the four faceted gemstones in this display is a 58.52 ct cushion. It is another loupe-clean example representing the pinnacle of what is possible in tsavorite. It also exhibits a strong blue-green color that glows in any lighting environment. This is the finest tsavorite above 50 ct observed by this author. Given its one-of-a-kind nature, the Bridges family felt it most appropriate to name the gem the “Golden Jubilee” in honor of tsavorite’s 50th anniversary.

As tsavorite and the legacy of Campbell Bridges celebrate 50 years, the Bridges family wishes to thank the Smithsonian and the colored gemstone community for their support throughout the years. Source: GIA @topic:1


Title: 30-Year Marine Corps Veteran Fulfills Dream of Becoming a Field Gemologist Abstract: Retired Master Gunnery Sergeant Manuel Diaz, GG, has found that his extensive experience in “jungle environments around the world” prepared him well for the rigors of field gemology. Here, Diaz traverses jungle-covered kharsts while climbing the Cung Truoi spinel mining cliff in Vietnam. Diaz, an independent gemologist, joined GIA's team from Bangkok on a field expedition there in the spring of 2015. Photo by Vincent Pardieu/GIA

Editor's Note: This article was originally published on Nov. 28, 2016 and has been updated.

Whether exploring jungles in Madagascar or riverbeds in San Diego County, Manuel “Manny” Diaz likes to say he’s “living the dream.”

And what a dream it is: after retiring from the United States Marine Corps with more than three decades of service and 20 deployments, Diaz finally pursued his decades-long goal of earning a Graduate Gemologist diploma from GIA and began to work as an independent field gemologist.

For Diaz, the gem and jewelry trade is no mere industry, but a family that embraced and mentored him as an 18-year-old Marine.

“On my first overseas assignment, I was on ‘R&R’ and was introduced to a gem broker who worked with Australian opals,” Diaz says. “He was friendly and open to questions and gave me my first introduction to the ‘mine to market’ concept – then he introduced me to many others along that journey. I was befriended worldwide by brokers, miners, cutters, jewelers − even pearl divers for the Bahrain royal pearl beds.”

Manuel Diaz, third from left in the back row, served 20 deployments over three decades in the United States Marine Corps. Diaz, who earned his GIA Graduate Gemologist diploma immediately after his 2014 retirement from the Marine Corps, is pictured here on his final deployment, to Afghanistan. Courtesy of Manuel Diaz
The more Diaz traveled with the military, the more he met like-minded gem enthusiasts. In 1987, while stationed in the Philippines, he began to research how he could gain a formal education in gems and minerals.

“I came across GIA in a reference book, and promised myself that I would attend any and all courses they offered when I completed my Marine duties,” he says.

As Diaz gained a working knowledge of gems, minerals and the supply chain, his information proved useful for military operations. On one combat deployment, Diaz was required to investigate and advise how Marines might reduce conflict at a nearby marble quarry. Hostile forces there were taking over the deposits, stealing income and trade revenue from the rightful owners.

“Some personnel immediately recommended air and artillery bombardment to the quarry,” Diaz says. “But having an experienced knowledge of mining operations, I quelled those ideas for a more tactical approach. The quarry began operations that soon deterred the hostiles and kept them from taking advantage of the deposits. It reduced the income base for hostile forces and increased revenue for the indigenous people.”

Diaz also found that his fellow Marines wanted to tag along on his exploratory trips during their “R&R” breaks.

“There were times I would take 10-20 people on a trip and teach them about gems and participate in their personal trades,” he says.

Manuel Diaz, addressing the crowd at his 2014 retirement ceremony at the Marine Corps Base Camp Pendleton, says that no one in his family was surprised at his career change. He spent his off-time on international deployments exploring and learning about the local gem and jewelry industry. Courtesy of Manuel Diaz
Diaz was able to pursue his dream in 2014 when he retired as a Master Gunnery Sgt. from the First Marine Expeditionary Force at Marine Corps Base Camp Pendleton – just a 20-minute drive from GIA’s World Headquarters in Carlsbad. He used the G.I. Bill to begin his studies online and on campus immediately and by the end of the year, earned his AJP, Graduate Pearls and Graduate Gemologist diplomas.

As a student, Diaz attended a lecture by former GIA field gemologist Vincent Pardieu, and approached him to talk afterward. Soon after, Diaz was on his first expedition as an independent field gemologist, traveling along with a GIA team to Vietnam. It turned out that Diaz – who had extensive experience in expeditionary engineering, international security, emergency response management and military special operations (including serving the U.S. Department of State as a Security Guard Detachment Commander for consulates and embassies in Athens, Greece and Addis Ababa, Ethiopia) – was well-equipped to handle the rigors and often-harrowing conditions of field expeditions.

“I had 30 years to hone my skills in packing and personal equipment preparation for long durations,” he says. “Nowhere else could a person gain the experience and knowledge given a Marine going through deployment preparation and execution. Our thought process is different – foreign for someone who has not had to survive a life-altering experience.

“It’s not that there are no new experiences for me, but I travel prepared, regardless of location and time on deck,” says Diaz, who is also certified as a master scuba diver. “With the ‘ruby rush’ expedition to Madagascar, for example, I was familiar with the conditions – it wasn’t the first time I visited Madagascar – and I have a huge amount of experience in jungle environments around the world.

“Know yourself and seek self-improvement – no one is going to do it for you,” says field gemologist Manuel Diaz, pictured in a morning gem market at Yên Thế, Lục Yên, Yên Bái, Vietnam. After a three-decade career in the military, Diaz followed a longtime dream to join the gem and jewelry industry. Photo by Vincent Pardieu/GIA
That preparedness − and not being unsettled by harsh terrain, aggressive people or even life-threatening experiences that could rattle those less-experienced – make it possible for Diaz to focus on the people involved.

“As a Marine, you find that it’s all about those people who are with and around you,” he says. “For me, the experience in field gemology is about the people I come in contact with. Finding the gem is key, but finding it with those around you – that’s the reason for me being there.”

The last year has been full and varied for Diaz, from working in Mozambique and conducting market research for a private mining company to teaching junior and senior high school students about the geological development of minerals.

Diaz, who lives in north San Diego County with his family and volunteers as a docent for the Fallbrook Gem and Mineral Society, also enjoys helping individuals hunt for gems close to home.

“If a family wants a particular quartz variety, a collector wants to explore a show or market, or a young couple wants a lesson on gem and jewelry purchases, I’m their guy,” he says. “Nothing is more important than tending to the needs and passions of my clients.”

Diaz says his time at GIA – and the “dedicated” faculty and staff members who became like extended family to him – opened the doors to professional dreams that were decades in the making. He is also trying to help other veterans find what lies ahead for them after the military by encouraging them to consider the gem and jewelry industry.

“I’ve lured a few of them to GIA,” he says. “Using the G.I. Bill for my GIA education was a great resource and a comfort for me – that is priceless.”

Manuel Diaz, here studying a blue spinel in Vietnam, says his GIA training equipped him to communicate with clients. “Being able to describe color in such a clear manner is helpful for not only grading, but in being able to explain it to clients looking for a particular hue or saturation in a gem,” he says. Photo by Lucie Martinez/GIA
One of those veterans is Diaz’s brother, Ramon – also a 30-year veteran of the Marine Corps and a retired Master Gunnery Sergeant. Ramon Diaz graduated in 2015 with a Graduate Jeweler diploma and in 2016 with a Jewelry Design and Technology diploma from the Institute.

The brothers are mulling how they might work together in the future, whether that is in the field or helping people learn about and buy gems. But Diaz knows one thing for sure.

“I’m in this for the find,” he says. “Not money, not fame. Simply the find.” Source: GIA @topic:7


Title: Opal from the Shewa Province, Ethiopia Abstract: Opal occurs as nodules in volcanic rocks at a new gem opal locality in the Menz Gishe district of Shewa Province, Ethiopia. The opal field, still in the early stages of exploration, extends over several square kilometers. Opals from Shewa Province have near-colorless to white, yellow, orange, gray, or brown body colors; some show face-up play-of-color, and many have contra luz play-of-color. The gemological properties are consistent with those of other natural opals, and small particles are common inclusions. Preliminary stability tests indicate that much of the material absorbs water and some crazes when exposed to light and heat. Source: GIA @topic:12


Title: Pyrope Garnet and Montana Sapphires Highlight Winter 2015 G&G Abstract: The lead article in this issue analyzes the color-change phenomenon displayed by a pink pyrope garnet believed to be of Tanzanian origin. The cover photo shows two pieces of pyrope garnet from Morogoro, Tanzania, that exhibit the reported color-change characteristics. The round “Super Spiral cut” specimen, weighing 15.25 ct., comes from the same material as the 42.42 ct. rough nodule. Photo by Robert Weldon/GIA, courtesy of Meg Berry

The Winter 2015 issue of Gems & Gemology offers in-depth analysis of pink pyrope garnet and alluvial Montana sapphires, a new look at a legendary sapphire once owned by Louis XIV, a study of tarnish spots in high-purity gold, and a visit to Australia’s historic opal fields.
Vanadium- and Chromium-Bearing Pink Pyrope Garnet: Characterization and Quantitative Colorimetric Analysis
A new type of pyrope, which shows a noticeable color change from purplish pink under incandescent light to purple in daylight, contains vanadium and chromium and is believed to originate in Tanzania.

GIA researchers Ziyin Sun, Dr. Aaron Palke, and Nathan Renfro performed extensive colorimetric tests on samples to analyze the color change and the factors that influence it.

They determined the range of stone sizes that maximize the color change, although the difference is not significant enough, according to some definitions, to be classified as an actual “color change.”
Alluvial Sapphires from Montana: Inclusions, Geochemistry, and Indications of a Metasomatic Origin
Alluvial sapphires have been mined for more than a century in Montana, but the original source rocks for this material have never been located.

A team of researchers led by Dr. J.C. “Hanco” Zwaan, head of the Netherlands Gemmological Laboratory and a researcher at the Naturalis Biodiversity Center, examined inclusions in sapphires taken from the Rock Creek area to determine their possible origin. Analysis of approximately 400 samples indicated a metasomatic origin. One specimen contained a topaz crystal, the first documented topaz inclusion in sapphire.

Montana sapphires occur at three commercial secondary deposits: Rock Creek, Dry Cottonwood Creek and the Missouri River area. These rough and faceted Rock Creek stones show the range of permanent colors after routine heat treatment without the addition of chemicals. The largest faceted gem weighs 0.43 ct., and the largest rough stone weighs 1.86 ct. Courtesy of Fine Gems International, Robert E. Kane
The Grand Sapphire of Louis XIV and the “Ruspoli” Sapphire: Historical and Gemological Discoveries
The 135.74 ct. Grand Sapphire, a legendary gemstone acquired by Louis XIV in 1669, is housed in the National Museum of Natural History (MNHN) in Paris. Newly discovered documents about this six-sided “lozenge”-cut sapphire indicate that the king acquired the gemstone about the same time he obtained the Tavernier Blue diamond, and that he had both mounted into gold settings in 1672. The Grand Sapphire has often been mistakenly referred to as the “Ruspoli” sapphire, a completely different gem, and archival evidence reveals the story of this confusion.

The authors, led by Dr. François Farges, professor of mineralogy at the MNHN, also determined that the sapphire likely originated in Sri Lanka.
Characterization of Tarnish Spots in Chinese High-Purity Gold Jewelry
Part of gold’s appeal is that it generally does not tarnish − but there have been instances where red, brown, or black tarnish spots have appeared on jewelry pieces of extremely high purity (99.9% Au). A team of Chinese researchers, headed by Dr. Taijin Lu of the National Gems & Jewellery Technology Administrative Center (NGTC) in Beijing, determined that the spots were caused by silver deposited on the gold surface during the manufacturing process.
Splendor in the Outback: A Visit to Australia’s Opal Fields
A GIA field report from the opal mines of Australia rounds out the feature articles in this issue. Australia exports more than $85 million worth of opals annually, with some 200,000 tourists visiting the opal areas each year.
Lab Notes
In the Lab Notes column, two of the largest CVD synthetic diamonds ever submitted to GIA’s lab demonstrate the continual improvement in quality and size of this material. In addition, there are reports on a treated pink diamond with a growth structure usually associated with HPHT synthetics and large natural fossil blister pearls from giant clams found in southeastern Kenya.

The I-color 3.23 ct. round on the left and H-color 2.51 ct. round on the right are the largest CVD synthetic diamonds GIA has tested. Photo by GIA
Micro-World
The Micro-World section presents photomicrographs of a Mexican fire agate cabochon whose coloration and structure creates an unusual visual effect, a red heart-shaped pyrope garnet inclusion in a round brilliant diamond, a violetish blue spinel inclusion in a yellow sapphire, parasite inclusions in Colombian quartz, and four-ray stars in Paraíba tourmaline.

Upon close examination with a field of view of 8.12 millimeters, the polished botryoidal knob in this Mexican fire agate resembles a reptilian eye. Photomicrograph by John Koivula/GIA
Gem News International
Gem News International reports on a large fluid inclusion in a demantoid garnet from Madagascar that provides a strong clue into the source’s mineralization. Other entries include a possible new source of grandidierite in Madagascar; a bluish green chalcedony from Africa, marketed as “Aquaprase;” and a report on ruby mining in Zahamena National Park in Madagascar. Source: GIA @topic:1


Title: Integrating G&G with GIA’s Gemology Education Abstract: One of the things I’ve always wanted to do is create synergy between GIA’s gemology courses and Gems & Gemology. Many of the student assignments incorporate research from the journal, and adding G&G articles as references would provide support and validation for the information in our coursework.

As we added video media to our eLearning courses, we featured interviews with many of GIA’s research scientists, some of whom were also G&G authors. Providing their articles to our students was a natural next step.

In the past, I had discussed this idea with Alice Keller when she was editor-in-chief of G&G. Although everyone was willing, we had no practical way to achieve it at the time. Now that every issue is available free of charge on the redesigned GIA website at www.gia.edu, we can realize this ambition.

Beginning with our Diamonds & Diamond Grading eLearning course, we’ll provide links at the end of every assignment to specially chosen G&G feature articles.

Besides illuminating some of the source material for our coursework, links to supporting articles will provide a truly meaningful pathway into the resources on our new website. Students with inquiring minds will find many avenues of interest.

For example, I believe a good number of students would choose to explore the important G&G articles on colored diamond, diamond treatment, or diamond synthesis. Others might also download articles focused on mining, production, and the diamond supply chain, or read about the many famous gems examined or graded by GIA’s laboratory.

This tie-in exposes the tremendous amount of important work that G&G authors—both internal and external to GIA—have done to enrich our collective knowledge on the many aspects of diamond, and makes it available to a wider, and younger, audience.

We’ll also provide a short student study guide that explains the structure of a typical feature article and explains how to navigate one. In time, we’ll add similar links to relevant G&G articles in our other gemology courses.

Let me take this opportunity to thank all our current G&G print subscribers and online users. I hope to welcome many more of you in the near future.

Duncan Pay  |  Editor-in-Chief Source: GIA @topic:7


Title: Supporting the Researchers of Tomorrow Abstract: In our recent print issues, you’ve likely noticed an ad on the journal’s inside cover promoting postdoctoral research opportunities. This is part of a GIA initiative to attract new research scientists. We recognize that sustaining future research is fundamental to all of GIA’s core gemological laboratory and education services that support the industry and our mission to safeguard consumers.

As part of this effort, we’re delighted to announce that GIA will be the principal sponsor of the International Diamond School (IDS), to be held January 27–31 in Brixen, Italy. The school will be led by three leading diamond geoscientists: Fabrizio Nestola of the University of Padova, Italy; Steven Shirey of the Carnegie Institution in Washington, DC; and Graham Pearson of the University of Alberta, Canada. The school brings together leading academics and practicing members of the diamond geoscience community—including our own Dr. Wuyi Wang—with the next generation of postdoctoral and masters-level researchers. It’s a fantastic opportunity for attendees to network with the leaders in diamond exploration, advanced research-level analysis, diamond morphology, inclusion chemistry, and geologic occurrences in a way that will inspire their future studies. GIA’s contribution will directly benefit these up-and-coming research scientists by reducing the attendance fees for the conference. The IDS website is at http://www.indimedea.eu/diamond_school_2015.htm

Our lead article in this edition, a collaboration between GIA and Sri Lankan authors, presents an illuminating survey of Sri Lanka’s gem and jewelry industry based on firsthand visits to mining, cutting, jewelry manufacturing, and retail centers. They document a revitalized industry that’s blending hard-won traditional skills with innovative strategies and technologies to gain a stronger presence in global markets.

Our second paper, by Nicholas Sturman and his colleagues from GIA’s Bangkok laboratory, provides a gemological characterization of 22 non-nacreous pen pearls. This study reveals not only the porcelaneous nature of these pearls, but also the unusual beauty of their surface textures and inner structures.

Next, noted author and corundum expert Richard Hughes delves into a basic gemological property: pleochroism. His intriguing paper—aimed at practicing gemologists as much as researchers—examines this property’s impact on the appearance of faceted gems and looks to demonstrate that pleochroism is always visible to some degree, even when viewing a gem along an optic axis.

In the final article, Dr. Zuowei Yin from the China University of Geosciences in Wuhan heads a study of pale-colored nephrite jade from a new deposit in Guangxi Province with interesting banded or dendritic patterns.

In addition to the four feature articles, you’ll find our regular Lab Notes and Gem News International sections, along with the winners of the 2014 G&G Challenge.

For all our print subscribers: You’ll notice that your copy of journal was delivered inside a new recyclable (polyhydroxyalkanoate, or PLA) wrapper. We’d like to thank Dr. George Rossman of G&G’s editorial review board for this suggestion.

Please enjoy the Fall 2014 edition! Source: GIA @topic:7


Title: Beryllium Diffusion of Ruby and Sapphire Abstract: Over the past two years, the heat treatment of corundum involving lattice diffusion of beryllium (Be) at temperatures over 1800°C has become a major issue in the gem trade. Although initially only orange to orangy pink (“padparadscha”-like) sapphires were seen, it is now known that a full range of corundum colors, including yellow and blue as well as ruby, have been produced or altered by this treatment. An extension of the current understanding of the causes of color in corundum is presented to help explain the color modifications induced by Be diffusion. Empirical support is provided by Be diffusion experiments conducted on corundum from various geographic sources. Examination of hundreds of rough and faceted Be-diffused sapphires revealed that standard gemological testing will identify many of these treated corundums, although in some instances costly chemical analysis by mass spectrometry is required. Potential new methods are being investigated to provide additional identification aids, as major laboratories develop special nomenclature for describing this treatment.

	DATA DEPOSITORY

Table 1: Samples Used for Gemological Characterization
Table 2: Trace-Element Compositions of Be-Diffused and Natural-Color Corundum Determined Using SIMS (ppma)
	Submitted by Wuyi Wang
	Prepared by Gems & Gemology staff
	July 30, 2003

Table 3: Durability and Stability of the Treatment in Be Lattice Diffusion–Treated Orange to Pinkish Orange Sapphires
	Submitted by Robert E. Kane
	Prepared by Gems & Gemology staff
	July 30, 2003

Supplementary Bibliography on Corundum Diffusion
	Prepared by Gems & Gemology staff
	July 30, 2003 Source: GIA @topic:3


Title: A Visit to the Natural History Museum of Los Angeles County Abstract: The Gems of California pedestal in the F.C. Hixon Gem Vault serves as the centerpiece of the museum’s gem and mineral gallery. Photo by Duncan Pay/GIA, courtesy Gem & Mineral Department, Natural History Museum of Los Angeles County.

                      In 2014, a team from GIA visited the Natural History Museum of Los Angeles County (NHMLAC) to document its gem and mineral collection. It’s thought to be the second-largest such collection in the United States, behind the Smithsonian Institution in Washington, DC.

This report documents the museum’s remarkable reference collection as well as its active research programs. You’ll explore its Mineral Hall and get an insider’s view of its collections area, including the normally off-limits “goodie room” with its standout specimens. The museum’s expert curators will also explain their research into new minerals and the causes of diamond color.

Our group was guided by the Mineral Sciences staff: associate curator Eloïse Gaillou, collections manager Alyssa Morgan, and curator emeritus Anthony Kampf. All have advanced degrees in their fields. Eloïse has a master’s degree in geology and a Ph.D. in materials science. Alyssa has bachelor’s and master’s degrees in geological sciences. And Anthony’s Ph.D. is in mineralogy and crystallography.

The NHMLAC’s Mineral Sciences staff consists of associate curator Eloïse Gaillou, curator emeritus Anthony Kampf, and collections manager Alyssa Morgan. Photo by Duncan Pay/GIA, courtesy Gem & Mineral Department, Natural History Museum of Los Angeles County.

	Museum Origin and History
The site now occupied by the Natural History Museum was once known as Agricultural Park. Established in the 1870s, it is described by the museum’s website as “a lawless area with horse racing, gambling, and prostitution.” That all changed when the site was renamed Exposition Park in 1910 and construction of the museum began. The Los Angeles Museum of History, Science, and Art opened its doors on November 5, 1913. Its first mineral collection consisted of just five boxes of specimens—a donation from Los Angeles capitalist General Charles Forman.

The collection grew steadily through a series of small donations. Then, in 1920, a major donation came from the Los Angeles Chamber of Mines and Oil. The collection was rich in fine specimens of copper-bearing minerals from Bisbee, Arizona.

In 1946, the museum established Mineralogy and Geology as a separate department. In 1952, the Mineral Hall was installed in the museum’s original rotunda. A series of donations over the next decade from Los Angeles jeweler William E. Phillips initiated the gem collection.

Many important donations followed, and in 1959, the museum began a campaign to build its mineral and gem collections through both donations and purchases. The source of many of the purchases was Martin Ehrmann, an important dealer in museum-quality minerals. He also sold many specimens to museum supporters, who later donated them.

View Gallery

	The museum’s collection features crystal specimens from all over the world, with an emphasis on gems of California.
In 1971, the museum began construction on a new north wing to house its Hall of Gems and Minerals, which opened in 1978. The hall was enhanced by an important series of donations from San Antonio plutocrat Frederick C. Hixon, who donated his gem collection between 1971 and 1977, and from Jean Bandy, who donated a collection rich in Bolivian mineral specimens between 1977 and 1980. In 1985, the Ben Chromy mineral collection arrived, along with more than $100,000 for museum activities.

1985 marked the opening of additional gallery space known as the Deutsch Gallery: Gemstones and Their Origins. It was funded by Alex Deutsch, a pioneer in the aerospace industry, and by the Weingart Foundation. The gallery exhibits focused on explaining how gemstones form and where they are found.

Retired lawyer John Jago Trelawney donated his gem collection to the museum in 1988 and bequeathed around $450,000 to support research projects upon his death in 2001. In 2005, the exceptional Weber-Perloff collection was donated to the museum. Consisting of about 50,000 small specimens, called micromounts, it was one of the largest collections of its kind in the world. In 2010, NHMLAC received the extraordinary collection of Hyman and Beverly Savinar, which is especially rich in gem-quality crystals. In 2011, the museum received the collection of Mel and Lois Hindin, which consisted of many remarkable minerals and gems.

Today, the museum is a living, vibrant institution, filled with the chatter of schoolchildren as they press their noses against the display cases. But there’s much more to the museum than its public face. The off-display areas house one of the most significant mineral and gem collections in the United States.

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	Among its treasures, the museum boasts a dazzling collection of fashioned gems.

	An Overview
The museum’s gem and mineral collection consists of approximately 150,000 specimens representing about half of the world’s known mineral species. Of that number, there are about 143,000 minerals, 3,000 rocks (mineral aggregates), 3,000 gems, and 50 meteorites.

The specimens come from purchases, donations, and exchanges with other institutions. The museum has specimens from around the world, including the largest and most extensive collection of California gems and minerals.

There are more than 2,000 specimens on display in the 6,000-square-foot Gem and Mineral Hall. Yet this number is dwarfed by the total of specimens available behind the scenes for research or future display. One of the major storage areas is the Collections Room.

	The Collections Room
The vast majority of the museum’s mineral specimens are housed in the Collections Room. Most of them are not worthy of display, but they are invaluable to geologists and other scientists as research subjects.

As collections manager for the museum, Alyssa Morgan works among rows of mineral-filled cabinets, stacked almost floor to ceiling. Her job is to maintain the collection and the database and catalog.

Users of the collection—mostly geologists and material scientists in research institutions—can request specimens related to their studies of minerals from a certain area, or of rare or unusual minerals. Samples are broken off from larger specimens and mailed to the requesting parties.

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	The collections are carefully organized and catalogued to make searches easier.
The museum’s staff works to obtain rare or unusual items to make the collections complete. When a specimen comes in, it gets a catalog number. The number is glued to the mineral and recorded on the box it’s stored in for tracking purposes. The mineral is weighed and sometimes measured, and its information—source, how it was obtained, and other important details—is entered into the database.

Specimens in the Collections Room are organized into several sub-collections. The general reference minerals are arranged systematically by chemical class (elements, sulfides, oxides, etc.). California specimens are arranged by locality. Small micromounts and thumbnails are arranged alphabetically by species.

	Maintaining the Collection

	In this series of videos, Alyssa Morgan and Eloïse Gaillou discuss the mechanics of establishing and maintaining the main collection.

	Micromounts and Thumbnails
Micromounts and thumbnails are popular with an important segment of the mineral collecting world, and they are often excellent candidates for scientific research. Through large donations, especially the exceptional Weber-Perloff collection, the museum has amassed more than 100,000 micromounts—the largest such collection in the world. It includes many gold specimens, mostly from California, and more than 2,000 diamond crystals.

The thumbnail collection is also quite large, consisting of about 10,000 specimens that came mostly from a single donor, Jessie Hardman, in the year 2000. Because Mrs. Hardman was determined to have a piece of everything, the collection includes many rare minerals representing a variety of rarely represented localities.

Small plastic boxes provide some protection from the environment, humidity, and other factors. Although the specimens are small, they’re valuable because of their diversity. They also require little storage space and, because of their uniform sizes, are easily organized.

	Organizing by Size

	Minerals in the collection are organized in part by their size.
The micromounts and thumbnails come from sources around the world and are arranged alphabetically by location. The staff is working to catalog the entire micromount and thumbnail collections.

	The “Goodie Room”
The museum’s “goodie room” is the staging area for specimens in fine, unbroken condition. Of the approximately 4,500 mineral specimens and gemstones in this room, some are not quite worthy of display and some are simply duplicates of items already on display. Some have good enough color and transparency to be suitable for faceting. For the most part, these specimens are not available to researchers for sampling.

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	Some of the museum’s finest specimens not on display are stored in the goodie room.
Most of the goodie room’s collection comes from donors. One example is the extraordinary Savinar collection, which is full of fine-quality crystals from all over the world, along with many faceted gems.

	The Goodie Room

	Specimens in the museum’s goodie room are all fine quality. Most come from donors.

	Standout Specimens

	Anthony Kampf and Eloïse Gaillou introduce some of their favorite specimens and describe the characteristics that make them so special. Anthony then describes the museum’s acquisition process, which sometimes results in beautiful surprises.

	Researchers and Their Research
The core of any major natural history museum is the research that takes place behind the scenes. Current projects at NHMLAC include Anthony Kampf’s research into new minerals and Eloïse Gaillou’s studies on colored diamonds.

Curator emeritus Dr. Anthony (Tony) Kampf joined the museum in January 1977, and helped create the world-renowned Hall of Gems and Minerals. Tony played an important role in soliciting acquisitions and arranging the galleries. He has overseen the growth of the museum’s mineral and gem collection from about 20,000 to more than 150,000 specimens.

Dr. Kampf’s bulletin board is full of diagrams that show crystal structures of minerals he’s worked on. Photo by Duncan Pay/GIA, courtesy Gem & Mineral Department, Natural History Museum of Los Angeles County.
Now retired, he still comes in every day to engage in research that focuses on discovering and characterizing new minerals. He uses sophisticated instrumentation to identify minerals and study their internal structure.

	Research Projects

	In these videos, Drs. Kampf and Gaillou discuss their research projects on behalf of the museum.
Associate curator Dr. Eloïse Gaillou came to the museum in 2012 after holding a combined postdoctoral research fellowship with the Smithsonian and Carnegie Institutions. Eloïse’s work at NHMLAC focuses on diamonds, especially colored ones in the pink and purple ranges. Her goal is to determine the elusive cause of the pink color. Another of her research interests is the geology of diamond formation.

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	This slideshow takes you on a tour of the Gem and Mineral Hall, where the public can view a portion of the museum’s massive collection.
For more information about the museum and its mineral exhibits, visit the NHMLAC Mineral Sciences website at http://www.nhm.org/site/research-collections/mineral-sciences. Source: GIA @topic:7