Title: Olivine in Oregon Labradorite Abstract: Figure 1. This octagonal step-cut labradorite (left) was faceted with an extra-large girdle and a simple faceting pattern to showcase the olivine inclusion trapped inside (right). Photos by Kevin Schumacher.

	Gem-quality labradorite from Oregon is typically prized for its red, orange, and green colors, as well as the tiny exsolution platelets of copper that create the phenomenon of aventurescence. Other notable inclusions can also be found in this gemstone from time to time, such as the olivine inclusion in the stone provided by Ken Lack of Gem Net LLC in Grants Pass, Oregon (figure 1). These rare inclusions typically display a greenish yellow bodycolor and compression cracks, indicating a significant amount of strain between the feldspar host and the olivine guest (figure 2; see E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Vol. 2, Opinio Verlag, Basel, Switzerland, 2005, pp. 419, 422). In this example, the stone was reported to have cracked during cutting, presumably due to the strain. This labradorite was cut to showcase the inclusion, making it easy to view from multiple angles.

Figure 2. The olivine inclusion was photographed in an immersion liquid, which wicked along surface-reaching cracks and partially eliminated the reflective interface, allowing better observation inside the olivine. Photomicrograph by Nathan Renfro; field of view 3.83 mm.

	Olivine inclusions in labradorite feldspar typically indicate an Oregon origin—if one is lucky enough to find such a rare internal feature. Source: GIA @topic:2


Title: Ethical and Sustainable Vertical Integration in the Sapphire Market Abstract: Untreated yellow sapphires such as this 12.18 ct gem command a premium in the marketplace, especially when a transparent chain of custody and sustainable mining practices can be documented for the customer. Photo by Eric Welch/GIA, courtesy of Sheahan Stephen Sapphires.

	When the recession of 2008 struck, Sheahan Stephen (Sheahan Stephen Sapphires, Inc., San Francisco, California) had been dealing in Sri Lankan gemstones for two years. He saw his monthly cash flow drop to a third of what it had been when he first started traveling to Sri Lanka to buy stones for resale in the United States. During the recession he decided to borrow money and become vertically integrated. Stephen created a transparent supply chain and an ethical supply model by becoming directly involved in mining. His new business also included heat treatment, cutting, and sales.

	Sustainable practices tie directly into Stephen’s beliefs in how businesses should strive to operate. He sees lack of sustainability as a major cause of many of society’s problems. He works with his customers in what he calls “customized” vertical integration. He fills specific orders for his customers directly from mines and brings the sapphires to market in a controlled manner, meaning they are always in his hands or an employee’s hands until they reach the final customer. Stephen guarantees the entire supply chain and strives to provide full documentation, including the mine the sapphires (see above) came from and the name of the treater and the cutter.

	He focuses on education and training in Sri Lanka to obtain the quality and traceability his customers expect. Training and complete trust in his Sri Lankan staff allow him to buy stones unseen that will fill his customers’ specifications. Stephen also believes in providing education and other assistance for his employees’ families in Sri Lanka.

	Stephen finds that customers today want more information about their jewelry. They want to know where a piece came from, who was involved in manufacturing it and bringing it to market, and the corporate social responsibility practices of the company involved. With many of his customers today willing to pay 30% more for documented ethical sapphires and sapphire jewelry, he focuses on growing his sales with sustainability-minded clients. At the same time, he strives to be close to other wholesalers in his pricing to stay competitive and grow his business.

	A major part of his business investment is the time he spends growing relationships with miners and cutters in Sri Lanka that can take years. That is an essential element of developing a sustainable business model for artisanal mining. Stephen hopes that building long-term relationships with his employees and suppliers in Sri Lanka and perfecting the processes throughout the supply chain will allow for slow but sustainable business growth. His vision is to take this model to other gem mining countries, especially in Africa, where he is currently working in Madagascar. Source: GIA @topic:10


Title: An Inside Look at the 2017 Tucson Shows Abstract: A 59.28 ct quartz with iron staining. Photo by Robert Weldon/GIA, courtesy of Rare Earth Mining Co.

The 2017 Tucson gem and mineral shows drew eager buyers from all over the globe. Although many dealers reported lower traffic this year, most were content with the volume of business and noted that buyers were “serious.”

As in previous years, we identified some strong trends:

Demand for special one-of-a-kind pieces in both pearls and colored gemstones
Continuing investment by multinational companies in colored gemstone mining and distribution
A growing focus on ethically sourced gemstones and beneficiation
Strong demand for high-end gems and a softening of demand for commercial goods
Continuing importance of the secondary market in the U.S. for exceptional pieces
Innovative partnerships emerging between individual colored gemstone mines, designer cutters, and television merchandisers

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An Inside Look at the 2017 Tucson Shows
This year’s big story was the emergence of Ethiopia as a potentially major source of gem-quality emerald. These new gems resemble other schist-hosted emeralds, especially those from Brazil and Zambia. Although most of the material is less saturated and included, dealers are excited that the new source also produces fine gem-grade crystals of exceptional size, color, and clarity.

Dealers also talked about the October 2016 removal of U.S. sanctions on Myanmar, legalizing the import of Burmese jadeite and rubies. According to Edward Boehm of RareSource, the lifting of the ban was widely welcomed, but Myanmar government reforms of the gem mining sector have some way to go. Conditions on the ground are much improved, however. Boehm told us new production might take some time to appear, which would impact prices and selection of available goods in the short term.

Large multinational companies have significantly impacted colored gemstone mining and distribution over the last decade. Gemfields’ Kagem and Montepuez mines supply approximately one-third of global emerald and 70% of global ruby production, respectively. At this year’s show we were able to interview Gemfields CEO Ian Harebottle for his perspective on the company’s operations and its 2013 merger with luxury brand Fabergé.

Representing another publicly traded company intending to mine ruby in Mozambique, Christiaan Jordaan of Mustang Resources LLC told us about Mustang’s initial 2016 bulk sampling and exploration activities. The company hopes to become an important supplier of commercial and gem-quality ruby.

Marcello Ribeiro of Belmont Group updated us on developments at the company’s Belmont and Canaan emerald mines at Itabira, Brazil. He emphasized the importance of sound mine planning through fieldwork and trace-element analysis of potential emerald host rocks.

David Bindra of B&B Fine Gems confirmed the importance of the secondary market for exceptional gems, which are in very high demand. He noted less consumption of commercial to mid-grade material.

A partnership between Morocco’s Geostone Group and U.S. gem carver Glenn Lehrer illustrates another interesting development. Production from Geostone’s Moroccan amethyst mine is cut to Lehrer’s high standards in an Indian factory, featuring a branded designer cut with high weight retention. The resulting faceted stones—and finished amethyst jewelry—are sold directly to consumers through television merchandising. The approach helps build a niche for Moroccan amethyst and brings the benefits of scale to designer cutting, which is usually associated with unique pieces.

Eternity Emerald’s Arthur Groom shared his rough emerald buying expertise with us, especially his years of experience negotiating with miners in Afghanistan’s Panjshir Valley. He noted that the quality of Afghan emerald is not realized in the West because large, fine crystals are often damaged by improper blasting and extraction techniques.

Potentate Mining’s Warren Boyd showed us sapphire production from Montana’s Rock Creek alluvial deposits, including a remarkable 12.61 ct blue sapphire cut from a 6.37 g rough crystal. Although most of the production has greenish or brownish pastel colors, it reacts well to heat treatment. Boyd told us bright natural colors are in high demand. He showed several suites of fancy sapphires cut by his client, Americut. Montana’s alluvial sapphire deposits will be the subject of an upcoming G&G field report.

The trend toward ethical, sustainable business practices and transparent supply chains is exemplified by Sheahan Stephen of Sheahan Stephen Sapphires, Inc. His company documents and guarantees the integrity of the gems it sells from the mine, through treatment and cutting and directly to the customer.

Nigeria is an under-documented source of fine rubellite and indicolite tourmaline and predominantly blue basalt-hosted sapphire. For this reason, we especially welcomed talking to Zoe Michelou, who represented a Nigerian mining company. She updated us on production of these gemstones from that country’s Oyo, Kwara, and Taraba states.

Gem paintings, which GIA has documented in Vietnam and Mogok, made their first appearance at Tucson. Wanlaya Suwannapirom’s Than Thong Arts booth featured an array of art-inspired handmade portraits and miniatures. The technique converts otherwise unusable natural gem fragments into valuable art objects and wearable art such as pendants and pins.

Gem artist Alexander Kreis showed us a spectacular 27.20 ct freeform tanzanite complemented by a custom ring mount made by his mother Sonja, a master goldsmith. They related the importance of the story behind a jewelry piece for their clients—how details of the stone’s cut and the ring’s design represent the toil and effort of the Tanzanian miners and imbue the piece with added significance.

Fran Mastoloni provided a cultured pearl market update, explaining how careful selection and matching of the different cultured pearl types into a range of varied necklaces help him cater to the market’s desire for distinctive “fashion-forward” yet flexible jewelry.

Dealer Bill Vance of Vance Gems exhibited rare gem-quality magnesio-axinites from just one location in Merelani, Tanzania. This material displayed remarkable fluorescence, and we hope to report further on its chemistry in the near future.

We were delighted to find a Southwest-inspired Starship Enterprise, handmade by David Freedland of David R. Freedland Jr. Designs in sterling silver. This quirky blend of science fiction and traditional inlay work is one of the show’s unexpected finds.

Finally, no survey of the Tucson shows would be complete without Paula Crevoshay’s one-of-a-kind designs. This year, she showcased a bracelet featuring five large freeform fire opals, a swallowtail butterfly pin with yellow and black diamonds, an elephant pin with mother-of-pearl tusks, and a stunning cuff bracelet featuring a spectacular boulder opal centerpiece. Source: GIA @topic:7


Title: Tucson 2018 Overview Abstract: Figure 1. Although traffic at the AGTA show was lighter than in some previous years, demand was brisk and most traders were satisfied with their 2018 business. Photo by Kevin Schumacher.

Every February the gem and mineral world descends on Tucson, transforming the downtown convention center and a great many of the city’s hotels into a fascinating collage of traders bearing goods from all over the planet (figures 1 and 2).

Figure 2. Customers in Tucson sought out unique goods, a trend that carried over from last year's shows. Photos by Kevin Schumacher.
Many of the exhibitors we spoke with described 2018 as the strongest year since 2008. Although traffic wasn’t especially heavy at the AGTA and GJX shows, most dealers there enjoyed brisk sales and healthy demand for high-quality goods. Some of the same trends from last year were evident. Customers still sought out one-of-a-kind pearls and colored gemstone pieces, and the secondary market in the U.S. for exceptional pieces remained highly significant. There was a continuing focus on untreated material and ethically sourced gemstones, a subject articulated for us by Jean Claude Michelou of the International Colored Gemstone Association and officials from the Responsible Jewellery Council. Market realities such as very strong price competition for newly mined gem rough were mentioned as a major challenge by many dealers and cutters.

In addition to strong demand for high-end gems, many dealers at AGTA and GJX reported a surge in more moderately priced goods. Meanwhile, dealers at other locations told us the commercial end of the market remained soft.

Pantone’s color of the year for 2018, a shade of purple called Ultra Violet, was well represented at the shows. A couple of dealers had exceptional examples of purple sillimanite. Many dealers posted strong sales of pastel-colored spinel—in pink and lavender hues—in suites and sets as customers found the scarcity and high prices of red spinel prohibitive. In a similar vein, Margit Thorndal of Madagascar Imports reported strong demand for purple-lavender spinel and purple sapphire from Madagascar, as well as teal hues of unheated Montana sapphire.

We noted that electric blues, teals, hot pinks, hot yellow greens, and pastel-colored gems were quite popular. Bill Larson of Pala International pointed to this trend and showed us a number of spectacular examples from his inventory. Fine blue zircon from Cambodia was prominent, as was attractive sphene from Zimbabwe and Madagascar.

Figure 3. Dave Bindra of B&B Gems showed us a selection of standout gems from the secondary market, including this 61.92 ct Imperial topaz. Photo by Kevin Schumacher.
Dave Bindra of B&B Fine Gems said his company was very active in scouring the secondary markets for old jewelry items and gemstones that have been out of circulation for decades. This year’s standouts were two incredible red beryls from Utah (a 3 ct emerald cut and a 4 ct round brilliant), a 61.92 ct Imperial topaz (figure 3), and a fine selection of Kashmir sapphires, which were very sought after this year. Fran Mastoloni of Mastoloni Pearls updated us on current trends in the cultured pearl market and showed examples of unique pieces.

Dealers specializing in domestic gems reported strong demand. John Woodmark of Desert Sun Mining & Gems told us the market for Oregon sunstone was the strongest he had seen since the andesine controversy challenged suppliers of the natural Oregon gem a decade ago. As a result, the company has scaled up its mining activities and built new relationships with gem cutters to improve supply to its clients.

As always, the Tucson shows were a rich source for the latest on global colored stone supply. Conversations with Luis Gabriel Angarita and Edwin Molina revealed insights on the mining and branding of Colombian emerald. Marcelo Ribeiro shared details on mining and cutting at the Belmont emerald mine in Brazil. Alexey Burlakov offered his perspective on Russian demantoid production, while Stephan Reif did the same for demantoid from the Green Dragon mine in Namibia. Miriam Kamau shared information on her Kenyan tsavorite mining operation and offered her own inspirational success story. From Jürgen Schütz of Emil Weis Opals we learned about the cutting of opal, both play-of-color and nonphenomenal, from sources around the world. Alexander Arnoldi explained Arnoldi International’s strategy in sourcing and cutting high-quality aquamarine and tourmaline. We also saw examples of gem production from unexpected sources: Indonesian opal and turquoise from the state of Arkansas.

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Tucson is also a destination for many leading gem artists and jewelry designers. Award-winning carver Michael Dyber explained the inspiration behind some fantastic one-of-a-kind pieces bearing his signature optical disks. At the intersection of science and art, Rex Guo discussed his approach to recutting gems to optimize light performance and beauty. And designers Paula Crevoshay and Erica Courtney showed us striking and innovative new pieces with unexpected and fascinating gem combinations. Source: GIA @topic:10


Title: Zoning In on Liddicoatite Exhibit Abstract: Figure 1. At the 64th annual Tucson Gem and Mineral Show, the GIA Museum hosted Zoning In on Liddicoatite in honor of Richard T. Liddicoat’s 100th birthday. Photo by McKenzie Santimer.
The calcium-rich lithium tourmaline liddicoatite was first recognized as a new mineral species in 1977. It was named by research staff at the Smithsonian Institution after GIA’s then-president, Richard T. Liddicoat (1918–2002). In honor of Mr. Liddicoat’s centennial birthday, the GIA Museum hosted an exhibit titled Zoning In on Liddicoatite at the Tucson Gem and Mineral Show, February 8–11. With highlights from Mr. Liddicoat’s career alongside crystals and polished crystal slices showing spectacular color zonation (figure 1), the exhibit was a fitting tribute to GIA’s own “Father of Modern Gemology.” Source: GIA @topic:1


Title: Cabochons Fashioned from the Shell of Crassostrea Virginica Abstract: Figure 1. The ten cabochon-cut gems examined are shown alongside the valves of C. virginica (Eastern or American oyster). The interior and exterior valves shown belong to one oyster. Photo by Diego Sanchez; samples courtesy of Anne Dale.

Crassostrea virginica, the so-called Eastern or American oyster, is a commercial seafood widely distributed along the east coast of the United States to the Gulf of Mexico (“Indian River Lagoon Species Inventory,” Smithsonian Marine Station at Fort Pierce, 2008, https://www.sms.si.edu/irlspec/Crassostrea_virginica.htm). Connecticut, Virginia, and Mississippi have all designated the Eastern oyster as their official state shell, and cabochons cut from this bivalve are the official state gemstone of Louisiana (http://legis.la.gov/Legis/Law.aspx?d=103557). These specimens are marketed under the trade name LaPearlite.

Figure 2. Left: A 3.09 ct cabochon showed various surface structures consisting of a non-directional patchwork of cells near the center to a broad mottled appearance in the outer area, together with natural brownish layers of shell formation. Right: Higher magnification of another cabochon’s surface revealed a distinct patchwork structure. Both samples displayed a whitish sheen on the surface when illuminated with a fiber-optic light. Photomicrographs by Artitaya Homkrajae; fields of view 11.90 mm (left) and 5.24 mm (right).
The Carlsbad laboratory received ten LaPearlite cabochons together with a shell for examination (figure 1). The cabochons exhibited low domes and flat bases and ranged from 1.65 to 6.12 ct. They measured from 6.85 × 6.60 × 3.80 mm to 14.40 × 10.30 × 5.30 mm and possessed non-nacreous surfaces, with the majority displaying a natural brownish yellow banded structure typical of shell formation. Microscopic examination revealed that the main white surface and subsurface structure varied from a patchwork of nondirectional cells or segments to a broad mottled appearance within individual specimens, as well as from specimen to specimen. These structures exhibited a reflective whitish sheen when illuminated by a fiber-optic light or other bright oblique lighting, creating a shimmery phenomenon (figure 2). A similar patchwork pattern has been noted on scallop pearls and shells of the Pectinidae family (K. Scarratt and H.A. Hänni, “Pearl from the lion’s paw scallop,” Journal of Gemmology, Vol. 29, No. 4, 2004, pp. 193–203). Under long-wave UV radiation (365 nm), the white portions of all the cabochons and the shell were inert, while the yellow portions showed a weak to moderate yellow fluorescence, and the shell’s dark purple adductor muscle scar exhibited a weak red fluorescence.

Figure 3. Raman spectra collected using 514 nm laser excitation on the white and purple areas of the interior of the C. virginica valve. The white area shows calcite peaks at 280, 712, 1085, and 1437 cm–1, and the purple area shows aragonite peaks at 703 and 1085 cm–1, along with several broad pigment-related bands.

Figure 4. A PL spectrum collected using 514 nm laser excitation on a purple area on the interior of a C. virginica valve displays clear triple bands at approximately 620, 650, and 680 nm related to the porphyrin pigment.
Raman spectroscopic analysis with a 514 nm argon-ion laser subsequently verified that the white and yellow portions of the cabochons and shell were calcite with peaks at 280, 712, 1085, and 1437 cm–1. No peaks indicating the possible presence of pigments were detected in the yellow areas. Moreover, Raman spectra collected on the shell’s dark purple adductor muscle scar produced aragonite peaks at 703 and 1085 cm–1 along with several relatively weak broad pigment-related bands (figure 3). PL spectra collected with 514 nm laser excitation on the same areas showed clear triple bands at approximately 620, 650, and 680 nm (figure 4). The PL spectra and fluorescence reaction indicate the purple color is associated with the pigment porphyrin (Y. Iwahashi and S. Akamatsu, “Porphyrin pigment in black-lip pearls and its application to pearl identification,” Fisheries Science, Vol. 60, No. 1, 1994, pp. 69–71; L.H. Arma et al., “Red fluorescence lamellas in calcite prismatic layer of Pinctada vulgaris shell (Mollus, bivalvia),” Optical Materials Express, Vol. 4, No. 9, 2014, pp. 1813–1823). None of the studied cabochons showed purple areas to examine for comparison. Interestingly, the Raman spectra obtained from the white and purple areas of the same mollusk that were previously referenced in the literature (K. Scarratt et al., “A note on a pearl attached to the interior of Crassostrea virginica (Gmelin, 1791) (an edible oyster, common names, American or Eastern oyster),” Vol. 30, No. 1/2, 2006, pp. 43–50) differed slightly from the findings in Journal of Gemmology this work. The samples in this submission were also analyzed by energy-dispersive X-ray fluorescence (EDXRF) chemical analysis and showed low levels of manganese (Mn), confirming their saltwater environment.
As with all shell mollusks, C. virginica is capable of producing pearls. However, the cabochons in this study provided useful gemological and spectroscopic information for future reference that can no doubt assist with identifying the composition of pearls produced by the mollusk (C.P. Idyll, “The pearls of Margarita,” Americas, Vol. 19, No. 8, 1967, pp. 8–14). Although the samples could be mistaken for agate at first glance, owing to their distinctive banding, it would soon be apparent that they were pieces of fashioned shell. The samples demonstrate how creative work can turn nature’s beauty into an attractive gemological material. Source: GIA @topic:5


Title: The Granada Gallery Abstract: Figure 1. Paraíba-type tourmalines from Mozambique. Left to right: a 29.34 ct oval, a 3.01 ct pear set in a rose gold ring, a 51.62 ct oval, and a 65.17 ct trillion cut. They were displayed with a 224.6 g gold nugget from Victoria, Australia. Photo by Robert Weldon/GIA, courtesy of the Granada Gallery.

Housed in a 1908 vintage Arts and Crafts building on Granada Avenue in Tucson, the Granada Gallery is replete with what its owners call “items of geologic relevance,” or rare mineral and fossil specimens. These are carefully lit and displayed to accentuate their beauty and often combined with faceted and carved gem materials, one-of-a-kind objets d’art, and finished jewelry. For the visitor, this earth-to-jewel experience accentuates the jewelry industry’s rich history.
“We want to further an exchange of ideas between artists, scientists, curators, and collectors,” explained Rüdiger Pohl, who owns and curates the traveling gallery along with Alison Magovern. The gallery’s Tucson space has been open during the gem and mineral shows since 2013.

Figure 2. Pezzottaite is carved into a coiled dragon by Patrick Dreher. The pezzottaite crystal measures 9.6 × 4.7 × 2.1 cm, while the carved pezzottaite is 201.03 ct. Photo by Robert Weldon/GIA, courtesy of the Granada Gallery.

Figure 3. Left: Jochen Leën’s aquamarine and gold bracelet is displayed with a 6.1 × 9.1 × 8.5 cm (369.2 g) aquamarine crystal from Pakistan. Right: This 3436 g aquamarine from the Pohl collection measures 5.0 × 9.4 × 7.5 cm, and is also from Pakistan. Aside from its quartz overgrowth, the crystal exhibits phantom growth features and iridescence. Photos by Robert Weldon/GIA, courtesy of the Granada Gallery.
The Granada Gallery collaborates with global artists and collectors, “sparked by happy coincidences, shared visions, and the passion for creating something unique,” the owners said. This year’s exhibit included a collection of Paraíba-type tourmalines from Mozambique (figure 1) and a stunning dragon—carved from the rare mineral pezzottaite, found in a single deposit in Madagascar—by Patrick Dreher (figure 2). Pakistani aquamarine was on display in rough and mounted forms (figure 3). And a year-long collaboration with the Kreis family of Idar-Oberstein, Germany, resulted in their “Chanting of the Stars” piece (figure 4).

Figure 4. “Chanting of the Stars” was created by the Kreis family of Idar-Oberstein. The “chanting” refers to the sound of a comet entering the earth’s atmosphere. The rutilated quartz comet’s impact with earth is denoted by the smoky quartz carving. Photo by Robert Weldon/GIA, courtesy of the Granada Gallery. Source: GIA @topic:9


Title: Ponderosa Sunstone Update Abstract: Two Oregon sunstones weighing 7.07 and 2.48 ct. The stone on the right, faceted by Larry Woods, has a very rare deep red color. Photo by Robert Weldon/GIA, courtesy of John Woodmark, Desert Sun Mining.

John Woodmark, president of Desert Sun Mining and Gems (Depoe Bay, Oregon), updated us on the Ponderosa mine, which he calls the most productive source of Oregon sunstone (see above). Demand has increased annually over their 17 years of production, he said. With the larger excavator and high-capacity screen they brought on in 2015, they now mine about 4,300 kg (4.8 tons) of sunstone rough per year, up from about 2,000 kg (2.2 tons) in 2014. About 3% of this material is facet grade. Ponderosa now produces 4,000 to 5,000 cubic yards of concentrate in seven days—more than enough to process in one season (which only lasts five or six months due to snow at the high elevation). Desert Sun was once limited to mining at about 50 feet deep, but the excavator has allowed them to go a few hundred feet deep into the source. Woodmark said the sunstones at that depth are larger and less fractured, and there are some excellent red stones of good size.
Woodmark said demand is especially strong from American and European customers age 45 and under because they want natural, untreated gemstones such as sunstone, opal, and jade. They also love Oregon sunstone’s schiller effect, a sparkle caused by reflective copper platelets that makes the stone “different from what their friends have.” Desert Sun will be using social media this year for the first time to reach customers looking for unique gemstones.
Jewelers are excited about Oregon sunstone because of the potential high markup, according to Woodmark. He noted that sunstone isn’t competing with diamond, ruby, sapphire, and emerald, for which a jeweler might see a 10% or 15% profit margin. Oregon sunstone can yield a triple or quadruple markup, yet it is still relatively affordable: Woodmark said the yellow sunstones sell for about $30 per carat while the reds can go for $300 to $4,000 per carat. Sunstone’s affordability, profit margin, and appeal to young consumers make it attractive to jewelers.

	John Woodmark updates us on the Ponderosa mine and the sunstone market.

Woodmark said the jewelry industry’s demand for calibrated sunstones continues to grow, and Desert Sun now receives significant orders from large companies. A typical order might be a thousand 5 mm rounds of orange sunstone. Every color sells well, he told us, but it is difficult to get a specific band of color in natural, untreated gemstones, so they are trying to grade more consistently. Desert Sun has seven colors, each graded with and without schiller, so overall there are 14. He tries to educate jewelers, manufacturers, and designers on the fact that color in natural stones is more variable—and that many have unique color—to encourage them to use more than one color in their pieces.
Woodmark sees a bright future for Oregon sunstone as more consumers become aware of it. He acknowledged that there will come a time when he and Bruce Moore, Desert Sun’s executive vice president, will have to step away from the deposit. “We’re barely scratching the surface of what people could do with this mine,” he said. Desert Sun only exhibits at the AGTA show in Tucson, but Woodmark said if someone were to take over the mine, they could do 10 shows a year across the United States. At that point, he said, sunstone would “take off.”

	Sonja Kreis describes an Oregon sunstone and gold nugget piece by Kreis Jewellery. Source: GIA @topic:1


Title: Emerald in Rock Crystal Quartz Abstract: A prismatic emerald crystal within a rock crystal quartz. Photomicrograph by Nattida Ng-Pooresatien; field of view 12.5 mm.

Rock crystal is a transparent and colorless macrocrystalline variety of quartz (SiO2) that often has cavities containing liquid and gas two-phase inclusions. Many different minerals also form as inclusions within rock crystal quartz. Typical varieties of included quartz for gem use are rutilated quartz, tourmalinated quartz, and strawberry quartz. Specimens may also contain several other types of mineral inclusions.
Recently, the author examined a 10.95 ct rock crystal quartz cabochon that contained elongate rod-shaped green crystals (see above). The green crystals showed hexagonal cross-section and were identified by Raman spectroscopy as beryl. Ultraviolet/visible/near-infrared (UV-Vis-NIR) spectroscopy showed a chromium (Cr) spectrum, which confirmed that the green crystals were emerald. This amazing inclusion has been previously reported in a rock crystal quartz specimen (Fall 2008 Lab Notes, p. 258), but this is the first time the author has examined a gem-quality rock crystal quartz cabochon with a perfectly hexagonal emerald crystal inclusion. Source: GIA @topic:3


Title: Dravite from Mozambique with an Abundance of Pyrite Inclusions Abstract: Figure 1. Six yellow to brownish yellow faceted dravite tourmalines (0.47–2.8 ct) from Mozambique, many of which contained distinct metallic inclusions of pyrite. Photo by Weizhi Huang.

In the summer of 2017, author JP encountered a parcel of transparent yellow to brownish yellow tourmalines at the gemstone market in Chanthaburi, Thailand. The six faceted tourmalines shown in figure 1 revealed properties consistent with tourmaline. LA-ICP-MS analysis was performed to determine their major chemical components, which were: 11.56–12.31% MgO, 9.98–10.34% B2O3, 2.62–2.82% Na2O, 0.68–1.06% CaO, 0.17–0.45% TiO2, and 0.11–0.25% FeO (total iron). Minor amounts of Li, K, V, Cr, Mn, Zn, Ga, and Sr were also detected, indicating dravite tourmaline.

Figure 2. The dravites contained distinctive inclusions of pyrite, which were confirmed by Raman spectrometry. Photomicrograph by Weizhi Huang; field of view 0.8 mm.
These dravites were noteworthy for their numerous euhedral pyrite crystal inclusions (figure 2), confirmed by Raman. This was previously reported without Raman analysis (see Spring 2007 GNI, pp. 73–75). This is the first time the authors have seen so many intact pyrite crystals in yellow to brownish yellow gem-quality dravite from Mozambique. Source: GIA @topic:2


Title: Dive Into Summer: Mozambique Ruby, Madagascar Sapphire, and Black Nephrite from China, Plus an Opal Inclusions Chart Abstract: With 2019 already past the halfway mark, we are very pleased to present our Summer edition. Inside you’ll find new insights into a variety of gem materials.
The issue leads with a review of the past decade of ruby from Mozambique. Since 2009, Mozambique has become the world’s leading supplier of ruby, transforming the market in the process. GIA has been visiting these deposits since the initial discoveries, and now Wim Vertriest and Sudarat Saeseaw from the Bangkok laboratory add a new chapter to this story with an overview of production and distribution, as well as a comprehensive gemological characterization and a discussion of the most common treatment processes applied to material from this important locality.

“Since 2009, Mozambique has become the world’s leading supplier of ruby, transforming the market in the process.”

Next, Billie Hughes from Lotus Gemology and Rosey Perkins with Fura Gems present the results of low-temperature heat treatment experiments on sapphire from Madagascar. Increasing numbers of these stones are being heated to relatively low temperatures (below 1350°C) to lighten their color. The authors show the changes in these goods, providing a means of separating unheated and heated Madagascar sapphire.
Moving from Africa to Asia, the issue continues with a study of black nephrite from a deposit in southern China. Qian Zhong, a PhD student of mineralogy at Tongji University in Shanghai, leads a team of professors from that university in characterizing 12 nephrite samples from the Guangxi region.
In the fourth article, Jean-Pierre Gauthier from the Gemological Research Center of Nantes and his coauthors characterize “flame structure” in 37 pearls from bivalves of the Tridacnidae family. Careful observation revealed evidence of rotation during growth, a feature also seen in numerous pearls from Pinctada margaritifera.
The next article, also on pearls, presents an unusual identification challenge that confronted researchers at the Max Planck Institute for Chemistry, Johannes Gutenberg University, and GIA’s New York and Bangkok laboratories. Two pearls were examined by the team of authors, who were unable to positively identify their origin (natural or cultured), their growth environment (freshwater versus saltwater), or the mollusk that produced the pearls.
In our last article, Nathan Renfro and coauthors present an opal inclusions chart, the fifth in their series on micro-features in gemstones. Laminated versions of all of these large, colorful wall charts are also available at store.gia.edu.
Highlights from the Lab Notes column include a rough diamond with a coating of fake green “radiation stains,” a study on the separation of kornerupine and prismatine, and the first report of a color-change spessartine garnet examined by GIA. Gem News International features brief but thorough studies on the gemological characteristics of jadeite from the Polar Urals of Russia, more than 800 natural freshwater pearls from the Mississippi River system, and rubies from the Rock Creek deposit in Montana. As always, Micro-World reveals a fascinating gallery of inclusion scenes, while the Diamonds from the Deep section (now a year old) outlines the basic geological and practical features of kimberlites, the earth’s diamond delivery system.
We hope you enjoy the Summer 2019 edition of Gems & Gemology! Source: GIA @topic:1


Title: Citrine from Zambia Abstract: Figure 1. These citrines (3.38–43.86 ct) showing the range of color from the new Zambian deposit are reportedly untreated. Photo by Robert Weldon.

                      In September 2011, GIA was informed by gem and mineral dealer Dudley Blauwet about a new find of citrine, which was represented to him as natural-color material from the Kitwe area of Zambia. He obtained ~1 kg of the rough at the 2011 Tucson gem shows from a regular supplier of African rough. Faceting of 208.5 grams of rough yielded 29 stones totaling 268.08 carats. Four of the stones were concave cut, and the largest one weighed 48.69 ct.

	Figure 2. Hazy clouds and bands are common features in the Zambian citrine. Photomicrograph by D. Beaton; image width 2.7 mm.
Mr. Blauwet loaned seven of the cut citrines to GIA for examination, ranging from 3.38 to 43.86 ct (figure 1). Concave facets on the three largest pieces accentuated their brilliance. The color of the citrine ranged from pale slightly brownish yellow to brownish orangy yellow, and the seven stones showed the following gemological properties: RI— no = 1.542, ne = 1.552; birefringence—0.010; hydrostatic SG—2.65–2.66; UV fluorescence—inert to both long- and short-wave UV radiation, except for one pale yellow sample that fluoresced very weak white to long-wave UV; and no features seen with the desk-model spectroscope. Microscopic examination revealed straight and angular color zones, as well as a general haziness and bands of hazy particles (figure 2), which proved natural origin and were similar to those described in citrine from Sri Lanka (E. J. Gübelin and J. I. Koivula, Photoatlas of Inclusions in Gemstones, Vol. 2, Opinio Publishers, Basel, Switzerland, 2005, p. 573). The 3.38 ct stone also contained a plane of parallel tubules and two-phase inclusions (figure 3). Viewed with cross-polarized light, minor areas of Brazil-law twinning were seen in only the two smallest samples.

	Figure 3. The 3.38 ct triangular modified brilliant in figure 7 contains a plane of elongated
	tubules and two-phase inclusions. Photomicrograph by D. Beaton; image width 1.5 mm.
FTIR spectroscopy revealed the absence of a 3595 cm–1 band. This feature is sometimes used as confirmation of natural quartz, especially amethyst, when it is well resolved and there are no diagnostic natural inclusions (S. Karampelas et al., “Infrared spectroscopy of natural vs. synthetic amethyst: An update,” Fall 2011 G&G, pp. 196–201). In citrine this feature is often absent, so proper identification must rely on inclusion observation, or the analysis of trace elements (C. M. Breeding, “Using LA-ICP-MS analysis for the separation of natural and synthetic amethyst and citrine,” www.gia.edu/gia-news-research-nr73109a).

Natural-color citrine is less common than other quartz varieties such as amethyst and smoky quartz. Assuming that the coloration of this citrine is natural—as represented by the supplier—this large, clean material makes a nice addition to the gem market. Source: GIA @topic:1


Title: The Anahí Ametrine Mine, Bolivia Abstract: The Anahí mine, Bolivia, has produced large amounts of amethyst, citrine, and amethyst-citrine for the gem market. Field and experimental investigations conclusively show that the amethyst-citrine color combination in quartz crystals from Anahí is natural and does not result from laboratory treatment. The unusual color patterns probably result from the uncommon geologic conditions under which these quartz crystals formed, although the crystal chemical properties controlling the sector color zoning still elude explanation. From 1989 to the present, more than 100 tons of ametrine crystals, yielding 40-80 kg of cutting rough per ton, have been produced. Source: GIA @topic:2


Title: Emeralds: Colombia’s Buried Treasure Abstract: A miner holds an emerald in the mine office in the village of Coscuez, Colombia. Photo by Eric Welch/GIA

No one can be more familiar with or cherish the magnificent emerald more than the miner himself. At the end of a long day of labor, the miner illuminates and holds firmly the prize of the day.

Miners in Colombia have unearthed the world’s most sought after and valuable of the green gemstones. The characteristic rich greens unique to Colombian emerald are historically appreciated more than any other locality on Earth.

To chart a “treasure map” of Colombia’s finest gemstones, start in the capital of Bogota. From there, draw a line due north for approximately 200 km (124 miles), into the Cordillera mountains of the Andes. Then, strike an arc 90° due east.

Buried within this quadrant, you will find some of the finest emeralds in the world, as verdant as the rainforest, mountains and valleys where they have been buried for millennia − and sought after for centuries. The renowned colored gemstone localities of Muzo, Coscuez and La Pita lie to the north, and Chivor to the east.

Lake Guatavita, 120 km (75 miles) west of Chivor, is steeped in legend and lore, garnished with flecks of truth. The raft of El Dorado (The Golden Man) from the Muisca period depicts a ceremony on the sacred lake. It is said that the legendary El Dorado would be covered in gold dust daily and bathed in the waters of Lake Guatavita.

Spanish and English Conquistadors in the 16th and 17th centuries avidly sought the ceremonial gold dust and precious jewels thrown into the lake.

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The pre-Columbian emerald and gold jewelry seen in the gallery above could very well be examples of the types of emerald jewelry used in these rituals and spurred European Conquistadors in their search for the gold and jewels of El Dorado.

La Pita, another well-known emerald mining locality, is home to Itoco, a mythical mountain peak named for the son of queen Fura and her husband Tena. Legend says that tears shed in the tragic love story of Fura and Tena turned into beautiful green stones that lay buried underground.

Emeralds are not the only treasure buried in the verdant land of Colombia. Rubies, sapphires and diamonds are also found there, though more rarely. Feast your eyes on the rainbow of colors of gemstone treasures from deep within the land of Colombia—red rubies, blue sapphires and yellow diamond. Source: GIA @topic:1


Title: Unusual Faceted Gemstones Abstract: Figure 1. A pink 173.22 ct fluorite, measuring 35 × 33 mm, from Uri, Switzerland. This stone is representative of minerals discovered by strahlers, mineral hunters from the Swiss Alps. Photo by Kevin Schumacher, courtesy of Gravier & Gemmes.

Denis Gravier of Gravier & Gemmes (Poncin, France) exclusively sells rare and unusual faceted stones, such as the pink fluorite from Switzerland shown in figure 1. During the GJX show, he shared insights about the market for such gems.
Gravier developed a passion for colored stones and minerals while growing up in the French countryside. He studied mineralogy, crystallography, and petrology before traveling to the Republic of the Congo, Pakistan, Mexico, the former Yugoslavia, and Morocco a few decades ago to collect mineral specimens. He also learned gemstone cutting techniques. With the knowledge and experience he gained, he decided to open a company specializing in faceted stones of unusual varieties. Some of these gems, he explained, are rarely if ever used in jewelry. The challenge is finding them, but after decades of traveling and visiting the mines, he knows many people in the trade. Now the stones come to him during major shows, so it is no longer necessary to go to the sources. He still travels occasionally to Sri Lanka and Madagascar, where he buys rough that he will have cut in France or overseas. Gravier says Tucson “is a great show…you can almost see all that is available in the world at that time during the show.” In Tucson he meets with clients from the U.S., Japan and other parts of Asia, and European countries.
In terms of novelty and rarity, Madagascar offers the largest variety and supply. New gemstones are always emerging, Gravier explained. Among his stones from Madagascar were the dumortierite and green sphene in figure 2.

Figure 2. Unusual stones from Madagascar. Left: A 0.51 ct dumortierite (5.4 × 4.5 mm). This mineral, commonly known as an inclusion, is now available in very limited quantities as a gem. Right: A 19.65 ct round-cut green sphene. Photos by Kevin Schumacher, courtesy of Gravier & Gemmes.

Figure 3. A 1.21 ct intense yellow legrandite, a rare zinc arsenate mineral from Mexico. Since the last discovery of this mineral in the 1970s, it has appeared on the market only sporadically. Photo by Kevin Schumacher, courtesy of Gravier & Gemmes.
He also described the market for unusual faceted gems. Collectors, not the jewelry industry, are the clientele for rare stones in France and around Europe, which is dominated by the “Big Three” and diamond. Faceted legrandite (figure 3), grandidierite, and dumortierite, for example, are generally not used in jewelry pieces. On the other hand, in Asia, especially Japan, people are attracted by rarity and there is a demand for “exotic” quality material, even in small sizes, for use in jewelry. Gravier feels that more people there have a general knowledge of and interest in gemology and colored stones. The Chinese market is becoming increasingly important for his business. One benefit of the rare stone market is that treatments are not common among these gems, making it a good source for people seeking untreated material.
Even though there is growing competition, with goods at all price points available on the Internet and aggressive marketing through the web and social media activity, Gravier chooses not to sell on the Internet. He invests in improving the quality and variety of his stock, relying on his long-term relationships with clients and suppliers.
Gravier sees a rising interest in rare stones. He believes he is helping to create more appreciation for a wide range of colored stone varieties. He hunts for rare treasures and, as an ambassador for unusual stones, gives them a chance for public exposure and recognition.

	Unusual Faceted Gemstones Source: GIA @topic:1


Title: “Paraíba”-Type Copper-Bearing Tourmaline from Brazil, Nigeria, and Mozambique: Chemical Fingerprinting By LA-ICP-MS Abstract: Gem-quality bright blue to green “Paraíba”-type Cu-bearing tourmaline is now known from deposits in Africa (Nigeria and Mozambique), in addition to three commercial localities in Brazil (in Paraíba and Rio Grande do Norte States). Stones from these new localities have been mixed into parcels from the original Brazilian Paraíba occurrence. The Nigerian and Mozambique tourmalines that show saturated blue-to-green colors cannot be distinguished from the Brazilian material by standard gemological testing or on the basis of semi-quantitative chemical data (obtained by EDXRF analysis). However, quantitative chemical data obtained by LA-ICP-MS show that tourmalines from the three countries can be differentiated by plotting (Ga+Pb) versus (Cu+Mn), (Cu+Mn) versus the Pb/Be ratio, and Mg-Zn-Pb. In general, the Nigerian tourmalines contained greater amounts of Ga, Ge, and Pb, whereas the Brazilian stones had more Mg, Zn, and Sb. The new Cu-bearing tourmalines from Mozambique showed enriched contents of Be, Sc, Ga, Pb, and Bi, but lacked Mg. Source: GIA @topic:12


Title: Fine Corundum, Paraíba Tourmaline, and Alexandrite – Tucson 2014 Abstract: Figure 1. This remarkable 112.82 ct Sri Lankan alexandrite, seen under incandescent (left) and fluorescent lighting (right), is unusually large. Photos by Robert Weldon; courtesy of B&B Fine Gems.

              At the AGTA show, Dave Bindra (B&B Fine Gems, Los Angeles) showed us an exceptionally large fashioned alexandrite reportedly from Sri Lanka (figure 1). According to Bindra, it is very difficult to find fine specimens over 5 ct, although Sri Lanka and Madagascar are known to produce sizeable alexandrite crystals. At over 100 ct, this is certainly one of the largest our team has seen. Bindra speculates that the original crystal may have been over 300 ct.

	Figure 2. This heated 33.16 ct emerald-cut royal blue sapphire is from Sri Lanka. Photo by Robert Weldon; courtesy of B&B Fine Gems.
Also on display was a royal blue emerald-cut Sri Lanka sapphire weighing over 33 ct (figure 2). Bindra noted that supply of fine sapphire, while scarce, is currently stronger than fine ruby. Compared with rubies of equivalent price, fine sapphires offer more size and quality; as a result, prices have risen dramatically over the last two years. This is a function of constricted supply and increasing demand as the Chinese market opens up to premium goods. Only three to five years ago, the strongest demand from Chinese buyers was for mid-range to commercial material. The Chinese are currently consuming the finer items once sought only in Western Europe, the United States, and Japan. As a result, U.S. dealers and consumers have to contend with competition in this market. As Bindra pointed out, this creates “a very interesting dynamic.”

	Figure 3. Fine rubies were scarce and expensive at the 2014 Tucson gem show. According to the dealer, this 9.10 ct Mozambique ruby had only undergone low-temperature heating. Photo by Robert Weldon; courtesy of B&B Fine Gems.
Also at the B&B booth was a superb 9 ct Mozambique ruby (figure 3), one of the finest rubies Bindra has seen from this source. He explained that Mozambique’s rubies are so popular because they come in large, strongly colored crystals; once cut, they produce clean, attractive gemstones. They are very marketable because consumers readily appreciate their beauty. Bindra told us that Mozambique ruby crystals can be a little flat, which constrains the depth of fashioned stones. It is difficult to find a piece of rough above 4–5 ct with fine color suitable for cutting a clean gemstone; this makes the 9 ct ruby exceptional. A gem of this quality might sell for US$50,000 per carat or more.

By comparison, Burmese rubies are increasingly difficult for domestic dealers to obtain due to the U.S. embargo against Myanmar. Trade is limited to gems that predate the ban and were already in circulation in the United States.

	Figure 4. Dave Bindra shows off a superb 14.59 ct oval faceted Brazilian Paraíba tourmaline. Gems of this quality above 1 ct are extremely rare, making this gem exceptional. Photos by Eric Welch (left) and Robert Weldon (right); courtesy of B&B Fine Gems.
Finally, Bindra showed us what he described as the star of his show: a 14.59 ct Brazilian Paraíba tourmaline, reportedly unheated (figure 4). He was fortunate enough to acquire this stone out of a collection. The previous owner had purchased it years ago when the material first came out, making this another example of recirculation rather than current production. Bindra confirmed the importance of the secondary gem market, which has become critical to dealers because there is so little material coming from deposits. With so much competition at the source—especially when a deposit, such as Paraíba, is reportedly depleted—dealers have no choice but to look in the secondary market. Source: GIA @topic:1


Title: Oregon Sunstone Update Abstract: Figure 1. Fashioned by lapidary Jean-Noel Soni, this 35.50 ct mixed-cut sunstone is reportedly from a mine on Eagle Butte, in Oregon’s remote Harney Basin. Photo by Robert Weldon/GIA; courtesy of Suncrystal Mining.

At the GJX Show, Nirinjan Khalsa (Suncrystal Mining, Lake and Harney Counties, Oregon) showed us a remarkable 35.50 ct rich orangy red Oregon sunstone fashioned into a modern mixed-cut cushion by lapidary Jean-Noel Soni (Top Notch Faceting). This stone (figure 1) resembled a fine ruby under the showcase lights and was one of the most exquisite examples we had seen.

At Khalsa’s request, we followed up with Soni after the show. He told us the original rough weighed 198.82 ct. As is typical with Oregon sunstone, the rough contained spots of strong red or green color in the cores of otherwise yellow or near-colorless crystals. This crystal had two color spots, so he divided it, and this gem was the first of two he intended to cut. Rather than using CAD software to design his gems’ faceting styles, Soni treats each rough as unique and individual, cutting to maximize color and luster. He explained that the pavilion had to be deep, due to sunstone’s relatively low RI (1.563–1.572). This produced a 63.00 ct preform, from which he faceted the 35.50 ct gem we saw. The asking price for this gem—reportedly from one of the mines on Little Eagle Butte (in Harney Basin, near Plush, Oregon)—was in the region of $60,000.

Also at the GJX show, Don Buford and Mark Shore (Dust Devil Mining, Plush, Oregon) gave an update on their operations. They said 2014 was a good year at Dust Devil. They uncovered a former dried creek bed where the basalt was extensively decomposed, which has allowed easier recovery of the sunstones. Buford hopes to have the mine’s optical sorter operational for the 2015 mining season.

	Dust Devil Mining - “My precious” sunstone

Dust Devil “executive ore relocator” Mark Shore talks about the mine’s current operations. He also proudly displays his new favorite sunstone: a 156 ct “watermelon” crystal he plans to have made into a unique carving.
Shore showed us an exceptional 156.00 ct “watermelon” sunstone from recent production (figure 2). The stone has a red center surrounded by a greenish “rind.” Shore has made arrangements to have it carved by Dalan Hargrave, winner of multiple AGTA Spectrum Awards.

Figure 2. This 156.00 ct rough sunstone belongs to the Dust Devil mine’s Mark Shore and will likely become a fine carving. Photo by Duncan Pay/GIA; courtesy of Mark Shore.
At the 22nd Street show, Terry Clarke, co-owner of the Dust Devil mine, explained a recent initiative to maintain the integrity of natural, untreated Oregon sunstone and promote it to retailers and consumers as a rare and desirable “all-American” gemstone. Called the Oregon Sunstone Miners Association (OSMA), the organization includes most of the miners with working claims or mines in Lake and Harney Counties (figure 3). OSMA also offers an associate membership for sellers of loose gems or jewelry. Anyone purchasing sunstone from an OSMA member can be assured they are getting the natural, untreated Oregon product. The intention is to expand the marketplace for this unique gem and maintain stability and consumer confidence in the event of an influx of treated material from another source. The association’s website is www.oregonsunstonema.com.

Figure 3. Dust Devil Mining’s Terry Clarke holds a flyer promoting the Oregon Sunstone Miners’ Association. Photo by Duncan Pay/GIA; courtesy of Dust Devil Mining.

	Dust Devil Mining

In this interview, Terry Clarke, co-owner and president of Dust Devil Mining, explains the recently established Oregon Sunstone Miners’ Association (OSMA).
At the AGTA show, John Woodmark (Desert Sun Mining & Gems, Depoe Bay, Oregon) provided an update of his operations at the Ponderosa mine and summarized the current market for his goods. He showed us a striking 2.77 ct “spinel red” gem from recent production (figure 4).

Figure 4. This 2.77 ct “spinel red” sunstone, measuring 10.5 × 8 mm, is from Oregon’s Ponderosa mine. Photo by Robert Weldon/GIA; courtesy of Desert Sun Mining & Gems.
According to Woodmark, 2014 saw heightened interest in Oregon sunstone. He received requests for rough from clients in Australia and for finished stones from Brazil and Europe (principally the UK and Germany). At this particular show, Woodmark said he had received many more inquiries from domestic jewelers for samples and information, all following customer requests due to growing public awareness of the gem. He cited a TV shopping channel’s recent promotion of production from the Sunstone Butte mine and the growing reach of his Internet business. For more information on the Sunstone Butte mine, see www.gia.edu/gia-news-research-butte-sunstone.

Woodmark observed that Internet merchandising, often by TV jewelry shopping channels, has been transformative for low-volume, one-of-a-kind products like Oregon sunstone. Web marketing frees traditional TV merchandisers from the production costs of on-air hosts and studios, and allows the cost-effective presentation of a spectrum of Oregon sunstone from “bargain parcels” to unique designer cuts costing several thousands of dollars per piece. According to Woodmark, one buyer for a major TV jewelry retailer at the Tucson shows said that Internet business was now 40% of the company’s total sales volume.

Woodmark estimated the total volume of fashioned Oregon sunstone on the market in 2014 was approximately 70,000 carats. By his calculations, that would be sufficient to supply one large U.S. retail jewelry chain with 10 carats per store per month over the course of a year. If demand picks up in 2015, that volume will not meet the industry’s needs. Woodmark reported that business was up 25% on the previous year’s show, which was up one-third on the year before.

In the 2014 mining season, Woodmark employed up to five pickers working the screens. He worked the mine for a total of 20 days and produced almost 2,000 kg of rough in all grades. Woodmark plans to work for 40 days in 2015 and expects to recover 4,000 to 5,000 kg of rough. To start the upcoming mining season, Woodmark will bring in heavier machinery and extend the pit back into the hillside. He will also bring in a bulldozer with a ripper to tear up the pit floor and start moving downward, too. Late 2014 saw recovery of larger rough, some pieces up to 70 grams (figure 5). In addition, the pit’s “red zone,” with a higher proportion of red-cored rough (up to 20%), remained productive. Woodmark expected the trend of bigger, better stones to continue as the miners work deeper into the deposit. This is similar to the situation at Sunstone Butte, he remarked.

Figure 5. The 2014 season saw some larger rough sunstone from Ponderosa mine in the 20–70 gram range. As operations go deeper, stone size seems to increase. Photo by Duncan Pay/GIA; courtesy of Desert Sun Mining & Gems.
Anticipating higher demand, he also planned to cut more frequently in 2015. Rather than cutting two to three times per year, he will cut 2,000 to 4,000 kg per month (new production plus stockpiled rough), depending on his needs. As 4,000 kg equates to approximately 2,000 carats of finished stones, Woodmark expected his production to significantly increase market availability of Oregon sunstone in 2015.

Like all the Oregon sunstone mines, Ponderosa produces a substantial quantity of yellow and near-colorless labradorite—material with little or no pink or red and no visible coppery reflections. One of the things Woodmark has learned at this show is the importance of cutting style and quality on a gem’s perceived value. He sold 2 kg of yellow rough to another vendor at the AGTA show—Ken Ivey (Ivey Gemstones, Prescott, Arizona)—and was astonished at the result.

Ivey’s use of concave cutting styles (figure 6) presented the feldspar’s bright yellow color far more effectively than conventional cuts. With conventional cutting, Woodmark struggled to get a few tens of dollars per carat for yellow goods. With only a modest investment in extra cutting costs for concave faceting—perhaps twice the expenditure—the same material can sell for up to five times as much. As the yellow rough sells for a couple hundred dollars per kilogram, this is a potentially significant value addition in the finished product.

Figure 6. The concave cutting style used on these Oregon feldspars accentuates their yellow color and raises the market value of the material. Photo by Duncan Pay/GIA; courtesy of Ivey Gemstones.
Another encouraging trend Woodmark sees is that designers and jewelers are mixing calibrated sunstones of different shapes and colors in the same jewelry piece. The casting is standardized, but because every combination is unique there is no longer the need to match them. Volume business with sunstone jewelry has always been hampered by the perception that every stone in a piece has to match and every piece must be uniform.

In Woodmark’s opinion, even home shopping channels like QVC are moving away from that concept, in essence marketing the uniqueness of the gem rather than a uniformity it can never provide. He cited a piece for which he supplied 3.0, 4.0, and 5.0 mm calibrated gems. One was a top-quality red sunstone, and the others were paler pink. In this way, the manufacturer does not have to match the stones and can use larger volumes. Source: GIA @topic:1


Title: A Sunstone Odyssey, Part 1: The Ponderosa Abstract: John Woodmark, CEO of the Ponderosa mine, is a man in his element. Photo by Robert Weldon.

THE MINE'S LOCATION

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	In this slideshow, you will explore the Ponderosa mine, learn about its gem recovery processes, and view the beautiful sunstones that originate in the rocks of southeastern Oregon.
With a sweep of his arm, John Woodmark invites us to take in the majestic vista below: “You can see the large meadow… it stretches for miles. That used to be an ancient lake…Native American people have been in here for 15,000 years, hunting around that lake.” He adds some more-recent history, telling us: “Into the 1900s, they were still camping in this area and using the dried-up lake bed as pasture for their horses.”

This connection to the native people extends to the present day. Woodmark partners with the local tribal outreach program to offer seasonal employment to Native American teens at the Ponderosa mine. This is something Woodmark is very proud of, and we’ll return to it a little later.

Right now, we’re standing on the steep slopes of Donnelly Butte, just above the Ponderosa mine’s pit. At our backs, magnificent stands of lofty ponderosa pines extend uphill. We are about a five-hour drive from Portland, Oregon, and the transition from that busy city to the silence and serenity of the Ponderosa is jarring.

Beneath us, entombed in an ancient lava flow, millions of carats of rough sunstone—Oregon’s state gemstone—await discovery. The Ponderosa mine is possibly the state’s most important source of the repeatable commercial sizes required by jewelry manufacturers.

	The red rocks of the Ponderosa mine’s pit complement the setting sun. Photo by Robert Weldon.
The beauty of the mine’s location isn’t lost on Woodmark: “It’s a pristine area, it’s beautiful…It’s wonderful just to come up here, let alone find a truly exotic gem like Oregon sunstone.” With this in mind, he strives to make his mining activities as low-impact as possible: “We’ve got over a million board feet of huge ponderosa, most of them in the 250 to 300 year old range, and we’re trying very hard not to disturb any of those trees and still get the same stones that we need to mine.”

Beyond the direct environmental impact, Woodmark and his crew also have to synchronize their mining to the regional climate. These are Oregon’s High Lava Plains, after all, and the winters can be brutal: “The mine is located at 5900 ft., so from October to June we’re covered with as much as ten feet of snow up here, so there’s absolutely no mining during those months.”

Despite these constraints, he knows the Ponderosa’s weathered reddish basalts are blessed with high concentrations of sunstone: “This mine is tremendously rich—the whole mine is 60 acres—and we get a kilo and a half of sunstone out of every cubic yard of dirt moved…so it’s arguably one of the richest gemstone mines in the world.”

Because of the richness of this deposit and the weathered nature of the basalt around the gems, they’re easier to recover than at some of Oregon’s other sunstone locations. Woodmark explains: “We do ten-day mining stints…sometimes four to five times throughout that four month period…It all depends on the demand for Oregon sunstones…the more demand, the more often we mine.”

	Introducing the Ponderosa

	John Woodmark, CEO of Desert Sun Mining & Gem, provides a brief history of the mine and its location, as well as explains how the Ponderosa’s location at 5,900 ft. affects the mining season.

BEAUTIFUL SUNSTONE
Woodmark is passionate about sunstone: “You never get tired of it…it isn’t like you’re mining amethyst, which is all purple. Ours is so many different colors, every stone is unique.” As he talks on, his enthusiasm and love of this unique gem is infectious: “You can get reds, with just a sprinkling of the copper platelets, which makes it look like you’re looking into a red sky with gold stars…It’s just gorgeous.”

	A rare 11.76-ct. bicolor sunstone gleams with an added bonus of glittering, reflective copper platelets. Photo by Robert Weldon.

	This group of red sunstones reflects recent production from the mine’s pit. Photo by Robert Weldon.
He draws our attention to sunstone’s unique hallmark—tiny particles of native copper metal that produce a glittering effect called schiller. “And then you have the intense schiller…When the sun hits it and it just pops out at you…you can’t even believe it!”

	Beautiful Gems, Pristine Location

	Owner John Woodmark introduces us to the Ponderosa Mine’s pristine location and explains how the gems from the mine mirror the natural beauty of the environment.

THE PONDEROSA MINING PROCESS
Woodmark is determined that we see all of the mine’s operations and witness the recovery of gem sunstone directly from the pit wall. We start right at the wall, which bears sets of deep, parallel gouges. He mentions this is the work of the “magic finger,” developed by a member of his crew as an attachment for their backhoe, and which makes mining much easier.

	Pickers scour their screens for the gleam of red sunstone. Photo by Robert Weldon.
He directs us to a rich red area of the pit wall. “In the rest of the mine, we only get about one-and-a-half to three percent red.” This patch, he asserts, is very different: “This area produces twenty percent red to the volume that we’re picking…so rich it’s incredible.”

Woodmark adds that the backhoe’s special attachment—basically a flattened metal spike—was the missing ingredient: “We haven’t monkeyed around with anything else since we got our ‘magic finger’ to break this stuff down. Before, it was too hard for our machines to work.”

Once enough of the pit wall is torn down by the backhoe, a small loader moves the ore onto an area of the pit floor. Next, the Ponderosa crew runs their massive forty-thousand pound loader over the material to crush it and loosen the stones.

The loader feeds the crushed rock through a dry trommel—a rotating screen that, with the harsh clatter of stone on metal, separates the dirt from the ore-bearing material. The next stage is a second trommel, this time using water. John tells us this piece of equipment takes the concentrate and “washes it, scrubs it, and knocks off a little bit of the volcanic crust that’s on the crystals.”

One load fills about twenty five-gallon buckets. The buckets quickly stack up behind each of the three screening stations set up at the time of our visit.

A picker stands behind each screen. Woodmark picks up a bucket of concentrate and pours the contents onto a screen to demonstrate for us: “We…throw all the big rocks off…spread it out fairly evenly…” He picks up a hose and directs a jet of water over the concentrate. “…then come back and spray it down.”

He pauses to pick up a choice piece of sunstone. “Nice red,” he observes. “And then we start…systematically going through the whole screen.” With a small trowel, he works methodically from one end of the screen to the other, telling us, “What we try and do is turn every stone…leave no stone unturned we tell the kids…so you start at one end and you just systematically turn every stone.”

	We recovered this nice specimen of zoned sunstone crystal in host basalt after it passed through the wet trommel. You can see that the crystal was originally considerably larger. Photo by Duncan Pay.
John’s diligence pays off with a small handful of rough sunstone, “You’ll get a handful like that off every screen…which probably weighs a few ounces.” He drops the red pieces into a plastic cup and tosses yellow or colorless rough into a bucket next to his feet. “They’ve got to go through a lot of screens to get a kilo…but like I say, they’ll pick about ten kilos on average per day.”

John emphasizes that speed is of the essence: It’s important to go through the screens quickly but accurately. “Don’t miss a thing, and get on to the next screen.” His rule of thumb is that the more screens you go through, the more you’re going to make: “I’ll do a screen every five-to-six minutes…it’s important not to jump around…because you’ll start to miss them.”

John’s eyes scan methodically from one end of the screen to the other, his trowel making quick movements to flip over the larger pieces: “A lot of our stones have a volcanic crust on them and even though they’ve gone through all the processes to get here, they’re very hard to find, so we go through it very methodically.”

“Don’t leave a stone unturned…” he admonishes us, “…because sure enough, there will be a red one hiding underneath there…and we don’t want to miss a red one.”

Once all the concentrate from a load is recovered, it’s washed for about an hour in a small cement mixer, which takes about 35 kilos at a time (60-70 pounds). “It’s almost like a rock tumbler…a giant rock tumbler,” Woodmark jokes.

When John tips out the mixer, there’s a crystalline glitter and tinkle as freshly washed rough cascades onto a small screen. “I’m looking for how many reds and how much schiller is in there…I’m looking for good stones that will bring money.”

He plucks out a limpid chunk of feldspar. “There’s a beautiful yellow…it’s a nice big size…see how clear and nice that stone is…that’ll make a terrific stone.” And then, a better prize: “Here’s a beautiful red…that’s going to make a tremendous faceted stone!”

The final step at the mine is to grade all this freshly cleaned concentrate. John leads us to a small table in front of the mine’s bunkhouse, where trays of sorted rough—reds, bicolors, schiller stones, yellows, and clears—rest in water-filled metal trays. The water cuts down reflections and helps with grading, he explains. There, in the shadow of tall ponderosa pines, John outlines the qualities a really fine gem might have: “The pinnacle is if it would be good enough to make a carving. A carving has to be something over 25 carats finished.”

He continues, “It has to have all the attributes…color…schiller…so it really is the pinnacle of an Oregon sunstone…We sell them for a lot of money…That’s just one in thousands of stones that we find.”

	Mining Sunstone at Ponderosa

	In this series, Ponderosa Mine owner John Woodmark explains how his crew goes about mining and processing, and grading rough sunstone.

NATIVE AMERICAN PICKERS
John is proud of his partnership with the local tribal outreach program, which started with five kids in 2006 and continues to the present. “We’ll pick for ten days at a stint,” John tells us. “After ten days, they’re burnt out picking stones and standing down there in the hot sun.”

	The Ponderosa partners with the local tribal outreach program to use Native American pickers. Photo by Jeff Jessing, Nature Revealed Photography, © 2009; courtesy of Desert Sun Mining Group
Unfortunately, at the time of our visit, there had been a robbery at the reservation and all the teens had left to assess the damage. However, each of us spent several hours working the screens, just as the pickers do. This gave us a very good concept of these kids’ “Ponderosa experience.”

	A lucky picker’s haul: A fine collection of “reds” decorate this screen. Photo by Robert Weldon
John outlines how his outfit houses, feeds, and pays the teen pickers: “For most of them it’s the most money they’ve ever had of their own…so the kids have all been absolutely great…they’re respectful, they’re glad to have a job, and all of us mentor them around the campfire.”

	A red crystalline glint in a scattering of red rock attracts this worker’s attention.
	Photo by Robert Weldon
To John, the amount of work he can provide hinges on the success of his business and, in turn, the popularity of sunstone with the jewelry-buying public. “The more sunstones we sell, the more people we can then hire,” he explains. “So if more people would get in behind Oregon sunstones, we’d have a lot more kids working here.”

	Employing Native American Teens

	The Ponderosa mine has an arrangement with the local tribal non-profit to provide work experience for Native American youth. The mine’s owner describes the benefits for both parties.

PROFIT
Woodmark is a savvy businessman, successful in many ventures before he acquired the Ponderosa mine. He applies the same financial acumen to sunstone as he would to any other commodity; “A kilo of red is worth twenty thousand dollars…we’ve got 25 of them in five days.”

	This choice piece of red sunstone rough will make a fabulous faceted gem. It’s just one piece in the 25 kilo haul the Ponderosa miners recovered during this trip. By Robert Weldon.
"We average 600 cut carats per kilo…an average price of 100 dollars per carat, I mean…is sixty thousand dollars…times 25…” He leaves us to do the math. “Yeah,” says Woodmark finally with a smile, “I think it’s pretty profitable!”

	Value of Rough Stones

	CEO John Woodmark explains the economics behind sunstone recovery at the Ponderosa mine.

THE GREAT ANDESINE CONTROVERSY
When we ask John about the andesine issue, there’s a hint of resignation in his answer. “Around 2004 or so, we started running into resistance because of a product out of China called andesine.” He explains that the jewelry channels jumped on it because every stone looked exactly alike, and as he puts it, “They could get them for nothing and sell them for a lot.”

Then for four years, while gemologists and geologists the world over tried to prove the authenticity or treated nature of this new gem, sales of Oregon sunstone were flat because people were afraid to invest. John is pragmatic on this topic: “We got hundreds of thousands of dollars’ worth of gemologists’ time and effort to prove that the andesine was a treated stone, but it also verified that Oregon sunstone was all natural.”

John contends that all the publicity over andesine was, in reality, a public relations blessing. “Nobody ever heard about Oregon sunstone before this andesine mess. Now everybody knows andesine was trying to be like an Oregon sunstone.”

In the three years since andesine’s treated nature was confirmed, John asserts his sales have increased year on year.

	Treated Andesine's Impact

	Recent issues with treated feldspar have impacted the market for natural Oregon sunstone. In this video, John Woodmark describes how his business was harmed, but also outlines some unexpected benefits from the affair.

SELLING SUNSTONE
Most consumers know about diamond, ruby, sapphire, and emerald, and might well favor those Big 4 gems. John understands it takes time and effort to open peoples’ eyes to sunstone’s unique attributes. “You have to sell an Oregon sunstone,” he says. “Most customers don’t know what it is.”

“The whole process of educating people and telling them about it,” he explains, “makes the stone personal.”

One of the qualities that make handling sunstone a challenge for commercial jewelry manufacturers—the uniqueness of individual gems might make them hard to match in jewelry—can play well with enlightened consumers looking for something different.

“We tell them about the uniqueness of having the copper particles in the stone, which makes their stone as unique as a snowflake,” John continues. Finally, he adds another set of strengths: “This is an American gemstone, picked by Native Americans…It’s only found in America, and it’s rare and exotic…so you know, it’s a terrific stone.”

	Educating Customers

	CEO John Woodmark explains his belief that the key to acceptance of sunstone as a mainstream gem lies in consumer education. Source: GIA @topic:1


Title: Tucson Visit Spurs Geology Professor, Publisher to Head Back to School Abstract: Dr. Hobart King, GG, began prospecting for invertebrate fossils in his parents’ limestone driveway as a 6-year-old and tumbling rocks a few years later. He enjoyed a long, established career as a geology professor before purchasing the website Geology.com. “Always be learning,” he says. “Keep your eyes open for new skills, tools, and information that can advance your business.” Courtesy of Geology.com. Photo by Bradley Cole

Dr. Hobart King was already an accomplished geologist with more than 40 years of experience, 20 of those spent teaching at the university level. He’d moved on to a career in publishing, but a casual visit to GIA’s informational booth at the Tucson gem and mineral shows led him back to the classroom – this time, as a student.
King, who worked as a geologist at West Virginia University and the West Virginia Geological and Economic Survey from the mid-1970s through the early 1990s, taught at Pennsylvania State University and Mansfield University of Pennsylvania from the 1980s through 2008. He taught geology, hydrology, global positioning systems and web-based cartography, and served as the director of Mansfield’s Center for Effective Teaching and a content advisor for the Earth and Space Science Education program.
When King approached the GIA booth in 2010, he had already started to consider furthering his own education. He had also begun publishing informational articles on Geology.com, an Earth science news and information website he purchased in 2005 with the intent to help educate the general public and those interested in introductory geology.

“Tumbled stones are the least expensive way to start a gem collection,” says King, who sells a few tons of the stones each year to hobbyists and beginning lapidaries, and even sends them to GIA for identification. “When I took GIA’s Gem Identification course, I was happy to be asked to identify a number of tumbled stones.” Courtesy of Geology.com. Photo by Bradley Cole
“I’d always been interested in gems,” he says. “As I wrote articles about rocks and minerals for Geology.com, many were gem materials, and I’d sometimes include a photo of a cabochon or faceted stone. I noticed the gem photos led to a large increase in visitors, so I started adding more information about gems to those articles. The popularity of those articles increased in page views and how much time they’d spend on the page – my visitors wanted to know about gems! That compelled me to obtain a formal education in gemology so I could write more competently.”
King had been an early adopter of online education, helping Mansfield University of Pennsylvania develop what he believes was “one of the first interactive geology courses in the United States delivered completely online.” He was surprised and pleased to learn that GIA offered Distance Education classes, and enrolled immediately in Colored Stones Essentials, continuing with other GIA Distance Education courses over the next several years.
In 2016, King had a personal breakthrough that made it possible for him to delve even deeper into the world of gemology: new vision.
“Cataract surgery dramatically improved the clarity of my vision and perception of color,” he says. “That motivated me to enroll in GIA’s lab courses, so I decided to take the Colored Stone Grading lab class while visiting California, and returned later for Diamond Grading and Gem Identification.”

King’s team, which works in publishing and e-commerce for Geology.com and RockTumbler.com, includes (from left): Bradley Cole, Amber Cole, King’s sister Laura Rittenhouse, Hobart King, and his daughter Angela King. Courtesy of Geology.com. Photo by Bradley Cole
King, whose interest in geology began as a 6-year-old “prospecting” for invertebrate fossils in his parents’ limestone driveway, earned his Graduate Gemology diploma in 2017 – 42 years after earning his first degree in geology.
“I’m convinced that GIA’s Gem Identification course is one of the finest – if not the finest – distance education course available,” he says. “The entire GG program has to be among the best programs delivered online, and it’s been an important asset for me. It is extremely helpful in my content writing, and provides a credential that separates me from writers who are not writing from formal education and experience.”
The continuing education has helped equip King and his four employees, including his sister and daughter, who also run a lapidary and rock tumbling retail site RockTumbler.com, to better serve the million-plus visitors that Geology.com draws every month.
“A typical visitor might arrive looking for information about rocks, minerals, volcanoes or maps – then, they see an article about a gemstone and read that,” says King, who considers writing educational content for them to be his most important job. “In a way, our website has become an ambassador for gemology, an applied form of mineralogy, one of geology’s core disciplines.”

“As in gemstones, the inclusions of mineral debris in coal is undesirable,” says King, a former geology professor and a GIA GG. “Evaluating coal is similar to evaluating the clarity of gemstones, the difference is mainly a matter of scale.” His image of a “highly magnified view of coal in transmitted light” shows a spore (large yellow object), thin shreds of woody material (red bands), smaller spores and algal debris (orange and yellow particles), and charcoal or opaque mineral inclusions (black material.) Courtesy of Geology.com. Photo by Hobart King
He’s found that researching and preparing Geology.com’s daily news page, for which he aggregates relevant news stories from trade and consumer media, takes the bulk of his work time while also attracting significant engagement from visitors.
“The daily news page is the part most visited by professional geologists, and they engage with stories related to oil, gas and mining,” he says. “Oil and gas, earthquakes, volcanoes and mining stories are the most popular with our overall readers. Knowing what they engage with guides me, and I include a sprinkling of other topics for curious visitors.”
King is fascinated by the “connections and patterns” he finds between news stories.
“With natural gas, for example, when I see topics surrounding discoveries, pipeline projects announcements and liquefied natural gas over a period of months, it helps me make connections and understand the movement of prices and global production, consumption, investment and politics,” he says. “And I hope my readers will see these patterns, too.”
As King has advanced in his own studies of gemology, he’s making connections between gem and jewelry news on JCK daily blogs, for example, and stories in Gems & Gemology and Mining.com.
“Retail, research and mining have many intersections,” he says.
King is endlessly curious, and hopes the accessible, educational content and introductory lapidary supplies his companies provide will inspire others to also develop eager, open minds.
“We learn something new every day,” he says, “and we’ll continue to share as we learn.” Source: GIA @topic:7


Title: Characterization of Peridot from Sardinia, Italy Abstract: Gem-quality peridot is occasionally found as mantle xenoliths within basalts near Pozzomaggiore, in northwestern Sardinia, Italy. The gemological properties and spectroscopic features of this material are consistent with the measured chemical composition of Fo91Fa9, typical of peridot from other localities worldwide. Although not yet mined commercially, this stone represents a promising gem material. Source: GIA @topic:2


Title: Natural Emerald with Inclusions Along Three Directions Abstract: Figure 1. This 10.48 ct sugarloaf emerald from Zambia shows a vivid and highly saturated green color. Photo by Yizhi Zhao.

Recently, Guild Gem Laboratories received a 10.48 ct sugarloaf emerald (figure 1) for identification and origin determination. The refractive index (approximately 1.58) and specific gravity (approximately 2.80) fell within the range for beryl, and Fourier-transform infrared (FTIR) testing confirmed it as natural emerald. Additionally, energy-dispersive X-ray fluorescence (EDXRF) analysis revealed Fe, V, and Cr contents consistent with those in Zambian material.

Figure 2. Platy inclusions in the emerald in three directions, intersecting at 60/120 degree angles viewed along the c-axis. Photo by Yujie Gao; field of view 2.8 mm.

Figure 3. Top: The hexagonal inclusions in the basal plane are parallel to the orientation of the platy inclusion described in figure 2. Field of view 3.1 mm. Bottom: A thin layer exhibiting growth lines is perpendicular to the emerald’s c-axis. Photos by Yujie Gao.
The stone showed interference colors when placed under a polariscope with the bottom facing up. With a conoscope, the optic axis of this emerald was determined to be perpendicular to the bottom. Using the microscope, we found thin platy inclusions arranged in three directions intersected with each other at 60/120 degree angles (figure 2). Those inclusions were mainly dark brownish and transparent with well-formed rectangular shapes, some of which exhibited a light bodycolor resembling an unhealed fracture. Evenly distributed reflective light could be seen at certain angles. We deduced that those inclusions had relatively smooth surfaces, which means that their original crystal faces were not corroded during the emerald’s formation. Further observation revealed hexagonal inclusions in the basal plane. Owing to uneven development during their crystalline formation, several of them were nearly triangular in shape. Their sides were parallel to the direction of the platy inclusions (figure 3, top). We also found distinct growth lines near the bottom of the sugarloaf perpendicular to the c-axis. These platy inclusions appeared to be concentrated sparsely in a thin layer with a thickness around 1.5–2.0 mm, as shown figure 3 (bottom). The sparseness of the oriented inclusions resulted in the absence of asterism or cat’s-eye phenomena.

Figure 4. Proposed illustration of hexagonal inclusions in the basal plane and platy inclusions along the prismatic faces. Illustration by Yujie Gao.
Considering the optic axis, we concluded that the platy inclusions grew along the hexagonal prismatic emerald faces, with the hexagonal platy inclusion parallel to the basal plane, as illustrated in figure 4. However, it is still unclear whether they were syngenetic or exsolution, since their well-preserved shapes showed little evidence of corrosion and there was insufficient evidence of exsolution. Source: GIA @topic:3


Title: GIA’s 2018 Symposium: Up and Away! Abstract: Since GIA’s first International Gemological Symposium in 1982, this event has served as a platform for advancing knowledge in the research and business sides of gemology. For three days, October 7–9, we celebrated the centennial of the incomparable Richard T. Liddicoat by hosting GIA’s sixth Symposium. Nearly 800 attendees from 36 countries gathered in Carlsbad, California, including more than 100 presenters and panelists.
We’ve prepared this special Symposium Proceedings volume of G&G to capture the insights and the spirit of this unforgettable event. Scenes from all three days and nights are shown in the photo montage scenes from all three days and nights are shown in the photo montage.
The Symposium experience began with a powerful opening session featuring The Music Paradigm. Audience members found themselves seated within a live symphony orchestra as maestro Roger Nierenberg offered dynamic lessons on leadership and teamwork. This performance was followed by an opening gala at GIA World Headquarters. On display at the campus were some extraordinary new exhibits assembled by the GIA Museum. This gala was the first of three evening social events for rekindling old friendships and creating new ones.
In the Symposium research track, 37 speaker presentations and 68 poster sessions covered seven important themes: colored stones and pearls, diamond geology, diamond identification, gem characterization, gem localities and formation, general gemology and jewelry, and new technologies and techniques. In the speaker abstracts and the poster abstracts, you’ll find a wealth of informative research summarized. An index of all the presenters appears in the back of the issue.
In a parallel program, classes taught by three professors from the Harvard Business School explored real-life case studies on authentic leadership, customer centricity, and disruptive innovation. Participants gained a deep understanding of these strategic concepts through classroom sessions and discussion groups.
The Symposium’s closing session, the Futurescape Forum, brought together six of the industry’s most influential leaders to forecast what lies ahead as technological breakthroughs, changing consumer tastes, and sustainability concerns continue to reshape the gem and jewelry landscape. You’ll want to read the recap of this lively and thought-provoking panel discussion.
This event would not have been possible without the thousands of hours of planning by the Symposium steering committee and the dedicated efforts of dozens of GIA volunteers, all of whom are recognized on the front and back inside covers of this issue. I am especially grateful to Kathryn Kimmel, GIA’s senior vice president and chief marketing officer, for once again chairing the Symposium and bringing to it her own signature style.
To all those who came to Carlsbad to attend the Symposium, we simply cannot thank you enough for being part of this event. We hope that you came away from it informed and inspired to embrace the future of our great industry. Source: GIA @topic:7


Title: Fall 2018 G&G: Proceedings from the 2018 International Gemological Symposium Abstract: The 2018 GIA International Gemological Symposium, held October 7–9 in Carlsbad, California, was the sixth such
event dedicated to groundbreaking research across the gem and jewelry industry. A number of presentations discussed
inclusions in gem materials. The cover photo uses differential interference contrast to show the interior scene
of a diamond, where localized areas of high solubility appear as dissolution trigons decorating twin planes in a linear,
crystallographically aligned arrangement. Photomicrograph by Nathan Renfro; field of view 0.83 mm.

In celebration of Richard T. Liddicoat’s centennial birthday, GIA held its sixth International Gemological Symposium October 7–9, 2018, in Carlsbad, California. Nearly 800 attendees from 36 countries convened to exchange groundbreaking gemological research and to examine case studies taught by professors from the Harvard Business School. The Fall 2018 issue of G&G is dedicated to the proceedings of the Symposium. Featured are 37 speaker abstracts and 68 poster abstracts from the research track’s seven themes: Colored Stones and Pearls, Diamond Geology, Diamond Identification, Gem Characterization, Gem Localities, General Gemology and Jewelry, and New Technologies and Techniques.
In Colored Stones and Pearls, keynote presenter Barbara Dutrow considered tourmaline’s role as a geologic timekeeper, while Wuyi Wang began Diamond Identification with the color origin and type Ib designation of canary yellow diamonds. The Diamond Geology session opened with Graham Pearson’s discussion of “unconventional” formation settings, while Evan Smith headlined Gem Characterization by examining the genesis of natural type IIa and IIb diamonds. Lee Groat’s keynote presentation in Gem Localities related the importance of “fingerprinting” chemical analysis to origin determination. In General Gemology and Jewelry, Saleem Ali explored the challenges and emerging opportunities—including education, beneficiation, and environmental remediation—in creating a sustainable mine-to-market colored gemstone supply chain. In New Technologies and Techniques, keynote speaker Daniel Twitchen reviewed advances in the chemical vapor deposition (CVD) process used to create laboratory-grown diamonds.
The poster presentations, on display and available for viewing by attendees for all three days, are also captured in this issue of G&G.
In the closing session, the Futurescape Forum offered an illuminating forecast from six influential leaders in the gem and jewelry industry. The panelists discussed sourcing and production, the online vs. brick-and-mortar store retail experience (including Internet vs. in-person auctions), the impact of laboratory-grown material on the diamond market, and adapting to a millennial workforce.
The Fall 2018 issue also contains a photo montage with scenes captured during the Symposium, from the Music Paradigm opening session to the farewell reception. Source: GIA @topic:7