Publish Year: 2016 Title: Responsible Mining, a Trek to Chivor, and a Dash of Fabergé Abstract: The quest for gem-quality natural diamonds is a multi-billion-dollar enterprise—and a stern test of human ingenuity. Any investment in a large, modern mine is by necessity strategic, and made all the more complex when the location is remote and subarctic. Thus it is with the Diavik mine, which sits on a small island on pristine Lac de Gras in Canada’s Northwest Territories. Replete with engineering challenges, and the need to accommodate the concerns of the area’s indigenous people, Diavik’s transition to an active mine in 2003 is a landmark development in the fascinating story of Canadian diamonds.

	Our lead article, by Jim Shigley, Russ Shor, Pedro Padua, Mike Breeding, Steve Shirey, and Doug Ashbury, offers a review of this mine’s discovery, development, and operations and looks to its planned closure in 2024, when the site will be restored to nearly its original condition. Besides its value as a premier gem diamond source—100 million carats and counting—Diavik is a tantalizing window for geologists into the depths beneath the Canadian Shield. Knowledge acquired from the kimberlites at Diavik allows geoscientists to reconstruct the early history of the North American continent and underscore the supreme value natural diamonds hold for science, beyond their monetary worth as gems.

		A landmark development in the fascinating story of Canadian diamonds.

	In addition to Diavik, we offer articles on a pair of exquisite Fabergé figures, the current state of the colored gem industry’s supply chain in terms of corporate social responsibility, the fashioning of an exceptional Australian opal, and a trek to Colombia’s Chivor emerald mine in the footsteps of its remarkable manager, Peter W. Rainier.

	Our second paper, by Tim Adams and Christel Ludewig McCanless, presents two rare Fabergé hardstone figures depicting the Romanov empresses’ Cossack bodyguards. It discusses the design, construction, and subsequent history of the pieces since their creation using Russian-mined gems and metals in the firm’s St. Petersburg workshop.

	Next, Jennifer-Lynn Archuleta reviews ongoing efforts to establish ethical, sustainable mine-to-market supply chains within the multibillion-dollar colored gem industry. She outlines the challenges the industry faces on its journey to toward greater transparency and traceability in a climate of heightened scrutiny from NGOs, governments, and concerned consumers.

	In our fourth paper, Ted Grussing reveals the special considerations he applied to cutting a 3,019 ct gem-quality white opal from Coober Pedy, Australia. He describes how care and attention to detail maximized size and quality, yielding a 1,040 ct finished gem with play-of-color across its entire surface.

	Finally, join Robert Weldon and his co-authors on a journey through the early twentieth century history of the Chivor emerald mine and revisit the achievements from a productive and colorful era in Colombian emerald mining.

	As always, you’ll also find plenty of interesting content in our latest Lab Notes, Micro-World, and Gem News International sections. And don’t forget to visit www.gia.edu/gems-gemology for exclusive photos and videos from this issue.

	We hope you enjoy our Summer issue! @topic:2


Publish Year: - Title: Baselworld 2016: Spotty Demand; Glitz Out, Rare In Abstract: Lighter traffic and less bling summed up Baselworld 2016. Photo by Russell Shor/GIA

	Distinctiveness reigned over bling at the Baselworld show in Switzerland. Traffic was down and business spotty at the March 16-23 show, though a number of exhibitors said demand had improved from last year.

	The smart sellers adapted to a changed market, offering the rare, unusual and distinctively designed in place of (or in addition to) high carat weights for their own sake.

	Exhibitors noted that buyers were looking for jewelry, not investments which require buyers to pay for gemstones with devalued currency, making a profitable resale very difficult. In previous years at the show, sellers of large diamonds estimated that at least one-third of all diamonds larger than 5 carats were bought for investment, not jewelry.

	Indeed, for years, sellers of large, high-quality diamonds and colored gemstones at the Baselworld fair could count on brisk demand from a diverse group of private clients, largely from Russia, China and the Middle East.

	Demand for such stones has slowed considerably for the past two years at the show, however, because of a confluence of events: a concerted crackdown of large cash transactions; a rising U.S. dollar that raises the costs of these goods by 10% to 40% in other currencies; economic slowdown in China and other previously fast-rising economies; and depressed prices for oil and other commodities.

	Colorless diamonds larger than 5 carats were a difficult sell at the show. As one dealer of major stones put it: “Very few buyers from Russia and the Middle East were here − they used to account for a lot of the high-ticket demand.”

	The dealer did say that prices for top stones have not softened as they had for more commercial diamonds because most dealers have the financial capacity to hold on to them until demand improves. Additionally, unlike the commercial diamond market, buyers of large diamonds rarely try to save money by down trading quality.

	“They either want the best, or will not buy,” he said.

	Demand for commercial-sized diamonds did pick up at the show and the market in general. One reason is that prices have fallen to levels where, as one exhibitor put it, “manufacturers and their clients now want to do business.”

	He added that the “green shoots of recovery” are buoying the diamond market, but it remains fragile. “We have to worry whether the mining companies will raise prices again, whether China’s economy has truly hit the floor, whether the problems in major European banks will bring another downturn and whether terrorism and refugees will disrupt the world economy. It’s a lot to worry about, but we must stay optimistic.” The March 22 terror attacks in Brussels, about 350 miles north of Basel, prompted city police and fair management to conduct random searches of attendees’ briefcases and bags and limit access to the show to the front entrances.

	This necklace of 28 “apple green” Namibian demantoid garnets totaled 128 carats. It was offered by Paul Wild of Idar Oberstein, Germany. Please note: this photo was taken using a mobile phone under harsh lighting conditions. Photo by Russell Shor/GIA

	Demand for colored stones was extremely selective. Buyers were looking for extremely fine Burmese rubies, no-oil Colombian emeralds and rarer stones like Kashmir sapphires.

	“The ultra-wealthy now want exceptional stones they can get nowhere else,” said one dealer. “But the demand for stones in the $20,000 to $50,000 range is vanishing. The trouble is, once you sell these unique stones, it’s almost impossible to replace them.”

	One dealer was showing a Namibian demantoid garnet necklace with 28 round cuts totaling 128 carats (cts.). The dealer said it took eight years to assemble, particularly because the color of each stone was apple green instead of the customary olive color and, because very few 2-ct. plus demantoids of that color are mined each year.

	Another dealer displayed a 50.09 ct. purple-to-violet color-change sapphire from an estate, which, he claimed, sparked a lot of interest and a pearl dealer offered a 20.48 mm x 23.21 mm drop shaped South Seas cultured pearl.

	This 50.09 ct. color-change, purple-to-violet sapphire offered by Pioneer Gems of New York, was one of the rare and unusual gemstones on offer at Baselworld. The sapphire, set in a ring accented with colorless diamond melee, came from an estate. Please note: this photo was taken using a mobile phone under harsh lighting conditions. Photo by Russell Shor/GIA

	The high-end jewelry houses and luxury watch companies that debut their products at the fair put their focus more on design and less on the gem-covered look of a few years ago.

	“Fewer diamonds, strategically placed for maximum show,” is how Chopard put it for their new “Happy Diamonds” watch line. This line had four 5 millimeter (a bit less than 0.5 cts.) diamonds floating inside the watch dial. The focal point was on craftsmanship and design said the company.

	This 5.03 ct. synthetic Fancy Deep blue diamond was on display at Baselworld by New Diamond Technologies of St. Petersburg, Russia. The company claims it is the largest synthetic blue diamond created by the HPHT process. Photo by Russell Shor/GIA

	Even Laurence Graff, known for some of the costliest diamond jewelry in the world, took a step back from ultra-bling to create a more modest line of sapphire and diamond watches in its “Butterfly” collection.

	Swiss watch makers reported that exports of luxury watches made there declined nearly 8% during the first two months of the year, largely because of a 33% decline to Hong Kong (continuing a year-long slide), where the Chinese slowdown has hit hard, and 13.7% fall in sales to the U.S., where ostentatious luxury is falling out of favor.

	Also at the show, a Russian synthetics manufacturer displayed a 5.03 ct. Fancy Deep blue it claimed to be the largest blue diamond ever grown by the HPHT process. The company said it took much more than a week to grow and is in the process of creating additional synthetic blues. @topic:7


Publish Year: 2011 Title: Brownish Red Zircon from Muling, China Abstract: Gem-quality brownish red zircon occurs in alluvium derived from Tertiary alkali basalt at Muling in the northeast Chinese province of Heilongjiang. Rough and cut samples were characterized using standard gemological methods, electron microprobe, LA-ICP-MS, and Raman and UV-Vis-NIR spectroscopy. Internal features consisted of melt inclusions, apatite, magnetite, fluid inclusions, and color zones. The samples contained abundant rare-earth elements, but showed only slight radiation damage and properties consistent with “high” zircon. Although it has yet to be mined commercially, the Muling deposit is a promising source of gem zircon. @topic:3


Publish Year: 2016 Title: Dolomite with Unusual Inclusions Abstract: These brownish orange cubic to rhomb-shaped inclusions were identified by Raman analysis as svanbergite in dolomite. Photomicrograph by Jonathan Muyal; field of view 14.52 mm.

	Dolomite is not often encountered as a gem material, and it is generally known as an inclusion in gems such as emerald, garnet, quartz, and ruby. In view of this, any inclusions found within gem-quality dolomite may be justifiably considered as rare inclusion/host combinations.

	One particular area known to produce gemmy dolomite suitable for lapidary work is the Mount Brussilof mine in Radium Hot Springs, British Columbia, Canada. Also found at this mine in direct association with the dolomite are crystals of the relatively rare mineral svanbergite.

	Crystallizing in the trigonal crystal system in a rhombohedral to pseudocubic habit, svanbergite is not a widely known mineral associate of dolomite or any of the other common carbonates. It is a member of the beudantite mineral group and is composed of basic phosphate and sulfate of strontium and aluminum phosphates and sulfates. Svanbergite colors range from reddish brown to orange; there is also colorless material.

	Recently we had the opportunity to examine a cluster of inclusions surrounded by numerous tiny fluid inclusions within a colorless gem-quality dolomite. It came as a delightful surprise when laser Raman microspectrometry revealed these crystals to be svanbergite, an inclusion-to-host pairing we’ve never previously encountered. @topic:1


Publish Year: 2016 Title: Tucson 2016 Abstract: Figure 1. Tucson’s GJX show saw considerable traffic this year, including a higher number of American buyers. Photo by Andrew Lucas.

	For decades, buyers and sellers from every aspect of the gem and jewelry industry have flocked to the gem fair in Tucson, a town in the heart of Arizona’s Sonoran Desert that is rich in cultural and natural heritage. The annual shows are widely considered a forecast for the rest of the year. While the shows of the past few years have reflected a sluggish industry, the atmosphere in 2016 was dramatically different, with an increase in both attendance and business. The 34th AGTA GemFair saw record pre-registration numbers, and more than 300 exhibitors greeted a full house of buyers on the opening day. Gabrièl Mattice of Pala International (Fallbrook, California) said that sales were very strong this year, even on the first day of the show. The energized interaction between exhibitors and buyers was evident throughout the convention center. Though diamond sales have slowed, colored stones have gradually gained momentum among jewelry customers, and designers are responding in kind. Although the overall market share for colored stones is still small compared to the diamond sector, efforts to promote them have had very positive results.

More Serious Buyers. After the surge of foot traffic on the opening day, attendance remained stable at the shows for the rest of the week (figure 1). Vendors saw fewer Chinese buyers than in 2014, though Josh Saltzman of Nomad’s Co. (New York) indicated that those who came were serious buyers picking up high-quality goods. Gaurav Shah from Real Gems Inc. (New York) confirmed that his company has seen greater demand for emerald in mainland China since 2007, a market that slowed in 2015. He said that the Chinese are more cautious and specific in their purchases, and he predicted an upswing in Chinese buying activity in the near future. Joseph Nakamura of Shogun Pearl (White Plains, New York) said that 95% of his customers were from the United States, while Gabrièl Mattice also saw many Europeans on the floor, especially French buyers. Many new buyers attended, possibly due to the stabilized prices and heightened interest in colored stones (figure 2). Mr. Shah observed three categories of clients in Tucson: buyers from television and Internet companies, retailers, and designers.

Figure 2. A customer examines some calibrated emeralds at the Real Gems booth in the AGTA show. Photo by Tao Hsu.

	David Bindra of B&B Fine Gems (Los Angeles) noted that the number of transactions relative to the attendance was much higher than in previous years. He felt that this year’s AGTA show was much better than the September 2015 Hong Kong Jewellery and Gem Fair, where many sellers felt the slowdown of the mainland Chinese market.

Calibrated Goods. Though high-end colored gems continue to set auction records, the market for these stones remains slow. As a result, the colored stone trade still mainly consists of goods in standard calibrated sizes rather than custom-cut material (figure 3). Many cutting factories are able to provide a greater selection of sizes that fit their clients’ requirements. This especially benefits the jewelry manufacturers in China and India, as setting calibrated gems is the bulk of their workload. Thus, mid-priced colored goods were the overall best sellers in Tucson. Nirmal Bardiya of RMC Gems (Bangkok) informed us that calibrated goods of various millimeter sizes are best sellers in the American market, while Arthur Groom Jr. of Eternity Natural Emerald (Ridgewood, New Jersey) noted that Afghan emerald melee is one of his biggest sellers. Guarav Shah reported that the most popular calibrated cuts are oval, emerald, and pear shapes; these goods generally range from $200–$2,000 per carat.

Figure 3. Assorted goods in calibrated sizes sold very well at the shows. Photo by Tao Hsu.

Classics. No single stone stole the show this year. Some relatively new varieties were available, but their potential is still hard to evaluate. Some people asked about the color-change pink pyrope garnet that has recently been covered by multiple trade magazines, including the Winter 2015 G&G. Ms. Mattice said it will take time to educate people about this stone, and it is not easy to predict the market potential. Mr. Bardiya informed us that morganite (figure 4), aquamarine, and blue topaz were popular among RMC’s American clients. According to Joseph Nakamura, white pearls still dominate, while other colors come and go with different fashion trends. According to multiple dealers, Paraíba tourmaline is still in high demand (figure 5).

Figure 4. Morganite attracted many American buyers this year. Photo by Andrew Lucas.

Figure 5. According to many exhibitors, Paraíba tourmaline remained one of the shows’ best sellers. Photo by Andrew Lucas.

	Even so, the “big three” of ruby, sapphire, and emerald still dominate the market and fetch higher prices, which was reflected in this year’s shows. Corundum is still the most popular material in the high-end sector. David Bindra and Gabrièl Mattice both said that sapphires sold very well, and Mr. Bindra thinks that blue and green material will be especially strong this year, though yellow sapphires drew more interest than at previous shows. Pink and pastel-colored sapphires also attracted many buyers, perhaps because they evoke rose quartz and serenity blue, Pantone’s colors of the year for 2016.

Interest and Demand for Color. As one of the best platforms to trade and promote colored gemstones, the Tucson shows provide buyers with the finest goods sourced from all over the world. Some one-of-a-kind stones debut here, such as the 332.24 ct Imperial Flame topaz carving. Spectacular stones such as these usually attract immediate attention.

	Mr. Bindra tied the increase in sales to a growing awareness of colored stones. Once-daunted consumers are becoming more knowledgeable about different varieties and are better prepared before they purchase. This interest in learning was reflected at the AGTA GemFair seminars, which saw a 30% increase in attendance.

	Greater appreciation for colored stones motivates designers and retailers to source more of them (figure 6). Mr. Shah did business with more designers than in previous shows. The authors themselves saw materials in more unique cuts that seemed intended to capture the designers’ imagination (figure 7). Mr. Shah said that even though Real Gems is a wholesaler, the company does not have a minimum order requirement for any buyers. This is very helpful for many designers, especially the young ones. This exhibitor feels that it is worthwhile to do business with people who are willing to work with and promote colored stones in their own work.

Figure 6. Colored stone jewelry is becoming increasingly popular among consumers, as designers such as Paula Crevoshay use colors in more creative ways. Photo by Tao Hsu.

Figure 7. Some pieces offered excellent options for designers who wish to create a unique look. Photo by Tao Hsu.

Summary. Based on their own observations, the authors were not surprised to hear vendors say that this was one of the strongest Tucson shows in recent history. People were encouraged by the renewed momentum of the American market, even though high-end buyers were still cautious. Relatively stable prices also contributed to increased sales, although the price of sapphire, ruby, and emerald remained high. With the positive forecast from Tucson, the trade is expecting a prosperous 2016.

	We thank the many exhibitors who provided insight, photos, and materials. @topic:11


Publish Year: 2016 Title: Tucson: A Showcase of Colored Gemstone Innovation Abstract: Welcome to 2016’s first Gems & Gemology!

	The Tucson shows are renowned for showcasing nature’s finest gems and minerals. They’re also the venues to see imaginative use of gem materials in unfamiliar combinations. Our cover exemplifies this innovation with the “Wheel of Light”—a spectacular necklace featuring elements of sagenitic quartz, fire agate, Paraíba tourmaline, and braided leather, centered on a clear quartz disk wrapped with 24K gold. The rough gems and minerals placed inside the disk’s central axis reflect within the quartz to produce strikingly colored concentric bands. This piece amply demonstrates the ingenuity that makes the Tucson gem and mineral shows such refreshing and vital experiences. We hope you find this issue equally enjoyable.

	We offer five feature articles on diverse topics: photoluminescence (PL) spectroscopy, Australian chrysoberyl, Italian serpentine, Tajikistan’s variscite, and treated “pistachio” cultured pearls from Tahiti. You’ll also find our latest Lab Notes and Micro-World entries, along with in-depth coverage of the February 2016 Tucson shows in our Gem News International section.

	Drs. Sally Eaton-Magaña and Christopher M. Breeding of GIA’s Carlsbad lab are the authors of our lead article, which provides an overview of PL analysis and its increasing importance for detecting treatment, determining natural or synthetic origin, and verifying origin of color in type II diamonds. PL spectroscopy is now a vital tool for gemologists to authenticate the most valuable large or fancy-color gems.

		Photoluminescence spectroscopy is now a vital tool to authenticate the most valuable diamonds.

	In our second paper, a team of researchers led by Dr. Karl Schmetzer characterizes the gemological properties and growth structures of chrysoberyl recovered from the sapphire placer deposits in New South Wales, Australia.

	Two other articles cover ornamental gem materials: First, Dr. Ilaria Adamo and colleagues offer a detailed mineralogical and gemological investigation of serpentine with gem potential from Pizzo Tremogge in Val Malenco, Italy. Next, Dr. Andrey Litvinenko and his coauthors report on a largely untapped source of the ornamental mineral variscite in central Tajikistan.

	Finally, Dr. Chunhui Zhou and his team from GIA’s New York lab document the identification of treated pistachio-colored cultured pearls produced by the Ballerina Pearl Co.

	We also offer hearty congratulations to the winners of the 2015 Dr. Edward J. Gübelin Most Valuable Article Award. We’re delighted with the fantastic response to our reader ballot, which showed a significant increase in participation over last year—a big “thank you” to everyone who voted. Also, don’t forget to take this year’s G&G Challenge, our annual multiple-choice quiz.

	Please enjoy the Spring issue! @topic:8


Publish Year: - Title: An Inside Look at the 2015 Tucson Shows Abstract: Many sellers at Tucson were displaying very large, fine, or unusual gems that had been held in inventory for years. Photo by Duncan Pay/GIA; courtesy of Noor Gems Japan Ltd.

                      Every year in February, colored stone miners, dealers, cutters, and retailers from around the world converge at the several major gem and mineral shows in Tucson, Arizona. In 2015, GIA once again interviewed industry professionals who presented spectacular gems and provided revealing insights on the global market. Links to these interviews are listed below.

New Production of Brazilian Emerald from Minas Gerais – Tucson 2015
Marcello Ribeiro of the Belmont mine showed emeralds from Belmont’s underground mine, including one especially fine 9.22 ct stone. As a GIA team visited Belmont in April 2014, it was interesting to see the gems from this relatively new part of the mining operation for sale at the show.
Learn More

Exceptional Red Spinels and Fine Aquamarine – Tucson 2015
Axel Henn of Idar-Oberstein, Germany, showed superbly colored 61.29 ct Tanzanian red spinel, including two pear-shaped gems cut from similar rough, and a spectacular 450.08 ct aquamarine with pure blue "Santa Maria" color.
Learn More

Fine Tsavorite and Spinel – Tucson 2015
Bruce Bridges of Tsavorite USA Inc. said that fine stones often return to his inventory after years in a collector’s possession. At the AGTA show, he showcased a vivid, top-quality 12.46 ct cushion-shaped tsavorite fashioned some 15 years earlier, which made its way back into the market in the last two years.
Learn More

Fine Corundum, Demantoid Garnet – Tucson 2015
Dave Bindra of B&B Fine Gems showcased fine pink and yellow sapphire, Mozambique ruby, and a superb suite of Russian demantoid garnet. He explained how increased consumption in markets outside the U.S. and Europe is affecting gem supply and forcing many colored gem dealers to turn to the “recirculated” market for their clients.
Learn More

High-End Colored Gems – Tucson 2015
Idar-Oberstein’s Constantin Wild displayed a unique 290 ct multicolored suite of specimen-quality gems from all over the world, rare “canary” tourmaline from Zambia, fine rubellite from Brazil and Nigeria, and an array of sets aimed at enterprising jewelry designers and manufacturers.
Learn More

Tsavorite Garnet and Mahenge Red Spinel – Tucson 2015
Daniel Assaf of the Tsavorite Factory provided a detailed market update for tsavorite garnet. In this interview, he explains how unprecedented Asian demand for this rare gem has drastically affected availability and pricing for his customers.
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Oregon Sunstone Update – Tucson 2015
Reviews the Oregon sunstone seen at the Tucson gem shows, provides an update of the current market and demand for the gem, and explains an initiative to set up an Oregon sunstone miners’ association.
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Large and Unusual Gems – Tucson 2015
The inventory of Noor Gems Japan Ltd. was characterized by large and unusual gems, including a fine selection of rare blue and pink gemstones: afghanite, hauynite, hemimorphite, and pezzottaite.
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Ginger Garnet, “Fancy” Tanzanite – Tucson 2015
Kobi Sevdermish of Advanced Quality introduced a new pinkish orange to orangy red “ginger” garnets that remains bright in larger sizes. He also outlined the trials and tribulations of sourcing and cutting the unique “fancy” tanzanite crystals his company specializes in.
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Gem Artistry in Smaller Sizes –Tucson 2015
Alexander Kreis displayed his most recent designs: tourmalines in organic fluid shapes resembling the leaves in a tropical forest, citrines evoking the essence of sunrays, and icy blue topaz that mimic the cool brilliance of arctic ice.
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Larger Optic Disks –Tucson 2015
Brian Cook of Nature's Geometry explained the latest step in the evolution of his innovative "wheel of light" optic disks: larger pieces that display more intriguing reflective effects, including a striking rainbow of concentric color bands.
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Unusual Carved Tourmaline Suite – Tucson 2015
Jan Goodman had an exquisite 303 carat suite of particolored tourmaline depicting Snow White and the Seven Dwarfs, carved in Idar-Oberstein in the 1970s and kept in his personal collection for more than 30 years.
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Gemstones and Jewelry Inspired by Nature – Tucson 2015
Award-winning cutter and designer Jeff Bilgore exhibited two pieces that departed from the norm of colored stones: an exquisitely carved leaf brooch of moss agate highlighted with diamonds, and a platinum pendant panel and chain featuring natural-color fancy diamonds that appeared to float within the frame.
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Rare Stones in Demand – Tucson 2015
Coast-to-Coast’s Brad Wilson explained that rare gems also have a place in jewelry. Innovative designers seek out rare materials such as sphalerite, sphene, apatite, and even afghanite for clients who appreciate the unusual.
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Color-Change Garnets from Tanzania – Tucson 2015
Introduces striking color-change pyrope garnets from Tanzania. Originally thought to be rhodolite garnets when found in the 1980s, these gems turned out to be predominantly pyrope, and the best examples show a strong red-to-purple color change.
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Bold Color Combinations – Tucson 2015
For retailers and designers overwhelmed by the endless rows of gemstones lined up in trays, inspiration could be found at the booth of Stephen M. Avery, which featured brightly colored "statement"-sized gemstones.
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Chrysocolla in Quartz – Tucson 2015
The Rare Earth Mining Company booth displayed a specialized inventory of unique and rare materials, including clear and near-colorless quartz containing blue spots of chrysocolla.
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Cultured Pearl Market Update – Tucson 2015
Fran Mastoloni provided a market summary from his own business perspective. He emphasized surging demand in the Chinese domestic market for all cultured pearl types, plus the need to introduce innovative styles and pearl combinations in contemporary jewelry.
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Chinese Freshwater Pearl Culturing, Overall Market Summary – Tucson 2015
Jack Lynch offered his perspective on Chinese freshwater cultured pearl products and styles, as well as fine South Sea and Tahitian goods.
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Diamond Slices – Tucson 2015
The popularity of gem slices, particularly diamond, is on the rise, as reflected at the 2015 Tucson gem shows.
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Large Namibian Demantoid Garnet – Tucson 2015
The Green Dragon mine yields exceptional demantoid, including a round brilliant seen at Tucson’s GJX show.
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Green Nephrite Jade Attracts Buyers in Tucson – Tucson 2015
An update on the nephrite jade market from the 2015 GJX show.
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Baroque Pearls – Tucson 2015
Baroque pearls were ubiquitous at the Tucson 2015 gem shows.
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Crimson Prince Ruby from Namya – Tucson 2015
An exceptional ruby is discovered in Namya, Myanmar.
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Update on Rock Creek Sapphire Deposit – Tucson 2015
An overview of recently expanded sapphire production at the Gem Mountain mine near Philipsburg, Montana.
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Unique Tourmaline Necklace – Tucson 2015
An unusual parti-color tourmaline necklace and clasp are seen at the 2015 AGTA show in Tucson.
Learn More @topic:11


Publish Year: 2009 Title: Ruby and Sapphire Production and Distribution: A Quarter Century of Change Abstract: During the past 25 years, the corundum market has been transformed from one of medium to high-priced gems to one that encompasses nearly all price ranges. This transformation was caused by the discovery of a number of large deposits and the development of treatment processes that enhanced the color and clarity of huge quantities of previously noncommercial sapphire and ruby. More recently, however, controversial treatments have undermined confidence and prices in some material, while political events and press scrutiny have affected the supply chain for rubies and sapphires from localities such as Myanmar and Madagascar. @topic:9


Publish Year: 2015 Title: Garnets, Sapphires, Opals, and Tarnish on High-Purity Gold Abstract: Amethyst purple under fluorescent equivalent lighting, hot pink under incandescent…

	Welcome to the final Gems & Gemology of 2015. Colored gems—garnet, sapphire, and opal—are prominent in this issue. The Tanzanian garnet on our cover projects a rich, bold pink and demonstrates just how fine this material can be. It’s profiled in our lead article. The issue also offers insight into the origin of Montana’s alluvial sapphires, a gemological study of the historic Grand Sapphire, an investigation into tarnish spots on high-purity gold, and a field report on Australian opal.

	Our first paper—by three of GIA’s young research scientists, Ziyin “Nick” Sun, Aaron Palke, and Nathan Renfro—examines interesting “color-change” pyrope garnet from Tanzania. Under fluorescent-equivalent lighting, larger gems have the color of fine purple amethyst, while under incandescent they resemble hot pink tourmaline. The authors provide a comprehensive review of this material’s inclusions along with a quantitative analysis of its color under different lighting conditions.

	Alluvial sapphires from the U.S. state of Montana have long been celebrated for their kaleidoscope of colors, but so far no one has located these gems’ primary source rocks. In our second paper, a team of researchers led by Dr. J.C. “Hanco” Zwaan focuses on mineral inclusions and geochemistry to propose a metasomatic origin for Montana’s alluvial sapphires.

	Next, Dr. François Farges and his colleagues profile the fascinating history and gemology of Louis XIV’s 135.74 ct Grand Sapphire, which was added to the French crown jewels in 1669, around the same time as the fabled Tavernier Blue diamond. On the basis of microscopic examination and spectroscopy, the authors suggest that this magnificent blue sapphire originated in Sri Lanka’s gem fields.

	Our fourth paper investigates unsightly tarnish spots in high-purity (99.9% Au) gold jewelry. Dr. Taijin Lu and his team from the National Gems & Jewellery Technology Administrative Center (NGTC) in Beijing use a combination of advanced techniques to detect the presence of silver and sulfur in the tarnish spots. The authors recommend careful cleaning during the gold manufacturing process to eliminate the possibility of silver contamination.

	In June 2015, a GIA team consisting of Tao Hsu, Andrew Lucas, and Vincent Pardieu visited four important opal fields at the rugged fringes of Australia’s arid Great Artesian Basin: Lightning Ridge, Koroit, Yowah, and Quilpie. Their field report documents mining activity and the growing importance of the revenue and employment brought to these remote outback communities by “opal tourism.”

	As usual, you’ll find our regular Lab Notes and Gem News International sections along with the third installment of the Micro-World column. Our GNI section includes an update from field gemologist Vincent Pardieu on rubies from a new deposit in Zahamena National Park, Madagascar. There are also reports from the 2015 Geological Society of America (GSA) annual meeting in Baltimore, the first International Emerald Symposium in Bogotá, Colombia, and the 34th International Gemological Conference (IGC) in Vilnius, Lithuania.

	Finally, you’ll notice this issue includes a ballot card for the Dr. Edward J. Gübelin Most Valuable Article Award. We had a fantastic response to our 2014 reader ballot, so please do vote again for your favorite 2015 articles.

	Please enjoy the Winter issue! @topic:2


Publish Year: - Title: Romancing the Source: Pakistan Abstract: Pakistan

	Pakistan’s portion of the Silk Road traverses some of the highest mountains in the world, where mining benefits locals and helps them rebuild their lives.

	This series of articles and videos follows a team of GIA Field Gemologists on their travels from the mountains of Afghanistan to the jungles of Sri Lanka in search of the sources of colored gemstones and the people who pursue them. This thrilling journey will take you to remote gemstone-mining areas, where you’ll witness the extreme effort required to wrestle nature’s treasures from the earth.

	The romance of a colored gemstone arises from its beauty, the exotic qualities of its source’s location, the adventure leading to its discovery, and the stories of the people who seek it. These factors have united to create the allure of gemstones through the ages, and continue to do so even in modern times.

The northern region of Pakistan is home to some of the world’s highest mountains. In a ruby-producing area near the beautiful Hunza Valley, this miner’s wife attends a program created to educate her children and teach her to cut gemstones. Photo by Andrew Lucas.

	Pakistan yields a wealth of gemstones for jewelry and for mineral collectors. Incredible crystal specimens from the areas around Skardu, ruby from the Hunza Valley, and emerald from the Swat Valley are a few of the area’s treasures.

	Reaching the Gilget/Hunza valley area can involve a 17-hour drive from Islamabad, as flights are often cancelled due to weather conditions in the mountains. The drive is on the Karakoram Highway that passes through the area where three of the world’s greatest mountain ranges meet: the Karakoram, Hindu Kush, and Himalaya ranges. The dramatic forces created by the collision of these mountain ranges led to geological events that formed gemstones and shaped the area’s rugged terrain. This highway is part of the old Silk Road, and traveling on it today is still an exhilarating experience.

	The Swat Valley has been called the Switzerland of Central Asia. It’s surrounded by beautiful mountains covered with snow in the winter. After a violent conflict between Pakistani military forces and Taliban militants that led to the overthrow of Taliban control, emerald mining resumed in the valley as a means to rebuild the area and people’s lives. @topic:9


Publish Year: - Title: Summer 2015 G&G: Dual-Stars, Photomicrography Guide, Rubies from Tajikistan, New Micro-World Section Abstract: Nathan Renfro’s article in this issue explores the role of image-processing software and lighting techniques in modern digital photomicrography. The cover image shows modified trigons on the surface of a diamond crystal from the Kelsey Lake mine on the Colorado-Wyoming border. This Nomarski differential interference contrast image was taken using a Nikon Eclipse LV100 microscope equipped with a 20× objective and a Canon 6D camera. Helicon Focus stacking software was used for extended depth-of-field image processing of 70 photomicrographs into a single image. Vertical field of view: 0.49 mm. Image by Nathan Renfro.

	Stars are one of the most fascinating phenomena in the gem world, and the summer issue of Gems & Gemology (G&G) takes an extensive look at the cause of dual-color double stars in both corundum and quartz. The issue also offers gemologists a how-to on taking photomicrographs of gemstone inclusions and a view of the rarely visited ruby source at Snezhnoe, Tajikistan. In addition, G&G debuts a new section called Micro-World, which offers a deep look inside gemstones to examine inclusions and the gems’ “inner-space.”

Dual-Color Double Stars in Ruby, Sapphire, and Quartz: Cause and Historical Account

Dual-color double star ruby and sapphire are best known from a line of synthetics mainly produced by the Linde Air Products Co. for the fashion jewelry market for nearly 30 years. Such stones are also occasionally found in nature in different sources around the world. The dual color refers to the double stars, one of them white and the other matching the host stone’s body color.

This pink synthetic sapphire showing a white six-rayed star and a pink star was purchased by one of the authors in Bangkok in 2010. The cabochon measures 14.4 × 11.2 mm and weighs 12.37 ct. Photo courtesy of M.P. Steinbach.

	In addition to the synthetics by Linde, the authors (Karl Schmetzer, Martin Steinbach, H. Albert Gilg and Andrea Blake) examined natural purple-pink sapphires from Myanmar, recently manufactured synthetics from various sources, and natural quartz from India and Brazil that also displayed the phenomena.

	The researchers noted that the customary white star is caused by minute rutile needles that reflect and scatter light at the surface of the curved dome of the cabochon. The body color star is also caused by these rutile inclusions, which reflect and scatter the light emanating from deeper within the stone.

	In quartz, needle-like rutile inclusions also are responsible for both of these stars.

	The researchers repolished some of the synthetics and found that when the dome was repolished, the white star disappeared; when the base was repolished, the body colored star disappeared. This indicated that the material was diffusion treated because the needle inclusions were confined to the surface.

Digital Photomicrography for Gemologists

	Photomicrography – photographing tiny gemstone inclusions with the use of a microscope – serves both research and artistic purposes.

	Until recently, the practitioners of this art used film instead of digital methods because of the superior color rendition and resolution that film once offered. But digital photomicrography has advanced to the point where it is in many ways superior to film, with the added benefit that the photographer can instantly see the results and easily make adjustments to the image.

The black manganese oxide “plumes” in this Australian opal serve as a good example of art and science merging in gemology. Photomicrograph by Nathan Renfro, field of view 5.85 mm. Note: Field of view is horizontal throughout this paper unless otherwise specified.

This article by GIA researcher Nathan Renfro details basic aspects of photomicrography, including selecting the proper gemological microscope and digital camera. It is important to make sure the camera has remote control capabilities, vibration control and the ability to take very high-resolution images.

	The author leads the reader through the steps of mounting the camera to the microscope, cleaning the gemstone and setting up the proper lighting. Darkfield illumination, generally the norm for gemological examination, is not always best for photomicrography because of the strong contrast between inclusions and background. Dust particles and scratches become very conspicuous. As a result, photographers should be able to employ a variety of lighting techniques, such as brightfield, diffused, fiber-optic, polarized, ultraviolet and the lesser-known differential interference contrast system (sometimes in combination).

	As in any photographic pursuit, capturing the image is only the first step. Processing to render the image as close as the actual subject as possible, beyond standard Photoshop, is the second step. This requires processing software that can improve focus – extending depth-of-field is a must because of the high magnification and extremely tight focal lengths. High dynamic range (HDR) software is also critical to combat overly bright or dark areas and to enhance detail. Some cameras, including phones, have HDR capability built in. Finally, it helps to include a scale bar that indicates the magnification in use and the size of the view field to give context to the final image.

Rubies and Sapphires from Snezhnoe, Tajikistan

	Ruby is one of the world’s most-desired gemstones. In this article a team of mineralogists and educators from Russia, Germany and Tajikistan report on a little-known deposit in Snezhnoe, Tajikistan, located very close to that country’s border with western China.

Left: Brown prismatic rutile inclusions within ruby from Snezhnoe. Photomicrograph by Elena S. Sorokina, magnified 35×. Right: A backscattered electron image of zircon (Zr) and rutile (Rt) inclusions in pink sapphire from the deposit (Cal = calcite, Mrg = margarite). From Sorokina (2011).

	This deposit was discovered in 1980, when the country was still part the Soviet Union. Soviet authorities estimated reserves of “hundreds of thousands of carats of gem corundum,” but kept actual production figures secret while mining between then and 1990. Mining resumed in the past decade, though the state-run enterprise still does not disclose production amounts.

	The Snezhnoe ruby deposit lies about 20 to 25 feet below the surface between layers of marble. The authors analyzed several dozen ruby-bearing rocks mined earlier and found the gems’ color ranged from pink sapphire, purple-red to bright red, with chromium levels similar to the well-known Mogok rubies. The researchers (Elena Sorokina and coauthors) found that Snezhnoe material has distinctive inclusions not found in ruby from any other locale: allanite, fuchsite and muscovite. These features can be used to help gemologists identify the source of these stones.

Micro-World

	The debut of the Micro-World section includes a look at a 30-million-year-old polished Dominican amber containing a long-legged mite, as well as a dark green apatite that, when broken, yielded a fascinating orange calcite inclusion. Upon magnification, the spherical inclusion had the appearance of a round orange mask with purple fluorite “eyes.” The Micro-World team (Nathan Renfro, Elise Skalwold and John Koivula) also examined a bi-color double-eye cabochon tourmaline that showed a pink band on one side and a colorless band on the other, despite the fact that the chatoyancy-causing growth tubes − shown clearly in the photomicrograph − were only in the colorless portion.

Lab-Notes

Diamonds

	The GIA lab in Bangkok examined six melee-sized colorless HPHT synthetic diamonds, ranging in size from .005 ct. to .01 ct. These synthetics, which were disclosed samples sent for research, showed no tell-tale inclusions or distinct absorption lines. The DiamondView device revealed blue or green fluorescence and characteristic growth patterns of synthetics.

Three LPHT-annealed CVD synthetic diamonds: Fancy Deep brownish orangy pink 0.37 ct (top left), Fancy Deep brown-pink 0.31 ct (top middle), and Fancy brown-pink 0.25 ct (top right). Their DiamondView images (bottom row) show orange fluorescence with linear growth striations.

	In addition, the New York lab examined three pink-to-brown CVD-grown diamonds that were further treated by a process known as low-pressure, high-temperature (LPHT). The diamonds, which weighed 0.37, 0.31 and 0.25 ct., were heated and subjected to low pressure to enhance their color. DiamondView imaging showed these diamonds had the orange fluorescence and linear growth striations typical of CVD synthetics.

This 1.18 ct Fancy Intense blue diamond was recently seen in the New York lab.

	The New York lab examined a 1.18 ct. natural type IIb Fancy Intense blue diamond that showed an extremely high concentration of boron – 5.84 parts per million. Most blue diamonds, like the type IIb Hope Diamond, have boron concentrations between 0.24 ppm and 0.36 ppm. This was the highest boron concentration GIA researchers have ever seen in a natural diamond.

	Another extraordinary type IIb was a natural 1.42 ct. Fancy gray-purple diamond submitted to the Carlsbad lab. The diamond was unusual for its color, but also for its extremely strong photoluminescence.

Pearls

	GIA researchers examined several unusual cultured pearls, one a large cream and white colored baroque shaped piece with an unusual translucent ring on one side. Upon examination, the pearl was found to be assembled, with a new section of nacre applied to an area that had broken off. The second was a necklace of Chinese cultured pearls with a strong pinkish-purple color. Tests showed these to be cultivated in fresh water, demonstrating that Chinese producers are growing ever larger and higher-quality pearls.

Sapphire

	Beryllium diffusion and lead-glass filling treatments have been well-publicized in the past decade. The GIA lab in Carlsbad recently examined a 4.25 ct. orange sapphire that had undergone both treatments. Magnification revealed numerous fractures filled with glass. Further testing revealed that it was treated with beryllium (Be). Because the Be treatment requires much higher temperatures (1800 to 1850 degrees C) than the glass filling process (900 to 1400 C), it was certainly done first. It was the first time GIA had encountered a gemstone with both treatments. @topic:3


Publish Year: 2015 Title: The Beauty and Value of Inclusions, Plus Double Stars and Corundum from Tajikistan Abstract: We hope you enjoy this edition’s unusual and distinctive cover image. It’s especially fitting, as a number of contributions in this issue deal with aspects of gem inclusions: their documentation using modern digital photography and image-processing software, how some interact with light inside a fashioned gem to produce asterism, and the straightforward instructional value that might be gained through their study.

Our cover article, by Nathan Renfro, analytical manager of the gem identification department at GIA’s Carlsbad laboratory, focuses on digital photomicrography for gemologists. Renfro’s article builds on the landmark 2003 paper by his longtime mentor and master of gem-inclusion photography John Koivula, to offer a highly practical and relevant guide covering equipment and current techniques for the gemologist.

In the lead article, we present a paper by a team of researchers headed by Dr. Karl Schmetzer, a frequent contributor to Gems & Gemology during the 1980s and 1990s. We are delighted to welcome Dr. Schmetzer back to our journal. He and his coauthors offer a comprehensive description of a largely unappreciated form of asterism: the dual-color “double stars” observed in some natural sapphire, ruby, and quartz, as well as synthetic corundum, including diffusion-treated examples. The authors discuss the mechanism by which double stars are formed and present a historical summary of the manufacture and improvement of synthetic star corundum by diffusion treatment.

		We invite gemologists to take a closer look at the astounding beauty and variety of the micro-world of gems.

Our third article, by Russian researcher Dr. Elena Sorokina and her coauthors, provides an update on the geology, mining, and internal and external features of ruby and sapphire from Snezhnoe, Tajikistan. This is a welcome summary of a marble-hosted deposit with significant potential, one that has seen little study or previous coverage in the gemological literature.

After these three feature articles, you’ll find our regular Lab Notes and Gem News International sections, which include further entries from the 2015 Tucson shows and a report of the recent Maine pegmatite workshop.

In addition, we present a new quarterly column on inclusions entitled “Micro-World.” With this new regular feature, section editors Nathan Renfro, Elise Skalwold, and John Koivula aim to foster the wider appreciation of inclusions and to bolster practicing gemologists’ observational skills by providing concise reports accompanied by stunning photomicrographs of specially chosen specimens. The authors invite gemologists to take a closer look at the astounding beauty and variety of inclusions in gems.

Finally, I'd like to thank Stuart and the entire G&G editorial and production staff. Due to the unexpected death of a close family member, I have been out of the United States for a period of weeks. As a result, I have come to appreciate the hard work and dedication of the entire G&G team even more.

All of us at G&G hope you enjoy the Summer issue! @topic:3


Publish Year: - Title: Update on Rock Creek Sapphire Deposit Abstract: Figure 1. Excavators and a washing plant on Gem Mountain process gravel for sapphire recovery. Photo by Warren Boyd.

                      Recently, Montana-based Potentate Mining LLC secured approximately 3,000 acres of sapphire-bearing ground covering the famous Rock Creek sapphire district, including the Gem Mountain sapphire mine, near Philipsburg, Montana. Since the discovery of these sapphire deposits in the 1890s, this is the first time that one company has consolidated such a large land position, encompassing the old alluvial sites as well as the area on the hills in between these old workings (figure 1). Potentate has assembled a team of highly experienced placer miners, geologists, mining engineers, and heavy equipment operators to recover and process the sapphires from this mine.

The Rock Creek district sapphire deposits occur in debris flow, colluvium, and secondary alluvial deposits (figure 2). Although the bedrock for these deposits has not yet been defined, Potentate plans further geological mapping and geophysical surveys in the near future to uncover these sources.

Figure 2. A trench on Gem Mountain showing the sapphire-rich colluvium on the hilltops between the previously worked gulches. Photo by Keith Barron.
To date, the rough sapphires recovered from the bulk sampling pits range in size from 0.25 ct to over 20 ct. Approximately 15% of this rough occurs naturally in marketable colors, including pink, orange, orange-pink, lavender, golden yellow, blue-green and green, and fine blue (figure 3). A substantial percentage of the remaining rough responds very well to heat treatment technologies that improve clarity and turn greenish and grayish rough to desirable colors such as blue, orange, yellow, pink, and parti-color.

	Figure 3. A selected assortment of unheated rough sapphires from the Rock Creek deposit
	weighing from 0.50 to 17 ct. Photo by Warren Boyd.
The high-grade concentration of the sapphires recovered from the various test pits, and the substantial inferred rough sapphire resource on Gem Mountain, indicate that Potentate would be able to provide a long-term, consistent supply of sapphire rough to the global market (figure 4). Potentate would be the only large-volume source for the Rock Creek sapphires. The company is developing a marketing strategy that would provide sustainable supply chain guarantees to their clients. These clients including wholesale gemstone cutters, polishers, and fine jewelry retailers would in turn be able to provide guarantees of origin and the presence (or absence) of any heat treatment to their consumers.

	Figure 4. A selection of natural and heat-treated Rock Creek sapphire ranging from 0.50
	to 4.70 ct. Photo by Jeff Scovil. @topic:2


Publish Year: 1981 Title: Emeralds of Colombia Abstract: There has been more activity in emerald mining in Colombia in the last few years than at any other time in the four centuries since the Spanish first discovered the deposits. This article combines a comprehensive review of the literature on the history and geology of Colombian emeralds with the author's own insights into the current marketing and mining of these stones. Of particular concern are the harsh methods now being used to extract the emeralds and the impact these methods will have on future production in Colombia. The past, however, has yielded many fabulous gems, the most famous of which are also described here and placed in historical perspective. @topic:9


Publish Year: - Title: An Inside Look at the 2014 Tucson Shows Abstract: Buyers of every stripe walk the aisles for choice finds at the 2014 gem show in Tucson. Photo by Eric Welch.

                      Every year in February, Tucson, Arizona, becomes the center of the colored stone industry, hosting several major gem and mineral shows. Dealers, cutters, and miners come from all over the globe, bringing with them a spectacular array of gems to sell. In 2014, GIA once again interviewed industry professionals at the shows to see the very latest and gather insight on the global market. Links to these interviews are listed below.

Exceptional Gem Artistry in Sunstone, Rutilated Quartz, and Beryl – Tucson 2014
Gem cutter Alexander Kreis of Idar-Oberstein relates his approach to unlocking the beauty of rough gemstones such as Oregon sunstone, beryl, and rutilated quartz. He describes the influences that play into his unique designs, whether it’s the pure, crystalline beauty of a flawless piece of rough or the presence of striking inclusions.
Learn More

Natural-Color Tanzanite and Yellow Sapphire – Tucson 2014
Israeli dealer Kobe Sevdermish introduces us to the subtle beauty of unheated tanzanite, bright yellow African sapphire sought after by his clientele as a fancy-color diamond substitute, and the rich, earthy colors of heated zircon from Tanzania.
Learn More

Gem Crystals – Tucson 2014
Industry veteran Steve Ulatowski notes how recent market changes have driven prices for rough colored stones of all types to unprecedented heights. He explains the impact on his business and reveals some of the key factors behind these shifting market dynamics.
Learn More

Innovative Optical Effects, Unique Rings with Raw Crystals – Tucson 2014
Husband-and-wife team Brian and Kendra Cook reveal the design philosophy behind their unique gemstone products, which use “raw” gem crystals, clever optical effects, or aromatic oils to tantalize the senses in a combination of texture, color, and scent.
Learn More

Mexican Fire Opal – Tucson 2014
Tucson is a showcase for fascinating and diverse gem materials. Included in this segment are emerald, quartz, and liddicoatite tourmaline crystals, Taiwanese “seven-color jade,” synthetic quartz from Russia, treated Brazilian quartz, and turquoise and benitoite from the United States.
Learn More

More of the Interesting and Unusual – Tucson 2014
The Tucson Gem Show provides a venue for a myriad of fascinating and diverse materials. Included in this segment are fascinating emerald, quartz, and liddicoatite tourmaline crystals, decorative objects made from Taiwanese ‘7-color jade,’ synthetic quartz from Russia, advice for choosing star rose quartz rough, treated Brazilian quartz, and finally turquoise and benitoite from the United States.
Learn More

Red Beryl – Tucson 2014
Ray Zajicek of Equatorian Imports Inc. displays some exceptional examples of red beryl from Utah, in both loose form and in suites of jewelry. As mining there has ceased, this material is likely to become an increasingly scarce commodity.
Learn More

Varieties of Rutilated Quartz – Tucson 2014
Bill Heher of Connecticut-based Rare Earth Mining Co. shows exceptional rutilated quartz from Bahia in northern Brazil. Thanks to its seemingly infinite variety and one-of-a-kind appeal, this material is popular among contemporary jewelry designers.
Learn More

Fossilized Drusy Shells – Tucson 2014
Tarun Adlakha of Indus Valley Commerce in New Delhi exhibits fascinating fossilized gastropod shells replaced by chalcedony and encrusted with drusy quartz.
Learn More

Cultured Pearl Market Update – Tucson 2014
Fran Mastoloni of Mastoloni Pearls in New York offers a cultured pearl market update. He discusses current design trends in pearl necklaces and urges retailers to embrace the rich variety of cultured pearl types available today.
Learn More

Fine Australian Chrysoprase Rough and Carvings –Tucson 2014
Mary Lou Osmond of Candala Chrysoprase talks about the company’s chrysoprase chalcedony mine in Marlborough, Australia. She explains that growing demand has customers purchasing her top-quality material to produce calibrated cabochons in addition to the carvings that were once the mainstay.
Learn More

Fine Corundum, Paraíba Tourmaline, and Alexandrite – Tucson 2014
Dave Bindra of B&B Fine Gems in Los Angeles comments on the corundum, Paraíba tourmaline, and alexandrite markets. He displays exceptional specimens from his booth at the AGTA show, including a 112.82 ct alexandrite, a 33.16 ct blue sapphire, and an electric blue 14.59 ct Paraíba tourmaline.
Learn More

Stone and Fossil Photography – Tucson 2014
Mike Woodward of San Clemente, California, showcases striking photos of stones, fossils, and gem materials that resemble abstract paintings or landscapes.
Learn More @topic:11


Publish Year: 1986 Title: Pink Topaz from Pakistan Abstract: In addition to the relatively recent discovery of significant amounts of emerald, aquamarine, and ruby, Pakistan has also begun to produce fine gem-quality pink topaz. In a small hillock of recrystallized limestone north of Katlang, narrow calcite veins encase pink topaz crystals up to 3 cm long accompanied by larger amounts of reddish brown, tan, and colorless topaz crystals. More than 70,000 ct of gem-quality pink topaz has been reported to date. The refractive indices, optic axial angle, unit-cell dimensions, and density of the topaz are influenced by a partial replacement of fluorine by hydroxyl ions. The color is due to trace elements—principally chromium (Cr3+). Treatment experiments revealed that the color of the brown, tan, and colorless topaz from this source may be improved by irradiation and heat. @topic:1


Publish Year: - Title: Extraordinary Gemstone Sculptures Make Debut at GIA Abstract: View Gallery

The display of Perry Brent Davis’s carvings of agate and gem quartz at GIA’s Carlsbad campus looks like a colorful seascape of otherworldly designs. Many float above sensuously curved bronze arms; others are grounded on sleek blocks of black granite. Each is carved and highly polished to showcase its internal features and patterns.

	“I choose stones that exemplify the power of nature,” Davis says. He finds “some of the most beautiful, naturally colored minerals the earth produces” and turns them into works of art.

	“This incredible medium forms my raw material – often there are natural crystal pockets and features that accentuate the simple form of my contemporary pieces,” Davis says. Several of the designs, for instance, reveal drusy-lined interior pockets that sparkle against the high polish of the exterior surface.

	Davis, a graduate gemologist with three decades of experience in the gem and lapidary fields, moved to China from the U.S. in 2006 to pursue his interest in large gemstone carvings. He opened a studio and hired a team of traditional carvers. He and his team incorporate modern and ancient Chinese carving techniques into each piece.

	The results are larger-than-normal gemstone sculptures that emphasize the rich colors, ornamental patterns and internal features in agate, rock crystal and jasper. Most of the design process takes place on the stone itself, Perry says, and is refined as the carving evolves. It can take 200 to 1,400 hours to complete a piece, but many fall in the 200-500 hour range.

	“To get such amazing carvings in such large sizes is a feat,” says Terri Ottaway, curator of collections for the GIA Museum. “But then to carve and polish them so beautifully to bring out the intricate patterns is quite an accomplishment and rarely seen.”

	Davis gets his rough pieces from mines in the U.S., Mexico, Brazil and Austrailia. He says that going to the mines is "like going to Las Vegas" unless he knows an owner is going to be there with rough. He says he has better luck at gem and mineral shows where there are large quantities at good prices.

	Davis selects gemstones that are technically complex and require a vast array of diamond tools and other equipment to carve. Working on them requires a high level of technical ability and articulate workmanship, according to Nathan Renfro, a gemologist in GIA’s Carlsbad laboratory who is also a gem carver.

	“From the captivating design to the quality of his workmanship,” Renfro says, “each piece Davis creates makes it clear he is a world-class artist and gem carver.” @topic:6


Publish Year: 2012 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. @topic:2


Publish Year: - Title: From the Andes to the Pantanál: In Search of Ametrine Abstract: Before preforming, ametrine is often examined under a bright light to reveal the best purple/yellow orientation of the rough for subsequent cutting.

Introduction
The highest peaks of the Andes Mountains tower majestically over Bolivia. At over a million square kilometers, an area twice the size of Texas, this country occupies a fairly large share of central South America. The Andean mountain chain, known as the Cordilleras, lie in the eastern third of the country, and the majority of Bolivia’s ten million people live here, as they have since pre-Columbian times. Even after the Spanish conquistadores laid claim to this rich and beautiful land in the early 1500s, the Andes remained the country’s lifeblood.

	Most of Bolivia’s ten million people live in the Andes Mountains. The Huayna Potosi mountain is located just north of La Paz.
We bring you to the source of one of the world’s most unique gems: ametrine. In this gem, nature has combined two quartz varieties, purple amethyst and golden citrine. Ametrine is found only in this exotic Andean nation, a land as unique as the gem it produces.

	This 44.00 ct ametrine features concave facets that combine to mix the color of the purple and gold, producing a beautiful effect. Courtesy of Minerales y Metales del Oriente.
The goal is to better understand ametrine and its origin, as well as the people who mine it and treasure it.  We’ll take you to the Anahí mine itself, getting our hands dirty as we clamber through the very tunnels and shafts that pierce the earth’s crust to produce this unique gem material. There you will see how the ametrine gets transported and processed, and then the final act of making the gem ready for jewelry. Finally, we’ll take you to a glamorous showroom in Bolivia that specializes in selling these treasures. In all, you will have a true mine-to-market experience.

But our journey through Bolivia begins high in the Andes—far from the tropical environment that produces ametrine.

	Huayna Potosi mountain and Lake Titicaca.
Bolivia’s Highlands
Bolivia’s highest peak, El Nevado de Sajama, rises 21,400 feet above sea level and remains cloaked in a permanent snow bank, as do many of the other impressive peaks in the Andean Cordilleras. It is the snows from the Western and Central Cordilleras that nourish Bolivia. The melt-off rushes down the mountains toward the Altiplano, a high plain that is home to the world’s highest navigable body of water, Lake Titicaca. It is also the largest freshwater lake in South America, and visible from outer space, and home to fascinating, high-altitude flora and fauna such as the James flamingo, once thought to be extinct before it was rediscovered in the mid-1900s.

The roots of Bolivia’s history—and the bulk of its population and cultural and mineral riches—lie in these high, austere elevations of the Altiplano. In this arid, seemingly inhospitable location, the mighty Tiwanaku civilization once thrived. Tiwanaku is thought by historians to be a precursor to the mighty Inca empire, and its people inhabited the region around Lake Titicaca as early as 1500 BC. Evidence suggests a civilization dedicated to agriculture. At the height of the civilization, around 300 BC, this region was likely the source of many of the world’s potato varieties, as well as unique forms of barley and quinoa and domesticated camelid species such as the llama, vicuña and alpaca. The people were also exceptional stonemasons. A visit to Tiwanaku, Bolivia’s most important archaeological discovery and a UNESCO World Heritage Site, exemplifies their extraordinary architecture and stone carving for decorative or ceremonial purposes. One of the most important icons there is the Puerta del Sol (Gate of the Sun), a giant monolith carved with a stunning design of the sun god Inti wearing an elaborate headdress and surrounded by humanlike birds.

	At Tiwanaku, Bolivia’s most important archaeological site, lies Puerta del Sol ("gate of the sun"). This ancient pre-Colombian rock monolith depicts the sun-god "Inti" which is  Bolivia's principal icon.
While Bolivia’s rivers and high-altitude lakes are nourished by the Andes, so are its people. In fact, the bulk of Bolivia’s population is concentrated in the Andean region. In the 1500s, the Spanish began to inhabit and colonize these areas, often returning to Europe with raw materials found in the New World. From mineral-rich Bolivia (known at the time as the Great Colombia), silver, gold and other treasures were taken in huge quantities. These contributed greatly to the growth of the Spanish Empire in the 1500s and 1600s.

	A Bolivian llama herder in the Antiplano region.
Potosí
If we see ametrine as a colorful reminder of Bolivia’s gem and mineral riches, it was precious metals, particularly gold and silver, that were most sought in the 1500s and 1600s. The city of Potosí epitomizes the treasures that pour out of the Andean region. An interesting story relates the discovery of silver in the year 1544. Huallpa, an Incan llama herder, had lost one of his animals, and rather than return home without it he spent the night on the mountainside. With the perpetual cold at this altitude, even more so once the sun sets, Huallpa built a fire to stay warm. As the legend goes, tiny threads of molten silver began to flow in small rivulets from under the coals, a mother lode of silver.

	The city of Potosi produces much of the world’s silver. Cerro Rico lies in the background.
For nearly 500 years since this discovery, Cerro Rico has been the world’s largest silver deposit. It is also one of the highest working mines in the world, located a punishing 14,000 feet above sea level. Of this discovery it was once remarked that a bridge of solid silver could be built, stretching from Potosi to Spain. This was figuratively true, as much of Cerro Rico’s wealth went directly to Spain in the following centuries. In attempting to create a Bolivian silver industry in the 1500s, the Spanish viceroy built the national Bolivian mint, La Casa de la Moneda. This truly imposing structure struck most of South America’s silver currency, as well as some of Spain’s own currency, for well over two centuries.

	Courtyard of La Casa de la Moneda, Bolivia’s national mint since the 1500s.
A rare view from the roof of La Casa de la Moneda today portrays a city whose architecture has remained virtually unchanged for the past 500 years. A series of colonial churches, brick and stucco buildings with red tile roofs, huddle together as if seeking warmth against the cold, barren landscape.

Overlooking Potosí is the now heavily pockmarked mountain of Cerro Rico, often depicted in Bolivian paintings as a sacred figure protecting the city and its people.

The Legend of Anahí
Bolivia’s colonial era is a good time to introduce the legend of Anahí, which touches upon the gem ametrine. The Spanish conquistadores were likely sending teams of explorers throughout the Andes starting in the 1500s, and their journeys led them down the high valleys into the lowlands and eventually the Amazon basin. Their charge was to discover as much gold and silver as possible for the homeland. One such explorer is said to have encountered a native Ayoreo tribe along the Pantanál region and, in a Pocahontas-like story, fallen in love with Anahí, an Ayoreo princess. As a token of her admiration for the conquistador, she presented him with a bicolored gem, one the Spaniards had never seen before. The rare stone was found near the village, in a mine that bears her name today.

As laced with romance as the story might be, the ametrine as know it today likely came much later, in the 1970s.

Sucre and La Paz
Bolivia’s constitutional capital is Sucre, located in the high mountain valleys. And while the city is one of the country’s largest, bustling with activity, it is no longer the seat of government. All the major government offices, the president’s home, and the international embassies are now located in La Paz. Nonetheless, Sucre is a magnificent colonial city to visit because of the wonderful mix of modern conveniences and ancient history blended together there. Sucre is centrally located, linked by railroad to Bolivia’s principal silver and tin mines, and from there to other main cities and export centers.

	In the Andean village of Tarabuco, many still wear leather replicas of old conquistador helmets.
Not far from Sucre is the village of Tarabuco, today a quaint community known for the amazing color and quality of its textile designs. But Tarabuco’s reputation was not always so peaceful. The Tarabuqueños were fierce warriors, ancestrally linked to the Incas and vigorously opposed to Spanish rule. A visit to the small town reveals a society lost in time, and one still gets an uneasy sense that outsiders are unwanted. The main square has as its centerpiece a ferocious Tarabuqueño statue, a wild-eyed man who has just ripped the heart out of a Spanish soldier’s chest. Despite their opposition to the Spaniards, the conquistadores clearly left their mark. Remarkably, vestiges of ancient Spanish influence are still seen centuries later. To this day, men and women often wear leather replicas of the old conquistador helmets, sometimes adorned with flowers.

La Paz, meanwhile, is truly international, the highest major city in the world. Here too the Bolivian partiality for hats is seen everywhere you go. In the La Paz region, the hats take on a more European flair. Women enjoy wearing black and brown felt hats, similar in style to an English “bowler” hat. The city a Bolivian woman comes from can often be determined from the type of hat she wears.

Overlooking La Paz is one of Bolivia's most dramatic mountains, Mount Illimani, which is permanently blanketed in snow and towers over the capital. Nestled in a deep bowl on the Altiplano, La Paz lies within easy reach of Lake Titicaca and Bolivia’s other main cities. A short but hair-raising drive to the cumbre, the highest mountain pass, some 20 miles outside the city, provides a bird’s-eye view of the city’s skyscrapers. Peering down the other side of the mountain, however, brings into view a precipitous plunge into the beginnings of Bolivia’s jungle lowlands. We will now proceed past the high valleys, following the melting snows and rivers into the jungle below, in search of ametrine.

Getting There
A half-hour flight from La Paz deposits visitors in the fast-growing city of Santa Cruz, in Bolivia’s tropical heartland. We are one step closer to the birthplace of ametrine. Our first stop in Santa Cruz is a visit with Ramiro Rivero, owner of Minerales y Metales del Oriente. This parent company encompasses a group of companies dedicated to mining, transporting, sorting, preforming, faceting and marketing all of Anahí’s gems. While ametrine is the most coveted gemstone, the mine also produces a variety of other quartzes, including amethyst, citrine, and colorless and lavender quartz.

The best way to get to Anahí is by invitation. Given the utter remoteness of the locality, those arriving unannounced are not welcomed with open arms. Assuming that an invitation stands, the travel choices are limited. In practical terms, there are really only two ways to get there: the drive and boat ride, or the flight from Santa Cruz. One could take the route of the conquistador and traverse miles of scrub brush and deep jungle by horse—which is not recommended. Another option would be to wait until the dry season (Bolivia’s winter months, such as June or July) and take the daylong drive along a rural road from Santa Cruz. The road meanders southeast to the village of Roboré, and from there to the town of Puerto Suarez, on the border with Brazil. This completes the land portion of the journey, approximately two-thirds of the way to the mine. An extraordinary network of swamplands and inland waterways, which make up the world-famous Pantanál ecological reserve, are the next leg of the trip. Another 8 to 10 hours are spent on a barge or motorboat, heading due north until reaching Laguna Mandioré, a large freshwater lagoon. Along its shores, a small port serves as a disembarkation point… and then for the last bumpy hour of the trip, a winding slog through the jungle, over a small series of hills to Anahí.

	This aerial photo shows the area near the Anahí mine in southeastern Bolivia. The mine is near the center of the shot, barely visible amid the foliage between the two mountains.
The most expeditious way to the mine is by single-propeller aircraft, a three-and-a-half hour flight from Santa Cruz. Not far from the mine, a grass airstrip awaits, and heavily armed guards are there to greet you.

	A single-propeller aircraft lands on the airstrip at Santa Cruz, near the Anahí mine.
Anahí
Upon reaching the mine, it becomes immediately clear that the place is all about quartz. Chunks of different sizes, including outright hexagonal crystals, are embedded along the road leading to the mine and throughout the mine itself. The hills surrounding the mine property consist of dolomitic limestone, containing veins of quartz. Several different shafts have been drilled into the property along these veins, and Rivero estimates that in a good year 3,000–3,500 kg of gem-quality quartz are mined. Ametrine is the most lucrative of the products, though on average amethyst makes up 44% of production by weight, ametrine 33%, and citrine 23%. A portion of the production is very light, lavender-colored, which Rivero has called “anahíta.” Some colorless or very milky quartz, previously discarded, is now retained for ornamental purposes.

	Fernando Arrien of Minerales y Metales del Oriente examines some large amethyst specimens at the Anahí mine.
In a good year, some 70 to 100 individuals work at the mine. Rivero takes great pride in describing how the mine is run. He says the miners play soccer every day, eat good food, watch satellite television, and use the company’s phones to call home. Alcohol is prohibited at the mine, and the company provides basic medical care.

	This 80.30 ct ametrine fantasy cut is courtesy of Minerales y Metales del Oriente.
The Mining Process
Most of the mining at Anahí takes place underground, accessed through a series of reinforced shafts and horizontal tunnels that extend to the mineralized areas. But there is also a small open-pit mining area. In the tunnels that are being enlarged, or when mineralized areas in the open pit need to be loosened for hand digging, dynamite blasting occurs once or twice per day. An alarm is sounded, and everybody seeks cover.

The air must be cleared after blasting, and then the miners remove loosened rock or chisel into areas containing amethyst. In the principal tunnels, overburden is piled into mining carts that roll down a slight grade when full. A single person pushes the carts. The overburden is transported up an elevator shaft and slid down a chute to another waiting mining cart in open air. Fully loaded carts are pushed to a washing area where the material is dumped. A water cannon further loosens agglomerations of rock and mud, and a series of sieves are used to separate out particulate matter. The Anahí mine is conscious of environmental damage from particulates, particularly if these were to flow downstream into the Pantanál. Particulates are therefore meticulously collected in a series of holding ponds.

	Mining operations at the Anahí mine.
After washing, material is bagged and taken to a protected presorting facility. Here some 20 employees begin evaluating the material. Some items are hammered—or cobbed—to reveal only facetable material, and to reduce weight. While no items are actually faceted at Anahí, the presorting is aimed at streamlining the cutting process later.

The mine prides itself on compliance with government regulations on the use of dynamite. Miners also wear protective gear such as hardhats, gloves (quartz can cut as easily as broken glass), eye protection, and masks to protect the wearer from airborne quartz particles.

The return trip is also arduous. Mine run is trucked to Laguna Mandioré and loaded onto a barge. From there it makes the long journey down to Puerto Suarez, where it is transported to a holding facility. Rough material is then shipped to the processing plant in Santa Cruz— as needed.

	This worker is prewashing the rough that comes out of the mine. Sediments of varying weight are collected in holding ponds to prevent water contamination downstream of the mine.
The Manufacturing Process
The main facility for processing the mine run and transforming the material into sparkling gems is located at the Parque Industrial in Santa Cruz. Here the material is categorized and sorted further, dutifully routed to the proper preformers and cutters at the factory. Preforming reveals the ametrine’s color zoning, which allows a skilled cutter to determine the final outcome of the gem. He or she must also work to fashion the gems to perfectly fit the factory’s jewelry design, or according to the specifications of overseas manufacturers. Because the designers, preformers, cutters, and jewelers are all located under one roof, clear communication is needed. An informal open-door policy encourages this type of communication.

	This woman at the Anahí mine is combing and sorting the quartz prior to sending it to Santa Cruz for faceting or preparation for export.

	At Minerales y Metales del Oriente, the parent company of the mining group, cutters work in an organized environment and wear masks to avoid inhaling the silica dust created as they cut and polish stones.

	This young woman at Minerales y Metales del Oriente is sorting amethyst, ametrine, and citrine.

	At the Minerales y Metales del Oriente processing plant, ametrine is cut and polished and prepared for jewelry. These models produced by CAD/CAM are for mounting ametrine in jewelry.
End of the Line
Now the finished jewelry is finally ready for its ultimate destination, the market. While a portion of the rough and preformed amethyst, ametrine, and citrine production is slated for export to markets around the world, M&M’s own retail division stands as a profitable test market for selling finished products in a retail environment. M&M’s spotless showrooms in Santa Cruz serves as a forum for aspiring, as well as accomplished writers, artists and musicians, who are often invited to exhibit their work or perform at the store. In turn these guests respectively carry the message of Anahí throughout the country. This strategy has not gone unnoticed. Ametrine, also known as “Bolivianita,” is the country’s national gemstone.

	Minerales y Metales del Oriente’s retail division sells finished ametrine jewelry sourced from the company’s Anahí mine. This photo was taken inside an M&M showroom boutique.
Ametrine serves as a spectacular mine-to-market model for anyone seeking to elevate the status, market appeal, and value of a given gemstone. And in examining the source of this unique gemstone, we have gone further—to understand the culture, beauty, and historical background of Bolivia.

	 This 17.80 ct ametrine is a stylized briolette. Courtesy of Minerales y Metales del Oriente.

	This 48.90 ct ametrine with concave faceting was cut by Dalan Hargrave. Courtesy of Minerales y Metales del Oriente. @topic:1