Publication Year: 2018 Title: Nominal Type IaB Diamond with Detectable Uncompensated Boron Abstract: Figure 1. This 0.30 ct K-L diamond with faint brown color, mounted in an 18K gold prong setting, is a nominal type IaB diamond with detectable uncompensated boron. Photo by Wenqing Huang.

In recent years, nominal type IaAB and IIa diamonds with transient 2800 cm–1 FTIR absorption peaks arising from uncompensated boron produced under UV radiation have been reported (J. Li et al., “A diamond with a transient 2804 cm–1 absorption peak,” Journal of Gemmology, Vol. 35, 2016, pp. 248–252; Winter 2016 Lab Notes, pp. 412–413). The National Center of Supervision and Inspection on Quality of Gold and Silver Products recently examined a type IaB diamond that exhibited instantaneous 2803 cm–1 FTIR absorption shortly after exposure to an ultra-short-wave (< 230 nm) UV source.

Figure 2. DiamondView imaging shows blue fluorescence (left) and greenish blue phosphorescence (right) in the natural type IaB diamond. Images by Wenqing Huang.

Figure 3. The FTIR spectra reveal low concentrations of the hydrogen peak (3107 cm–1) and nitrogen impurities in the B aggregates (1174 cm–1) (blue line). Shortly after ultra-short-wave (< 230 nm) UV exposure, the transient boron-related absorption was recorded at 2803 cm–1 (red line). Spectra have been offset vertically for clarity.
Under ultra-short-wave UV excitation, the 0.30 ct K-L diamond with faint brown color, mounted in an 18K gold prong setting (figure 1), showed strong blue fluorescence and strong greenish blue phosphorescence that lasted for approximately eight seconds (figure 2). Infrared absorption spectroscopy showed low concentrations of the hydrogen-related peak (3107 cm–1) and nitrogen impurities in the B aggregates at 1174 cm–1 (figure 3), indicating a type IaB diamond (C.M. Breeding and J.E. Shigley, “The ‘type’ classification system of diamonds and its importance in gemology,” Summer 2009 G&G, pp. 96–111); prior to ultra-short-wave UV excitation, we were unable to detect the presence of the B center. No boron-related absorption was detected before UV radiation exposure, due to uncompensated B concentrations below the detection level of the FTIR spectrometer. But shortly after ultra-short-wave UV exposure, the transient boron-related absorption peak was recorded at 2803 cm–1 (again, see figure 3). Nitrogen-related peaks were detected at 415.7, 428.5, 439.0, and 452.4 nm using photoluminescence (PL) spectroscopy (figure 4); the peak at 415.7 nm belongs to the zero-phonon line (ZPL), while the others belong to its associated phonon replicas (A.M. Zaitsev, Optical Properties of Diamond: A Data Handbook, Springer-Verlag, Berlin, 2000). PL and FTIR spectra confirmed the diamond’s natural origin.

Figure 4. The photoluminescence spectrum of the sample excited at room temperature with a 405 nm laser reveals an N3 center with its zero-phonon line (ZPL) at 415.7 nm and its associated phonon replicas with peaks at 428.5, 439.0, and 452.4 nm.
The generally accepted mechanism for interpreting the phosphorescence in type IIb diamonds is donor-acceptor pair recombination processes involving boron and other defects (P.J. Dean, “Bound excitons and donor-acceptor pairs in natural and synthetic diamond,” Physical Review, Vol. 139, 1965, pp. A588–A602). Boron is deemed as the acceptor in the model, where the donor is believed to be nitrogen related, either as isolated nitrogen, aggregated nitrogen, or a plastic deformation–related defect (S. Eaton-Magaña and R. Lu, “Phosphorescence of type IIb diamonds,” Diamond and Related Materials, Vol. 20, 2011, pp. 983–989; E. Gaillou et al., “Boron in natural type IIb blue diamonds: Chemical and spectroscopic measurements,” American Mineralogist, Vol. 97, 2012, pp. 1–18). When almost all of the boron impurities received electrons from donors, almost no uncompensated boron (B0) was left behind, and therefore no boron-related absorption peaks were recorded. When the diamond was exposed to ultra-short-wave UV excitation, some of the compensated boron converted to an uncompensated state due to a charge transfer process between compensated boron and ionized donors, which could be recorded before the phosphorescence decayed. This mechanism is also suitable for interpreting the observed phenomenon of this specimen.
Natural diamonds with long-lasting phosphorescence under UV excitation are typically type IIb or chameleon diamonds (J.M. King et al., “Characterizing natural-color type IIb blue diamonds,” Winter 1998 G&G, pp. 246–268; T. Hainschwang et al., “A gemological study of a collection of chameleon diamonds,” Spring 2005 G&G, pp. 20–35). It is rare to find diamonds of other types, especially type IaB diamonds, showing this phenomenon. Finding a detectable, if temporary, B0 defect in a type IaB diamond is also unusual. @chapter:11


Publication Year: - Title: An Archive of Excellence: The Richard T. Liddicoat Gemological Library Celebrates 25 Years Abstract: The Richard T. Liddicoat Gemological Library and Information Center at GIA's world headquarters, The Robert Mouawad Campus, in Carlsbad, California. Photo by GIA

                      700+ periodicals
1,800+ videos
57,000+ books
150,000+ photographs

The sheer magnitude of print, video and image resources available through the Richard T. Liddicoat Library and Information Center is astounding. From 31 different editions of philosopher Pliny's “Natural History” – including a copy published in 1496 – to George Frederick Kunz’s “Gems and Precious Stones of North America,” one of the most important works on gems, the library houses some of the rarest and most highly regarded books in gemological and jewelry history. What started humbly as a single bookcase has become the largest, most complete repository of its kind in the world and the first point of reference for those studying gems and jewelry.

GIA’s original library consisted of a handful of publications that GIA founder Robert Shipley loaned to students and staff. Over the years, the collection grew to include important books about gems and jewelry, trade journals and the latest gemological research, totaling 2,500 informally cataloged and stored volumes by 1980.

Richard T. Liddicoat, then-president of GIA, recognized the need and benefit of more professional attention to the Institute’s growing collection. He appointed Dona Dirlam, a diamond grader and former geology teacher, as librarian. Dirlam embarked on a decades-long effort to develop the library into the resource it is today. She began by opening the library to students and staff without an appointment, reorganizing and cataloguing the collection, and expanding the physical space and the staff.

“We needed more staff by the mid-1980s just to handle the growing number of phone calls requesting information,” said Dirlam. “The more you help people, the more they call back for help, and then tell other people.”

As more and more people outside the Institute learned about the indispensable resources available, the library continued to grow, and so did the importance of amassing a comprehensive collection.

GIA acquired the Sinkankas collection, which contains nearly every major work related to the study of gems and jewelry, in January 1988. Accumulated over 40 years by noted author and lapidary John Sinkankas and his wife, Marge, the collection added nearly 6,000 articles and 10,000 books, including works dating back to 1511 A.D., rare volumes and numerous editions in different languages. With the addition of the Sinkankas collection, the library became a resource unlike any other.

GIA held an inaugural celebration in August 1989 to formally dedicate the library to Liddicoat, the ‘Father of Modern Gemology,’ and to officially unveil the Sinkankas collection.

Nearly 300 guests attended the event, described by George Schuster in his 2003 book “Legacy of Leadership: A History of the Gemological Institute of America:”

August 21, 1989. It was a glittering summer night of champagne, laughter and honors, a black-tie evening of men in tuxedos and women in elegant gowns. It was a night important enough to attract hundreds of leading gem and jewelry industry figures to the Gemological Institute of America.

It was the night of the formal dedication of the Richard T. Liddicoat Gemological Library and Information Center, including the newly acquired, world-renowned Sinkankas collection.

It was the night of the official unveiling of what one writer called “the greatest collection of gemological literature ever assembled.”
…

During the official opening ceremony, guests heard firsthand accounts from Dirlam, Liddicoat, and Boyajian on the acquisition of the Sinkankas collection and what it meant to GIA and the gemological community. Another highlight was Sinkankas’s off-the-cuff comments on how he and Marge had created their personal library, including book-buying adventures in Europe, the Howes acquisition and his longtime relationship with GIA. Mayor James Conn presented [then-president] Bill Boyajian with a letter of commendation from the city of Santa Monica acknowledging GIA’s contribution to education in the community. At the end of the night, departing guests were handed reprints of Gems & Gemology’s Spring 1989 article on the Sinkankas collection.

Now, 25 years later, GIA’s library continues to grow and offer resources to the gem and jewelry industry, gem enthusiasts, students and the public. Library staff assisted more than 10,000 visitors, students and staff in 2013. It’s open to the public Monday through Friday, but you don’t have to be in California to take advantage of its resources. Experienced librarians also answer questions and offer reference for gem- and jewelry-related questions by email, mail, phone and fax, responding to more than 1,000 queries each year. You can also search the library catalog online and access all 80 years of Gems & Gemology, GIA's quarterly research journal, on the website.

For Dirlam, the goal of the library is simple.

“We want to make this library the archive of the international jewelry industry, and an important part of our mission to ensure the public trust in gems and jewelry.” @chapter:22


Publication Year: 1994 Title: Summer 1994 G&G Lab Notes Abstract: Diamond Laser Drill Holes or Natural Inclusions?
Diamond with Unusual Color Zoning
Trapiche Emerald from a New Locality
Jadeite with Metallic Inclusions
Round and Near-Round Freshwater Tissue-Nucleated Cultured Pearls
Glass-Coated Quartz
Synthetic Sapphire with a Small Star
Sapphires from Yogo Gulch, Montana
Dyed and Impregnated Turquoise
Faceted Vayrynenite

To view the full section, download the PDF above. @chapter:17


Publication Year: 2015 Title: Books: I Love Those Earrings: A Popular History from Ancient to Modern Abstract: By Jane Merrill with Chris Filstrup, 224 pp., hardcover, illus., publ. by Schiffer Publishing, Ltd., Atglen, PA, 2014. US$59.99.

              Earrings have proven to be a cultural touchpoint through the ages, treasures that transcend time and social value. Mythological characters depicted in Renaissance paintings and Hollywood legends like Catherine Deneuve wear them, as do Barbie dolls and pirates. In her inappropriately scaled and produced compendium, Jane Merrill traces the Western timeline of earring history. From the ancient Dacians to the modern era, she unwinds the cultural value of these portable jewels and adds a lively dash of pop culture.

Merrill’s is a wonderful viewpoint, one that offers a fresh translation of the history of jewelry. She pays special attention to the context and significance of earrings and other jewelry, often working from an art historian’s perspective. She covers an impressive expanse of time and geography with a collection of observations and stories arranged chronologically in an effort to humanize a subject that’s often associated with royalty and fame. Merrill mixes her own cultured experiences with those of the noble and storied to link ordinary people with celebrities and goddesses.

As virtuous as this inspired ambition may be, the message presented in the title and summary of the book does not play out in harmony. Merrill’s introductory invitation to “…raid the jewelry boxes of the prestigious and the more representative women of history…” suggests an exclusive, and visual, view of famous collections, a private and privileged peek into the boudoirs of queens and dressing rooms of movie stars. Disappointingly, this happens only once, with the inclusion of one painting of Jane Stanford’s auction collection, circa 1898.

By title and summary alone, the reader might also expect to find impressive photography of famous pairs of earrings, large in size and with great resolution. This is not the case. Most images are smaller in scale and arranged and captioned irregularly. Images that would support the text are not shown. Several stories would benefit from a series of timelines or maps, but these are not included.

Similarly, the format and layout are not representative of the sentiment and scholarship inside. While the percentage of white space on each page, the paper, and the printing quality promise vibrant, large-scale images and precise editing, this is not what is found within the pages. The background color of excerpts (light pink) is irritating at best, and worse, oversized images of earrings are often partially hidden by these dedicated boxes.

The most memorable musings and thought-provoking examinations in the book include the dynamic statements and comprehensive reflections throughout, such as the powerful call to recognize how meaningful earrings, like all pieces of jewelry, are. There’s plenty of evidence that they have been crafted, worn and celebrated the same way for thousands of years. Additionally, Merrill’s personal stories, those about her coauthor Chris Filstrup and the collection of prose and poetry at the end of the book—dedicated to lost earrings and lost loves—are the most memorable moments of the text. These high points and intriguing theories would have been better served by a revised title, theme, and size. @chapter:16


Publication Year: 2000 Title: Gemstone Enhancements and Detection in the 1990s Abstract: Gemstone enhancements and their disclosure became the most important gemological issue for the jewelry trade in the 1990s. Growing public awareness of treatments and the greater use of sophisticated technology to enhance the color and/or apparent clarity of gem materials brought to the forefront the need to maintain (or in some cases regain) the consumer confidence that is so vital to this industry. The treatments with the greatest impact were those that affected the gems that were commercially most important: heat and diffusion treatment of ruby and sapphire, “oiling” of emeralds, and fracture filling of diamonds. At the end of the decade, the decolorization of diamonds by high pressure and high temperature posed one of the greatest identification challenges ever faced by gemologists worldwide. Yet most other gem materials were also subjected to enhancements—ranging from traditional processes as with quench-crackled quartz to novel “impregnation” techniques such as the Zachery treatment of turquoise. This article discusses the treatments that were new or prominent during the ‘90s and suggests methods for their detection. @chapter:29


Publication Year: - Title: Filigree Inlay Art: The Intangible Cultural Heritage of China Abstract: This filigree inlay brooch displays some very complicated filigree work on the insect’s head. Inlay work was used to mount the stone to the body. Photo by Eric Welch/GIA.

                      The art of filigree inlay, also called “fine gold art,” combines two craft skills. One is filigree, which includes such techniques as nipping, plaiting, jointing, piling, filling, and knitting, and uses gold or silver threads of different weights. The second component, inlay work, involves mounting the stones to the final product and carving or filing the precious metals. The craftsperson can use one or both skills when creating a piece.

	History of filigree inlay art
Filigree inlay art originated in the Warring States Period (475-221 BC). At the time, it was called “Jin Yin Cuo,” which involved painting gold and silver on the surface of bronze artworks. With the development of techniques for making thin gold and silver thread, which occurred around the Tang (618-907) and Song (960-1279) dynasties, filigree inlay art advanced in maturity.

The Ming dynasty (1368-1644) was the golden age of filigree inlay art. Many masterpieces were created and inherited. Following the Ming dynasty, filigree inlay art reached its peak in the Qing dynasty (1644-1911). Qing was the last dynasty in China’s history. However, it was ruled by the minority group “Man” for over 260 years.

The art form developed by inheriting essential elements from the previous dynasties and adding new elements over time. Many filigree inlay pieces seen in a private art museum run by the premium jade jewelry brand, Zhaoyi, are replicas of masterpieces from Ming and Qing dynasties.

For a long time, filigree inlay artwork was controlled and appreciated only by royal families and the imperial class. Ordinary people were able to afford some products, but were prohibited from owning pieces bearing certain themes like the dragon and phoenix. Only the royal class could own the highest-quality materials and designs.

Social catastrophe at the end of the Qing dynasty meant the imperial family could no longer hold its position and afford luxury items. Many master goldsmiths escaped the palace to open their own businesses. For a while, many small-scale filigree inlay art studios and workshops were concentrated in southern Beijing, which once had been an area full of all kinds of craftspeople.

	This pair of earrings is a replica of a Ming dynasty masterpiece. The earrings are 3-D replicas of lamps used in the Forbidden City. The lamps imitate pavilions with hexagonal profiles. Goldsmiths added seven spherical pendants to the pavilions. When the wearer moves, the pendants swing back and forth. Photo by Eric Welch/GIA.

	This is a replica of a Qing dynasty ring, once used as a gift from the mother-in-law to the new daughter-in-law, expressing wishes that she become a smart wife who benefits the family economically. By applying fine gold art, each small bead on the abacus can move freely. Photo by Eric Welch/GIA.
By the end of the 20th century, after the many social upheavals China had experienced over the previous 150 years, filigree inlay art was one of many cultural heritages that were fading away. Very few master goldsmiths were still able to work in this art form, and young people rarely devoted themselves to the diligence and hard work required. Another barrier came from the Cultural Revolution (1966-1976), when wearing or owning jewelry or simply being pretty was considered offensive.

The drafting, internationally, of the concept of Intangible Cultural Heritage in the early 2000s made it possible for filigree inlay art to be picked up and passed along to future generations. (The concept of Intangible Cultural Heritage encompasses practices, knowledge, and skills that are recognized as part of a country’s or community’s cultural heritage.)

	Collaboration between modern jewelry company and
	master goldsmith
Due to the outrageously high costs required for creating art pieces with filigree inlay art, very few people wanted to invest the money to start from scratch. At this critical moment, the collaboration between Zhaoyi and master goldsmith Bai Jingyi caught people’s attention. Before this collaboration, Master Bai had refused invitations from many jewelry companies due to conflicting interests. President Wang from Zhaoyi reassured Master Bai that making fast and major profit on filigree inlay art was not the company’s goal.

Zhaoyi, which began as a brand that specialized in jadeite, decided to contribute to the continuation of this almost-lost art. This time, Master Bai agreed and they established her studio about four years ago. Zhaoyi also supported Bai’s idea of developing the skills first and then creating some originally designed products.

	Zhaoyi, a famous premium jadeite brand, collaborated with Master Bai to create a filigree inlay art studio. The company uses profits from the jadeite business to support the haute couture filigree inlay art business. Photo by Pedro Padua/GIA.
For the past four years, Master Bai has spent most of her time teaching new artists and young apprentices, making replicas of famous historic pieces, and creating new designs using traditional skills. In Zhaoyi’s Beijing Xin Tian Di guild store, with its three-story layout, two levels are used to display filigree inlay art replicas and new designs. Located on the third floor is the only private filigree inlay art museum in Beijing. Numerous masterpieces from Bai’s studio are displayed there. As Master Bai and her colleagues are making progress on passing this craftsmanship along to the next generation, they are also working on creating new products to fit the high-end jewelry market in China.

	In her studio, Master Bai works on a piece of fine filigree art. Courtesy of Zhao Yi Xin Tiandi Co., Ltd.

	Master Bai Jingyi
After working as a goldsmith and designer in the filigree inlay industry for over 50 years, Bai expressed her deep love for this art style to some contributors.

Her family is made up of the “Man” minority, who formed China’s Qing dynasty. Influenced by her family tradition, she had fallen in love with painting when she was a little girl. Once, she dreamed of becoming a famous painter, but this dream did not come true due to different circumstances and life-changing opportunities she experienced later in her life.

	Master goldsmith and chief designer Master Jingyi Bai creates filigree inlay art and trains others to carry on its traditions. Courtesy of Zhao Yi Xin Tiandi Co., Ltd.
Other than painting, Bai was also very interested in pattern design. This provided a good basis for her entire design life. As a precious-metal major in school, she gained some of the needed knowledge and skills to make artworks like filigree inlay, enamel, etc., but she felt those skills were not enough to make her a successful master goldsmith and designer. She made the most progress after she started working in a real filigree inlay art factory and was trained by some older-generation master goldsmiths.

For the past 50 years, Bai has devoted herself to the tradition and development of filigree inlay art, receiving numerous honors and achievements. In 2008, the state council officially named filigree inlay art as the Intangible Cultural Heritage of China. Master Bai was selected to be the official Representative Inheritor at the same time. This honor and its responsibilities, plus her collaboration with Zhaoyi, brought her career to new heights.

With support from the company and her colleagues, Bai made many famous replicas of historic filigree inlay art pieces. One example is the “Six Dragon and Three Phoenix Crown.” She and her colleagues applied not just fine gold art to this piece. She also applied another almost-lost skill called “kingfisher feather skill.” The kingfisher is a beautiful bird with feathers on its back displaying very attractive and lively blue color. Old craftsmen pulled the feathers off a living bird and then mounted them in different jewelry pieces. It was an art used mostly by the Imperial family. In 2012, the “Six Dragon and Three Phoenix Crown” masterpiece was named the Beijing Arts and Crafts Treasure.

	Details were created using the ancient kingfisher feather skill on this “Six Dragon and Three Phoenix Crown” masterpiece. Photo by Eric Welch/GIA.
Now, Master Bai still works full time in her studio as the chief designer for Zhaoyi’s filigree inlay art haute couture services. She is pleased to see more and more young people joining her as apprentices to inherit this old but exquisite art. She expresses pride in them and tries her best to pass those skills on to the next generation.

	Master Bai still works full time at the studio, and also teaches students and apprentices. Courtesy of Zhao Yi Xin Tiandi Co., Ltd.

	The market for filigree inlay artwork
Although Master Bai and her group focus mainly on the filigree inlay art high-end market, she admits that there are two parts of the market as a whole. Many small-scale workshops around the country have limited investment levels and different interests. Their goal is not to inherit or pass the skills along to the next generation, but rather to make some quick money with relatively low-quality filigree inlay works, or add some filigree elements to other rapidly made products. These products dominate the souvenir market.

Master Bai originally thought that her high-end products would only be consumed by successful businessmen or older-generation high-ranking government officials. To her surprise, some young people are highly motivated to buy her creations as well. One of the studio’s first individually designed jewelry sets was purchased by a very young couple.

In terms of domestic and overseas markets, Master Bai does not see much difference between them because “going back to traditions” seems like a non-stop trend in the fashion world. She has noticed that China’s young people are paying more and more attention to their traditions. She enjoys seeing young girls wearing fashion outfits with traditional jewelry pieces inherited from their mothers or grandmothers. As for overseas consumers, in addition to paying attention to the style, they also focus on the craftsmanship of a piece. Overall, the market outlook for filigree inlay art is very bright.

	These newly designed modern filigree inlay art pieces are displayed in Zhaoyi’s art museum. Photo by Eric Welch/GIA.

	The future of filigree inlay art
As an Intangible Cultural Heritage of China, filigree inlay art has caught people’s attention and is being protected and passed along. Although there is hope in China of keeping this ancient art style and skill alive, there are some difficulties that can’t be avoided. First of all, there are fewer and fewer master goldsmiths. As time goes by, some skills will gradually be lost. More teachers are needed to pass knowledge and skills along to young people.

Secondly, more young apprentices are needed to inherit this art style. Some college graduates want to sit down and learn the skills, but to make sure there are enough people to inherit these skills and pass them along to the next generation, a larger inheritors’ pool is needed.

Last but not least, any type of art can be kept alive only when it can breathe on its own, which means it has to be alive in the real market, not just residing in some museums or appreciated by only a small group of people. Bai insists that even though the creation of replicas is necessary for picking up the almost-lost skills, she and her group will have to make modern designs that can be easily accepted by the current market and its consumers. This will result in keeping the art alive.

What Master Bai wants to tell young jewelry designers is that they need to absorb inspiration from both modern art and Chinese cultural traditions. As a big fan of western oil painting, Bai recommends that art students who want to be jewelry designers go overseas to learn modern art concepts and western artistic aspects. She also reminds them to not forget their own traditions, since that can distinguish them from others. As she says, the friction between western art and oriental tradition usually creates the most beautiful fireworks. @chapter:21


Publication Year: 2017 Title: Synthetic Moissanite Imitating Rough Diamond Abstract: Figure 1. A very light green 9.71 ct synthetic moissanite crystal, submitted to the Carlsbad laboratory as a rough diamond. Photo by Rebecca Tsang; field of view approximately 14 mm.

The Carlsbad laboratory recently examined a very light green 9.71 ct specimen (figure 1), measuring 11.79 × 9.69 × 11.61 mm, that was submitted as a rough diamond. The sample resembled a diamond octahedron, with surface growth features and a bright vitreous to subadamantine luster. Closer examination of its habit and surface features, along with gemological and advanced testing results, revealed it to be a synthetic moissanite.

The specimen was not a true octahedron, as is typical of a diamond crystal, but a rectangular bipyramid with 10 faces (eight triangular and two hexagonal side pinacoids on the girdle). The surface was dimpled, and two of the faces had deep striations resembling growth features in a rough diamond. Irregularly shaped and sub-hexagonal etch pits (figure 2), along with some dark brown residue, were also found on the surface. Due to the uneven surface, observation of internal features was limited to some small scattered pinpoint inclusions and a few etch tubes (figure 3). The surface also made it difficult to see any doubling effect or a doubly refractive reaction in the polariscope. Viewed in plane-polarized light, however, a large twinning plane crossed the crystal diagonally, bluish green on one side and colorless on the other. This dichroism served as proof of the stone’s doubly refractive nature, as opposed to singly refractive diamond. Standard gemological properties of the stone offered further evidence of its true identity, including an over-the-limit refractive index reading, a hydrostatic specific gravity (SG) of 3.23, very weak yellow fluorescence in both long-wave and short-wave UV, and a uniaxial optic figure. These properties and advanced testing results, including Fourier-transform infrared (FTIR) and Raman spectrometry, identified the specimen as synthetic moissanite. It is important to note that although natural moissanite exists, it is extremely rare and gem-quality material has never been found. Natural moissanite commonly occurs in fragmented pieces and in much smaller sizes (the largest known specimen measured 4.1 mm), often with a creamy white or red matrix (Summer 2014 GNI, pp. 160–161). That was not the case for this 9.71 ct synthetic moissanite.

Figure 2. Sub-hexagonal etch pits in synthetic moissanite are observed using differential interference contrast. Photo by Rebecca Tsang; field of view approximately 1.44 mm.

Figure 3. Etch tubes extended from surface etch pits and ended at the twinning plane. Photo by Rebecca Tsang; field of view approximately 2.30 mm.
Gemological and advanced testing are indispensable tools for revealing the true identity of gems, especially simulants and imitations with an appearance that can easily deceive the general public. While there is no evidence that this specimen was deliberately deceptive, gemological knowledge is important in preventing accidental and intentional acts of fraud and preserving the integrity of the trade. @chapter:32


Publication Year: 2017 Title: Colorful Chatoyant Glass Abstract: Starburst Stone is a colorful new devitrified glass, reminiscent of the product once marketed as Victoria Stone. Photo by Kevin Schumacher; courtesy of Australian Rough and Tumble.

This year at the Tucson gem shows, this author encountered an interesting new product of chatoyant devitrified glass (glass that has converted to a crystalline material) marketed as “Starburst Stone.” This material (see above) closely resembles the chatoyant glass known as Victoria Stone, which was developed in Japan by Dr. Satoyasu Iimori in the 1950s and produced for almost 40 years (http://victoriastone.sakura.ne.jp/JP-30-88-B.pdf).

John Bennett, in partnership with Artur Birkner (both based in Perth, Western Australia), began developing Starburst Stone in 2013, and this is the first year of commercially available production (approximately 100 kilograms). This devitrified glass is made from a chemical mixture that is cooled at a rate to facilitate nucleation and growth of dense networks of elongate lath-like crystals, and each batch of glass is colored by the addition of certain metals. Darker blues are achieved by adding cobalt, lighter blue by adding copper, and green by adding chromium to the glass mixture.

Standard gemological testing revealed properties consistent with manufactured glass. The RI was between 1.51 and 1.52 and varied slightly between the different colors tested. The average SG, measured hydrostatically, was 2.62. Raman analysis identified the devitrification product responsible for the chatoyancy as apatite, which was also responsible for the chatoyancy in the devitrified glass product known as Victoria stone.

Dark and light blue, green, and golden Starburst Stones are being manufactured, with additional colors in development. This new ornamental glass showing chatoyancy is a welcome addition to the gem trade. Those interested in the material once sold as Victoria Stone will certainly appreciate this very similar phenomenal glass product. @chapter:12


Publication Year: 2016 Title: Dyed Green Beryl Abstract: Figure 1. A green dye concentration in beryl was observed along fractures and confirmed by spectroscopic testing. Photo by HyeJin Jang-Green.

Emerald simulants and synthetic emeralds have often been submitted for testing to GIA (e.g., Spring 2001 Lab Notes, pp. 57–59). Recently, the New York laboratory examined a dyed green beryl that was intended to imitate natural emerald. The green octagonal step-cut stone, set in a yellow metal ring with near-colorless stones, initially appeared to be emerald.

The stone had a refractive index of 1.588–1.595 and fluoresced a very weak chalky yellow under long-wave UV radiation and a weak chalky yellow under short-wave UV. Microscopic examination revealed the obvious presence of a green dye concentration in numerous fractures (figure 1) and other natural beryl inclusions such as short needles, particles, and jagged fingerprint patterns. This dyed green material also enhanced the clarity of the stone.

In addition, dyed bands (~610 and 660 nm) were revealed in the visible spectrum by utilizing a high-resolution visible spectrometer (figure 2). The green color in this sample was caused by an organic dye rather than chromium or vanadium elements that give rise to a green color in natural emeralds. When the color was observed under a diffused light source, it became apparent that a near-colorless natural beryl was the starting material. This example shows the importance of spectroscopic testing to confirm the cause of an emerald’s color.

Figure 2. In the beryl’s Vis-NIR absorption spectrum, dye bands were observed at ~610
and 660 nm, while sharp Cr-related features were absent. @chapter:9


Publication Year: 2014 Title: Bumble Bee “Jasper” from Indonesia Abstract: Figure 1. This Bumble Bee “jasper,” measuring 32 × 54 mm, is a mixture of volcanic lava and sediment. Photo by Robert Weldon/GIA; courtesy of Robert E. Kane.

              At the Tucson Gem and Mineral Show, All in Vein (Quartzsite, Arizona) exhibited slabs and pairs of Bumble Bee “jasper,” which was sold elsewhere at the show as Eclipse “jasper.” The term jasper is a misnomer, as this vibrantly colored orange, yellow, and black material (figure 1) actually formed from a mixture of Indonesian volcano lava and sediment. A carbonate-rich rock first discovered on the island of Java during the 1990s, the material is soft, with a Mohs hardness of 5 or below. The porous rock is easily cut and polished, and most specimens are filled with Opticon (H. Serras-Herman, “Bumble Bee ‘jasper’: A colorful volcanic lapidary material,” Rock & Gem, Vol. 43, No. 8, pp. 26–29). @chapter:3


Publication Year: - Title: Geo-Literary Society Explores Diamond Cut Abstract: At the February 2014 annual meeting of the Geo-Literary Society in Tucson, speakers Al Gilbertson (left) and Scott Sucher (right) discussed the evolution of diamond cutting.

                      The Geo-Literary Society held its annual meeting on Friday, Feb. 14 at the Tucson Convention Center. The event, which drew attendees from the Tucson Gem and Mineral Shows, featured presentations by Scott Sucher and Al Gilbertson in a session titled “The Evolution of Diamond Cutting.”

Sucher, president of The Stonecutter in Albuquerque, New Mexico, has created replicas of famous diamonds for more than 30 years. Gilbertson, a research associate at GIA in Carlsbad, California, has authored numerous articles on diamond cut and grading, as well as the 2007 book American Cut: The First 100 Years.

Sucher opened the session by chronicling the early history of diamond use, global trade patterns, and advances in cutting techniques and styles (see table). Using computer models, he compared the brilliance and fire of several early diamond cuts.

Table: Milestones in the early history of diamonds and diamond cutting

				ca. 1000 BC

				First archeological evidence of diamond as a cutting tool

				ca. 300 BC

				Early Indian manuscript discusses the qualities of diamond

				50 AD

				Pliny’s description of diamond use in engraving and jewelry

				1200s

				Development of the point cut (an octahedral crystal with polished faces); arrival of Indian diamonds in Europe’s royal inventories

				Early 1300s

				Establishment of cutting centers in Antwerp, Venice, and Amsterdam

				Mid 1300s

				Development of the table cut, a point cut with its top portion cut off to create a table-like surface

				Late 1300s

				Development of the single cut, a table cut with additional facets on the corners

				1400s

				Advent of the polishing wheel (scaife), and the discovery of cleaving as a faster way of shaping diamond

				1500s

				Improvements to the scaife, allowing polishing speeds of 1000 rpm

				1600s

				Development of the Mazarin, a double-cut brilliant

				1700s

				Development of the Old Mine cut, and the cutting of the famous Wittelsbach (prior to 1664) and French Blue (1671–1673) diamonds

Gilbertson picked up the story with the discovery of Brazilian diamond deposits around 1725, which ushered in a period of glittery excess among European elites. David Jeffries, whose 1750 treatise described the use of a handheld “prover” to measure cutting angles, coined the term “round brilliant” for a cut that contained 58 facets.

The discovery of massive diamond deposits in South Africa in 1867 changed the course of the industry, making these treasures available to a mass market. By 1870, there were 10,000 cutters in Europe. These artisans followed the shape of the original crystal and kept as much of the original weight as possible.

But the emphasis on weight retention was beginning to unravel thanks to Henry Morse, who had set up a cutting shop in Boston around 1860. Morse, who once said, “Shopping for diamonds by the carat is like buying a racehorse by the pound,” emphasized the cut of a stone and the brilliance that resulted. He invented a gauge to measure crown and pavilion angles, and devised his own set of best proportions. He also helped develop mechanical bruting, which increased the production of round-cut diamonds.

With turn-of-the-century improvements such as the circular saw, which made it easy to cut two diamonds from a rough crystal, the stage was set for the modern round brilliant. In 1919, Belgian engineer Marcel Tolkowsky published a landmark book titled Diamond Design, in which he asserted that the best-cut stones feature a 53% table, 59% total depth, and a knife-edged girdle. With some modifications to Tolkowsky’s proportions—an extended lower half, a larger table, and a closed-up culet—the round brilliant as we know it was established by 1950.

As Gilbertson pointed out, the breakthroughs in diamond cut planning and evaluation were just beginning. The Firescope viewer, developed in 1986, allowed the user to see a “Hearts and Arrows” pattern in a diamond cut to these “ideal” proportions. The Sarin scanner, introduced six years later, offered rapid, accurate proportion measurement, which led to the various cut grading services available today. Among other recent advances are inclusion-mapping software and high-speed laser cutting.

Following the presentation, Sucher invited the audience to view his faceted replicas of Cullinans I and II, the Koh-i-Noor, the Hope, and several other historical diamonds.

“Scott Sucher transported us to the early days of diamond cutting as we learned the first sources and tools,” said Dona Dirlam, the Geo-Literary Society’s secretary and the host of the session. “We saw how cutting styles evolved with improvements in the tools and an increase in the diamond supply. With each development, we saw this fascinating transformation through visual models.

“Al Gilbertson told us the largely unknown story of Henry Morse and chronicled the birth of the modern round brilliant,” Dirlam added. “As Al and Scott pointed out, today’s computer-optimized diamond cutting seems light-years removed from the earliest techniques.” @chapter:24


Publication Year: 2018 Title: Gem Characterization Abstract: Figure 1. Measuring about 7 cm across, this 404.2 ct rough from Angola’s Lulo mine is a good example of the irregular shape and surface texture associated with CLIPPIR diamonds. The unusual characteristics of diamonds like this one are the result of formation in a unique geological setting. Once cut, this rough yielded a 163.4 ct flawless D-color diamond. Photo by Jian Xin (Jae) Liao.

The Formation of Natural Type IIa and IIb Diamonds
Evan M. Smith and Wuyi Wang
GIA, New York
Many of the world’s largest and most valuable gem diamonds exhibit an unusual set of physical characteristics. For example, in addition to their conspicuously low nitrogen concentrations, diamonds such as the 3,106 ct Cullinan (type IIa) and the Hope (type IIb, boron bearing) tend to have very few or no inclusions, and in their rough state they are found as irregular shapes rather than as sharp octahedral crystals. It has long been suspected that type IIa and IIb diamonds form in a different way than most other diamonds.
Over the past two years, systematic investigation of both type IIa and IIb diamonds at GIA has revealed that they sometimes contain rare inclusions from unique geological origins. Examination of more than 130 inclusion-bearing samples has established recurring sets of inclusions that clearly show many of these diamonds originate in the sublithospheric mantle, much deeper in the earth than more common diamonds from the cratonic lithosphere. We now recognize that type IIa diamonds, or more specifically, diamonds with characteristics akin to the historic Cullinan diamond (dubbed CLIPPIR diamonds), are distinguished by the occurrence of iron-rich metallic inclusions. Less frequently, CLIPPIR diamonds also contain inclusions of majoritic garnet and former CaSiO3 perovskite that constrain the depth of formation to within 360–750 km. The inclusions suggest that CLIPPIR diamonds belong to a unique paragenesis with an intimate link to metallic iron in the deep mantle (Smith et al., 2016, 2017). Similarly, findings from type IIb diamonds also place them in a “superdeep” sublithospheric mantle setting, with inclusions of former CaSiO3 perovskite and other high-pressure minerals, although the iron-rich metallic inclusions are generally absent (Smith et al., 2018). Altogether, these findings show that high-quality type II gem diamonds are predominantly sourced from the sublithospheric mantle, a surprising result that has refuted the notion that all superdeep diamonds are small and non-gem quality. Valuable information about the composition and behavior of the deep mantle is cryptically recorded in these diamonds. CLIPPIR diamonds (figure 1) confirm that the deep mantle contains metallic iron, while type IIb diamonds suggest that boron and perhaps water can be carried from the earth’s surface down into the lower mantle by plate tectonic processes. In addition to being gemstones of great beauty, diamonds carry tremendous scientific value in their unique ability to convey information about the interior of our planet.
REFERENCES
Smith E.M., Shirey S.B., Nestola F., Bullock E.S., Wang J., Richardson S.H., Wang W. (2016) Large gem diamonds from metallic liquid in Earth’s deep mantle. Science, Vol. 354, No. 6318, pp. 1403–1405, http://dx.doi.org/10.1126/science.aal1303
Smith E.M., Shirey S.B., Wang W. (2017) The very deep origin of the world’s biggest diamonds. G&G, Vol. 53, No. 4, pp. 388–403, http://dx.doi.org/10.5741/GEMS.53.4.388
Smith E.M., Shirey S.B., Richardson S.H., Nestola F., Bullock E.S., Wang J., Wang W. (2018) Blue boron-bearing diamonds from Earth’s lower mantle. Nature, Vol. 560, No. 7716, pp. 84–87, http://dx.doi.org/10.1038/s41586-018-0334-5
Colored Diamonds: The Rarity and Beauty of Imperfection
Christopher M. Breeding
GIA, Carlsbad, California
Diamond is often romanticized as a symbol of purity and perfection, with values that exceed all other gemstones. However, even the most flawless and colorless natural diamonds have atomic-level imperfections. Somewhat ironically, the rarest and most valuable gem diamonds are those that contain abundant impurities or certain atomic defects that produce beautiful fancy colors such as red, blue, or green—stones that can sell for millions of dollars per carat.
Atomic defects can consist of impurities such as nitrogen or boron that substitute for carbon atoms in the diamond atomic structure (resulting in classifications such as type Ia, type Ib, type IIa, and type IIb) or missing or misaligned carbon atoms. Some defects are created during diamond growth, while others are generated over millions to billions of years as the diamond sits deep in the earth at high temperatures and pressures. Defects may be created when the diamond is rapidly transported to the earth’s surface or by interaction with radioactive fluids very near the earth’s surface. Each defect selectively absorbs different wavelengths of light to produce eye-visible colors. Absorptions from these color-producing defects (or color centers) are detected and identified using the gemological spectroscope or more sensitive absorption spectrometers such as Fourier-transform infrared (FTIR) or ultraviolet/visible/near-infrared (UV-Vis-NIR; figure 1). Some defects not only absorb light but also produce their own luminescence, called fluorescence. For example, the same defect that produces “cape” yellow diamonds also generates blue fluorescence when exposed to ultraviolet light. In some cases, the fluorescence generated by defects can be strong enough to affect the color of gem diamonds.

Figure 1. Visible-NIR spectra reveal the absorptions and corresponding atomic defects responsible for the color in gem diamonds.
With the exception of most natural white and black diamonds, where the color is a product of inclusions, colored diamonds owe their hues to either a single type of defect or a combination of several color centers. More than one type of defect can produce a particular color, however. Table 1 provides a list of the most common causes of color in diamond.

Subtle differences in atomic defects can drastically affect a diamond’s color. For example, isolated atoms of nitrogen impurities usually produce strong yellow color (“canary” yellow diamonds). If those individual nitrogen atoms occur together in pairs, no color is generated and the diamond is colorless. If instead the individual nitrogen atoms occur adjacent to missing carbon atoms (vacancies), the color tends to be pink to red. Rearrangement of diamond defects is the foundation of using treatments to change the color of diamond. Identification of treatments and separation of natural and synthetic diamond requires a thorough understanding of the atomic-level imperfections that give rise to diamond color and value.
Evaluating the Color and Nature of Diamonds Via EPR Spectroscopy
Haim Cohen1 and Sharon Ruthstein2
1Ariel University and Ben-Gurion University of the Negev, Israel
2Bar-Ilan University, Israel
Diamond characterization is carried out via a wide variety of gemological and chemical analyses. An important analytical tool for this purpose is spectroscopic characterization utilizing both absorption and emission measurements. The main techniques are UV-visible and infrared spectroscopy, though Raman as well as cathodoluminescence spectroscopy are also used.
We have used electron paramagnetic resonance (EPR) spectroscopy to compare the properties of treated colored diamonds to the pretreated stones. The colors studied were blue, orange, yellow, green, and pink. The EPR technique determines radicals (atoms with unpaired electrons) and is very sensitive, capable of measuring concentrations as low as ~1 × 10–17 radicals/cm3. The results, shown in table 1, indicate that all the carbon radicals determined are affected by adjacent nitrogen atoms, with the spectra showing a hyperfine structure attributed to the presence of nitrogen. The highest concentration of radicals and hyperfine structures is observed in pink and orange treated diamonds. The results concerning nitrogen concentration were correlated with the infrared spectra, which determine the absorption peaks of the diamonds as well as those of the nitrogen contamination in their crystal structure.

Quantitative Absorption Spectrum Reconstruction for Polished Diamond
Roman Serov (presented by Sergey Sivovolenko)
OctoNus Software, Moscow
Natural diamonds generally exhibit a very wide range of spectra. In polished stones, absorption along with proportions and size define perceived diamond color and thus beauty.
In rough diamonds, the quantitative absorption spectrum (the “reference spectrum” in the context of this article) can be measured using an optical spectrometer through a set of parallel windows polished on a stone, so the diamond can be considered a plane-parallel plate with known thickness.
Polished diamonds lack the parallel facets that might allow plane-parallel plate measurement. That is why polished diamond colorimetry uses one of two approaches that have certain limitations for objective color estimation:

Qualitative spectrum assessment with an integrating sphere. Suppose three diamonds are polished from a yellow rough with even coloration: a round (with short ray paths), a cushion (with high color uniformity and long ray paths), and a “bow tie” marquise (with both long and short ray path areas). The spectra captured from these three stones by an integrating sphere will be completely different because the ray paths are very different. However, the quantitative absorption spectrum will be the same for all three stones, since they are cut from the same evenly colored rough. Therefore, spectrum assessment with an integrating sphere has very limited accuracy and is practical for qualitative estimations only.
Analysis of multiple images of a diamond made by color RGB camera. This method has low spectral resolution defined by digital camera color rendering. The camera has a smaller color gamut than the human eye, so most fancy-color diamonds are outside the color-capturing range of a digital camera.

However, quantitative absorption data is very valuable for:

Color prediction and optimization for a new diamond after a recut process
Objective color assessment and description of a polished diamond

This paper presents a new technology based on spectral light-emitting diodes (LEDs) and high-quality ray tracing, which together allow the reconstruction of a quantitative absorption spectrum for a polished diamond. The approach can be used for any transparent polished diamond. The recent technology prototype has a resolution of 20–60 nm, which is practical for color assessment. Figure 1 (top) presents three photorealistic diamond images: A is based on the reconstructed absorption spectrum collected from a polished diamond, B uses the reference spectrum collected in the rough stage through a pair of parallel windows, and C uses the averaged reference spectrum. Figure 1 (bottom) shows both measured quantitative absorption and reconstructed absorption spectra.

Figure 1. Top: Photorealistic diamond images generated from the reconstructed absorption spectrum (A), the reference spectrum (B), and the averaged reference spectrum (C) of the same stone. Bottom: Quantitative and reconstructed absorption spectra.
This technology has the potential to ensure very close to objective color estimation for near-colorless and fancy-color polished diamonds. The reconstructed spectrum resolution can be enhanced to 10–15 nm in future devices. @chapter:35


Publication Year: 1996 Title: Summer 1996 Gem News International Abstract: Diamonds
            Diamond with a Fluorescent Phantom Crystal
            Tairus Synthetic Diamonds in Jewelry
Colored Stones
            Anorthosite Rock with Uvarovite Garnet "Speckles"
            Update on Porous Chrysocolla-Colored Chalcedony
            Chatoyant Clinochlore from Russia
            Cat's-Eye Diopside from Southern India
            Garnets from Mozambique
            Green-and-White Jadeite from Russia
            Visit to Myanma Gems Museum
            Variegated Translucent Jasper from Mexico
            An Unusual Morganite
            Scottish Pearls
            Rubies from Madagascar
            Sapphire Mining in Kanchanaburi
            Update on Tanzanite Mining
            "Golden" Tourmaline from Kenya
Treatments
            Novel Opal Doublets from Brazil
            Sapphires with "Induced" Stars
Synthetics and Simulants
            Manufactured Composite Material Imitating Jadeite
            "Drusy" Silicon, a Computer-Industry By-Product
            A Convincing Tanzanite Substitute
            "Tavalite," Cubic Zirconia Colored by an Optical Coating
Announcements
            Sixth Annual Cutting Edge Awards
            Gem-Related Exhibits at American Museums
            Special Synthetics Exhibit at the Sorbonne

To view the full section, download the PDF above. @chapter:8


Publication 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! @chapter:0


Publication Year: 2014 Title: Challenges and Opportunities Abstract: Welcome to the second issue of our 80th year!

In June, GIA held a reception at our Carlsbad headquarters to celebrate this anniversary and to honor the artistry of Harold and Erica Van Pelt. The reception marked the opening of a museum exhibition of their G&G cover shots, displayed alongside many of the fabulous pieces they photographed. The Van Pelts’ beautiful images graced the covers of our journal for nearly 30 years, and really symbolized the stature and quality of G&G.

Along with GIA president Susan Jacques, editor-in-chief emeritus Alice Keller, and frequent contributor John King, I was privileged to offer a few words to our guests. While the others spoke to G&G’s context, its place at the heart of GIA’s mission, and the contributions that enriched the journal over the years, my topic was the future. Although there are undoubtedly challenges in living up to G&G’s 80-year legacy, there are corresponding opportunities to take our journal to a much wider audience. While technology and social media provide much of this new potential, it’s also abundantly clear how well people respond to the printed journal, and how important face-to-face contact is for transforming ideas into reality. As we plan for the future, our strategy needs to incorporate both elements.

Our lead article in the summer issue, by GIA’s Robert Weldon and Russell Shor, examines the progress Botswana has made toward becoming a major diamond processing and jewelry manufacturing center. The country has a history—primarily through the rich diamond mines in its territories—of harnessing natural resources for the benefit of its people. The authors examine the current status of Botswana’s cutting industry and its prospects for the future. The article draws from Weldon’s 2013 visit to Botswana with GIA videographer Kevin Schumacher, whose extensive videos illuminate many of the locations and people described in the paper.

In the minds of many practicing gemologists, three-phase inclusions in emerald are inextricably linked to Colombian origin. Yet emeralds from Afghan, Chinese, and Zambian deposits can display strikingly similar multiphase inclusions. Sudarat Saeseaw, Supharart Sangsawong, and Vincent Pardieu, all from GIA’s Bangkok laboratory, present detailed photomicrographs of samples from these localities and combine this study with spectroscopy and trace-element analysis. The authors demonstrate that the combination of these techniques has significant potential for the geographic origin determination of emerald.

We also offer a fascinating paper examining the blue color phenomena seen in some Dominican and Indonesian amber. Yan Liu of Liu Research Laboratories and coauthors Guanghai Shi and Shen Wang provide the gemological basis for the surface-related blue fluorescence seen in such amber.

Our final feature article—also on amber—comes from Yamei Wang and Mingxing Yang, both of the China University of Geosciences in Wuhan, and Yiping Yang, a former postgraduate from the same institution. This paper documents their heat treatment experiments on a range of amber samples, which successfully reproduced some of the products found in today’s jewelry marketplace. Along with the methods and results of their experiments, the authors present criteria for identifying heated amber.

In addition to these feature articles, you’ll find a variety of updates in our regular Lab Notes and Gem News International sections.

One of our continuing priorities is to develop synergy with the GIA website. In this issue, we entreat you to visit—in case you missed them—our recent article posts and related videos. You’ll hear the voices of researchers, miners, and gem professionals, and see inside research institutions, mines, museums, and the diverse locations where gems are bought and sold.

We hope you enjoy the summer 2014 edition! @chapter:28


Publication Year: - Title: Bargaining for Gems in Chanthaburi Abstract: Buyers await sales offers at the teeming Chanthaburi gem market, held every weekend. Many buyers post handwritten signs detailing their wants at the front of the table or on the walls behind them.

                      A middle-aged woman in a floral dress and sun visor zips open a plastic bag and spreads an array of polished rubies across a desk blotter, taking care to keep them in the sunlight, where the colors come through richer. Behind the desk, a bushy-bearded buyer combs through the parcel with his tweezers, setting aside a dozen stones in about as many seconds. The dealer punches a per-carat price into her calculator. The buyer types in a counteroffer, and the two silently bargain until a deal is struck.

At the Chanthaburi gem market in southeastern Thailand, where buyer and seller often speak no common language, the calculator is a universal translator.

	Buyers sort through a prospective parcel of polished ruby at the Chanthaburi market while the runner awaits their offers. For buyers who don’t speak Thai, the calculator serves as the universal translator.
Chanthaburi’s gem trade dates back centuries—accounts of mining and trading there began in the 15th century—and today its gem market remains one of the world’s largest and liveliest.

Thailand is one of the world’s leading colored gemstone cutting and trading centers. It exported an estimated $650 million worth of gemstones during 2012—about half of that sapphire, according to the Gem and Jewelry Institute of Thailand. While most traders keep their export offices in Bangkok, the traditional center of the colored stone industry, the place where nearly all of the cutting is done, is Chanthaburi. This town of about 30,000 lies 150 miles southeast of Bangkok, near the old ruby and sapphire mining area of Pailin on the Cambodian border.

	A buyer checks a large parcel of blue sapphire in the open-air Chanthaburi market while the dealer holds the rest of the lot.
The Chanthaburi gem market is a relatively quiet place during the week, with a few dozen dealer shops on narrow Si Chan Road offering loose gemstones, gold settings, and equipment, such as electronic scales, lighting, and loupes and tweezers. But the weekend is when the market truly comes alive, spilling into the neighboring streets and alleys. Beginning at 10 am Friday, hundreds of dealers from around the country and many parts of the world set up makeshift stands with scales, calculators and, of course, gems. Within 30 minutes, the streets are teeming with buyers, brokers, sellers and an occasional tourist. The trading continues until dusk. Unlike traditional markets, most of the people sitting at the tables and desks are buyers, not sellers.

	Some of the buildings along Si Chan Road are weekend stone exchanges where buyers and sellers don’t have to worry about the sudden downpours that can arrive at any time during the spring and fall.
The center of the action is at the intersection of Si Chan Road and Thetsaban Road, where the streets serve as an impromptu gem exchange. Buyers will find a seat at a table, sometimes posting a sign listing their wants, and wait for brokers or dealers. Runners working with the dealers dash from table to table, taking orders, showing gems and carrying price offers back to their bosses. Some dealers hurry to intercept the buyers before they get to the tables so they don’t have to pay commission to the table owners.

What’s for sale? Not surprisingly, a vast majority of the dealers were offering ruby and sapphire of all colors—some for as little as $2 or $3 per carat. Are treatments disclosed? The price is the disclosure, said one dealer who’d stopped by to show a parcel of ruby. Sellers also showed spinel, various colors of tourmaline, tsavorite and spessartite garnet, and even amethyst and citrine. Between the gem vendors and exchanges is a veritable smorgasbord of street food, with vendors offering noodles, barbecue chicken, mangoes and soup bowls.

	Si Chan Road leads to the gem market in Chanthaburi—the street lamps pay tribute to the main commerce in this city of 30,000 inhabitants.
On the side streets behind the market are dozens of “burners,” operations that apply heat and other treatments to gemstones. Most of these have no sign out front but are well known to the local trade.

Veteran dealers say the trading at the market is quieter than a decade ago. They blame Western governments’ sanctions on Myanmar and the general economic malaise in many key consuming markets. But the market has survived transitions before. Indeed, Chanthaburi’s gem trade has been rejuvenated to some degree by diffusion treatments that can turn unattractive (and unsellable) corundum into low-cost yellow sapphire. Because of this, at least 10 mine sites are now in operation near Khao Ploy Waen and Ban Ka Cha. Additionally, one site produces black star sapphire that is not treated.

	The Chanthaburi province was once a prolific producer of ruby and sapphire. This mine, about 10 miles from the city, is a source of yellow sapphire.
Despite the slower sales, dealers such as the woman in the floral dress believe Chanthaburi will always have a place in the world gem business, because the skills and the infrastructure vital to the industry are still concentrated here. @chapter:28


Publication Year: 1998 Title: Winter 1998 G&G Book Reviews Abstract: “Bulgari”
By Daniela Mascetti and Amanda Triossi, 225 pp., illus., publ. by Abbeville Press, New York, NY, 1996. US$75.00

“Collecting and Classifying Colored Diamonds: An Illustrated Study of the Aurora Collection”
By Stephen C. Hofer, 742 pp., illus., publ. by Ashland Press, New York, NY, 1998. US$300.00

“The Nature of Diamonds”
Edited by George E. Harlow, 278 pp., illus., publ. by Cambridge University Press, New York, NY, 1998. US$29.95 (softbound)

“Glossary of Geology, 4th Edition”
Edited by Julia A. Jackson, 769 pp., publ. by the American Geological Institute, Alexandria, VA, 1997. US$110.00

“Gem and Jewellry Year Book 1997–98”
Edited by V. V. Kala and A. Kala, 697 pp., illus., publ. by International Journal House, Jaipur, India [diaworld@jpl.vsnl.net.in], 1998. US$35.00 (surface), US$50.00 (air)

To view the full section, download the PDF above. @chapter:20


Publication Year: 2016 Title: Ruby and Sapphire from Muling, China Abstract: Figure 1. Muling, the site of an emerging corundum deposit, is located in northeastern China.

	Only a few Chinese sources produce gem-quality corundum, such as Changle, in Shandong province, but sapphires from that location are not considered top quality in the trade because of their dark hues. An emerging deposit in Muling, in northeast Heilongjiang province (figure 1), produces gem-quality corundum comparable to some world-renowned sources. The main deposits are seated in mountain valleys about 70 km from the town center. Corundum was known in Muling as early as 1985; after preliminary exploration, further activity virtually stopped because of technical and logistical limitations. As a result, production has been very limited, and very little information was published about rubies and sapphires from Muling until 1995 (J.X. Sun, “Basalt related to ruby and sapphire in eastern Heilongjiang and reconstruction of paleovolcanic mechanism,” Acta Petrologica et Mineralogica, Vol. 14, No. 2, 1995, pp. 126–132).

	According to Aijun Yi, director of mineral resource administration in Muling, the region has produced large amounts of gem-quality eluvial materials since 1994, including corundum, brownish red zircon, garnet, and spinel (T. Chen et al., “Brownish red zircon from Muling, China,” Spring 2011 G&G, pp. 36–41). As colored stones became more popular in the Chinese gem markets, interest in ruby and sapphire from Muling grew accordingly.

	We acquired a parcel of rubies and sapphires from local miners. The stones ranged from 0.8 to 15.2 ct (figure 2). Most exhibited well-formed tabular hexagonal crystals, though some broken sapphires had a tumbled appearance. The sapphires were pink, yellow, violetish blue, greenish blue, light blue, and deep blue; there were also near-colorless specimens. Most of the rubies and pink sapphires had a purplish component. Samples other than the deep blue material showed high transparency. Rubies and pink sapphires exhibited medium red fluorescence under long-wave (356 nm) UV light and a weak reaction under short-wave (245 nm) UV. Other varieties of sapphire had no reaction under long- or short-wave UV.

Figure 2. Ruby and sapphire rough from Muling exhibited well-formed tabular hexagonal crystal forms; some sapphires showed a tumbled appearance in broken pieces. Photo by Yimiao Liu.

	The samples generally showed abraded features and unhealed fissures, but some were predominantly clean under the loupe and large enough to be faceted. Fourteen stones were fabricated as parallel polished windows for microscopic examination. Several interesting internal features were visible under the microscope. The inclusions, which mainly appeared as rounded single crystals or multiphase syngenetic clusters, were in micron sizes (50–200 µm) and were identified by Raman as feldspar and sillimanite. The latter mineral only occurred as component mineral crystals in a multiphase inclusion. Most rubies hosted whitish needles forming three-dimensional skeleton networks that might be the result of diaspore exsolution (figure 3). Further microscopic observations under polarized light showed characteristic lamellar twining structures in every sample.

Figure 3. A detailed structure of whitish needles forming a three-dimensional skeleton network in a ruby sample. Photo by Yimiao Liu.

	Trace element analysis by LA-ICP-MS showed a Cr content of 173–636 ppma in the pink-red series, accompanied by a significant level of Fe (1650–2510 ppma) and a noticeable level of Ti (36–70 ppma) to add a blue component through Fe-Ti intervalence charge transfer. This explained why Muling rubies and pink sapphires always had a purplish hue. Mg content was about 46–79 ppma, while Ga (13–17 ppma) fell into the expected range for natural corundum.

	Yellow sapphires showed the highest Fe content (4480–4800 ppma); this contributed to their saturated yellow coloration. Iron content was much lower in blue sapphires, along with an appreciable amount of titanium (80–500 ppma) as a blue chromophore. Based on color distribution and transparency, blue sapphires could be grouped as either light blue or deep blue. Most of the light blue sapphires had very high transparency and even color distribution, while deep blue sapphires were less transparent, with hexagonal dark blue color zoning. Among all blue samples, Mg content ranged from 10 to 80 ppma and did not show clear correlation to color, while Ga content (10 to 100 ppma) was noticeably higher than in rubies and pink sapphires.

	At Muling, most rubies and sapphires are found by casual surface digging. Gem-quality corundum usually occurs in eluvial deposits derived from weathered Cenozoic alkali basalts. Unlike other igneous-related deposits known for dark blue sapphires and very limited red material, such as Australia’s Anakie and New England fields (T. Coldham, “Sapphires from Australia,” Fall 1985 G&G, pp. 130–146) and Shandong, China (C. Simonet. et al., “A classification of gem corundum deposits aimed towards gem exploration,” Ore Geology Reviews, Vol. 34, 2008, pp. 127–133), in Muling ruby production was larger than that of sapphire; over 60% of pink sapphires and rubies were high-quality materials.

	In some ways, some Muling rubies have competitive advantages over Mozambique specimens. Their high color saturations and particular internal features (whitish needles forming three-dimensional skeleton networks) resembled those of rubies from Mozambique and might cause confusion in gem markets. On the other hand, blue sapphires from Muling have a pure blue color with no gray component. The variety of colors and the amount of fancy sapphires found in Muling are quite different from sapphires from other classic igneous deposits (see again Simonet et al., 2008).

	At present, the precise location of the Muling gem deposit source rocks has not been confirmed. According to previous geological studies, the area is localized in the northern terminal of the branch of the Tanlu fault (Z. L. Qiu et al., “Trace element and hafnium isotopes of Cenozoic basalt-related zircon megacrysts at Muling, Heilongjiang Province, northeast China,” Acta Petrologica Sinica, Vol. 23, No. 2, 2007, pp. 481–492). The lava in this region can be divided into six volcanic eruption cycles; Muling has experienced three such cycles (Sun et al., 2005).

	Based on mining and geological information and our analysis of Muling rubies and sapphires, we inferred that this material might have originated as xenocrysts from an earlier volcanic eruption and undergone subsequent high-pressure geological processes. These are likely non-classic alkali basalt deposits. Large corundum deposits exist from eastern China to Primorye in far eastern Russia (I. Graham et al., “Advances in our understanding of the gem corundum deposits of the West Pacific continental margins intraplate basaltic fields,” Ore Geology Reviews, Vol. 34, pp. 200–215), but exact locations have not been confirmed.

	Although Muling’s corundum deposit have yet to be mined commercially, the existing production has drawn the attention of Chinese gemologists and gem dealers. The production may rival that from other high-quality deposits, and this source holds great promise for the future. @chapter:0


Publication Year: 2016 Title: Treated Pink Type IIa Diamond Colored by Red Luminescence Abstract: Figure 1. This 4.29 ct type IIa color-treated diamond was graded as Fancy brown-pink under daylight conditions (left) and appeared Fancy purplish gray under incandescent lighting (right). The color change is due to strong NV fluorescence under UV to blue light exposure and irradiation-related GR1 absorption under incandescent illumination. Photo by Robison McMurtry.
Recently, the Carlsbad laboratory received a 4.29 ct type IIa diamond for color origin determination. In daylight-equivalent illumination, the diamond was color graded as Fancy brown-pink, but under incandescent light it appeared Fancy purplish gray (figure 1).

When exposed to long-wave UV light at 365 nm, the diamond exhibited medium orange fluorescence. Based on photoluminescence (PL) spectroscopy, collected using several lasers, it was identified as a treated diamond that had been subjected to high-pressure, high-temperature (HPHT) annealing, irradiation, and subsequent low-pressure annealing. The PL spectra were dominated by the presence of strong NV centers at 575 and 637 nm, along with a strong GR1 peak, confirming the cause of the diamond’s luminescence as the NV centers.

UV-Vis-NIR absorption spectra were collected at room temperature (figure 2) and at liquid nitrogen temperature inside an integrating sphere for this diamond (along with a 0.48 ct treated pink CVD synthetic that does not show the pronounced color change, for comparison). At liquid nitrogen temperature with the diamond under incandescent illumination, the most prominent feature was the GR1 peak creating the purplish gray coloration, comparable to the blue color generated in many irradiated type IIa diamonds. In daylight-equivalent illumination, the emissions of the NV0 and NV– centers were superimposed on the absorption spectrum, thus influencing the diamond’s color within the yellow to red region of the visible spectrum. Color grading of diamonds includes the effect of fluorescence, and therefore the reported color was Fancy brown-pink.

Figure 2. Room-temperature UV-Vis-NIR absorption spectra were collected on the
4.29 ct treated sample (red trace) and a 0.48 ct treated CVD synthetic (blue trace) with
a color grade of Fancy Vivid purplish pink. While NV-related red luminescence caused
a pronounced difference in color for the 4.29 ct sample, it only produced a minor change
in the treated CVD synthetic. In incandescent light (and with minimal influence of the red
luminescence), the synthetic’s color shifted slightly to Fancy Deep purplish pink. The
pronounced absorption from the GR1 peak (550–750 nm) within the 4.29 ct diamond
accounts for the purplish gray color in incandescent lighting.
While treated diamonds have pronounced UV fluorescence due to NV centers, fluorescence spectra collected at a variety of wavelengths show that the NV luminescence is actually stronger when excitation is from blue light (450–500 nm) than from ultraviolet wavelengths, as in the case of this stone (figure 3). This strong emission stimulated by visible light indicates the diamond is colored by red luminescence in response to blue light and, to a lesser extent, by fluorescence due to the UV component in daylight. Other treated pink diamonds, colored by NV absorption, showed similar excitation spectra (Y. Luo and C.M. Breeding, “Fluorescence produced by optical defects in diamond,” Summer 2013 G&G, pp. 82–97). This red luminescence due to NV centers is comparable to the more commonly noted green transmission luminescence from the H3 centers seen in some yellow diamonds. Such yellow diamonds receive greenish color grades due to the visible influence of the green emission on the perceived color in daylight conditions.

Figure 3. These 3-D fluorescence spectra were collected using excitation from the UV
range through the blue range of visible light (320–520 nm). The corresponding
fluorescence spectra show that the relative intensity is much higher when excited by
wavelengths within the visible region than in the UV region. This indicates that red
luminescence excited by visible light is a greater contributor to the pink color than the
UV-activated fluorescence. The 0.48 ct treated CVD synthetic shown in figure 2
demonstrated identical behavior—refer to Luo and Breeding (2016) for comparable
spectra—and indicates that NV-related luminescence contributes to the graded color
in many pink diamonds that are colored by NV centers. The excitation artifact occurs
when the emission spectrometer scans across the excitation wavelength.
For most treated pink diamonds, red luminescence corresponds with and enhances the pink bodycolor (Fall 2011 Lab Notes, pp. 228–229), much like chromium-related red fluorescence enhances the color of rubies. Since bodycolor closely corresponds to luminescence color for most treated pink diamonds, the color difference between daylight and incandescent light sources is minimal. For example, the 0.48 ct treated pink CVD synthetic diamond (figure 2, blue trace) was color graded as Fancy Vivid purplish pink using a daylight-equivalent light and as Fancy Deep purplish pink under an incandescent light. The NV-related emission, excited by the UV to blue light, brightened the diamond in that viewing environment.

The purplish gray bodycolor for this 4.29 ct treated diamond seen under incandescent light derived from the strong GR1 absorption induced by irradiation. The GR1 intensity, as measured by 633 nm photoluminescence spectroscopy and normalized using the diamond Raman peak, was compared with 20 other treated pink diamonds that did not show a substantial color shift. The GR1 intensity of this diamond was 8 times greater than the average value of the 20 treated pink diamonds and 3.5 times greater than the highest value. The GR1 intensity of this diamond was comparable to irradiated green to blue diamonds. In incandescent light, the red luminescence appeared to provide a minimal contribution, as the modifying hue was purplish (implying a reddish component) and not bluish as one might reasonably expect for an irradiated diamond.

Other diamonds have shown a shift in color grade due to appreciable fluorescence. Examples include the 56.07 ct Tavernier diamond, which displays a brown to pink color shift (Y. Liu et al., “The alexandrite effect of the Tavernier diamond caused by fluorescence,” Color Research and Application, Vol. 23, No. 5, 1998, pp. 323–327), and a few type Ib diamonds with a NV-related color shift from greenish brown to orangy brown (Fall 2011 GNI, pp. 234–235).

Some CVD-grown diamonds also have shown a pink to blue color shift, but due to an entirely different mechanism. In those synthetic diamonds, the color change was caused not by a difference in light sources, but by a temporary charge-transfer effect activated by UV exposure. For those CVD synthetics with a high concentration of silicon impurities, UV exposure precipitated a charge transfer between negative and neutral silicon-vacancy centers. In one CVD specimen, the relative concentrations of SiV– and SiV0 were essentially reversed with UV exposure and thus influenced the color change from its stable color of Fancy brown-pink to a temporary Fancy Intense blue (U. D’Haenens-Johansson et al., “CVD synthetic gem diamonds with high silicon-vacancy concentrations,” Conference on New Diamond and Nano Carbons, May 2015, Shizuoka, Japan).

The 4.29 ct natural diamond noted here was HPHT annealed and irradiated to create the NV centers. It appeared to have been irradiated to a far greater extent than most treated pink diamonds, and as a result it had a significantly higher GR1 intensity (as shown in figure 2 and confirmed with 633 nm PL). This accounts for its purplish gray color in incandescent light. The color change between these two attractive colors, along with its large size, makes this diamond quite unusual and serves to illustrate that the color of treated pink diamonds is assisted by red luminescence. This stone also demonstrates that while multiple treatments can provide for some identification challenges, they can also create some truly intriguing products. @chapter:11


Publication Year: 2001 Title: Hydrothermal Synthetic Red Beryl from the Institute of Crystallography, Moscow Abstract: Hydrothermal synthetic red beryl has been produced for jewelry applications by the Institute of Crystallography and an affiliated company, Emcom Ltd., both in Moscow. Diagnostic identification features include: a tabular crystal morphology, chevron-like and subparallel or slightly wavy internal growth zoning, sharp absorption bands at approximately 530, 545, 560, 570, and 590 nm due to Co2+, water-related absorption bands between 4200 and 3200 cm-1 in the infrared spectrum, and the presence of Co and Ni peaks in EDXRF spectra. @chapter:9


Publication Year: 1983 Title: Kashmir Sapphire Abstract: The unique beauty of gem sapphires from Kashmir has brought fame to a locality about which little has been reported in recent years. After an initial burst of activity 100 years ago, the production of these gemstones has slowed to a trickle and the majority of the corundum from these mines today is of industrial grade. Despite evidence of other gem mineral occurrences in the area, difficult terrain and political factors have impeded their exploitation. This article, the result of an expedition to the deposits in 1981, chronicles the history of the Kashmir mines, describes the characteristics of the sapphires found there, and examines the outlook for the future of this area. @chapter:1


Publication Year: 1986 Title: Fall 1986 Gem News International Abstract: Colored Stones
            Green-Fluorescing Emerald from Coscuez
            New Source of Gem Garnets from Idaho
            Blue Pectolite: Trade Name “Larimar”
            Fake Phosphorescent Quartz
            Color Change in Blue Zircon
Synthetics
            Gem-Quality Diamond Crystals
Announcements
            FIT Show in New York
            Iberjoya in Madrid
            Vicenzaoro 1 in Vicenza
            Jewelers International Showcase in Miami Beach
            BIJORHCA in Paris
            Tucson 1987
            INHORGENTA 87 in Munich
            International Fair in Sydney
            Platinum Jewellery Fair in Osaka

To view the full section, download the PDF above. @chapter:20


Publication Year: - Title: Laboratory-Grown Diamonds: Demand Rises, Prices Fall Abstract: This 5.19 ct near-colorless type IIa CVD synthetic diamond is one of the largest faceted CVD synthetics seen at GIA. GIA photo

The proliferation of laboratory-grown diamonds into the market continues to dominate industry news.
A new report says demand for lab-grown diamonds has experienced “significant growth” from attractive marketing, but that prices for such goods have declined 70% in the past two years. The report, compiled by Bain & Co. and published by Rapaport, says the price decline is caused by improving technology that lowered production costs.
The consulting firm also noted that its consumer survey found that demand for lab-grown diamonds falls off sharply when their price tops $1,000 per carat.
Lab-grown producers, other than De Beers/Lightbox, claimed in the report that demand is running above supplies for their products, so prices are not dropping – especially for larger stones that remain difficult to produce.
The Bain view, however, is that prices will likely continue to decline to the point where the two markets “separate themselves,” similar to what happened with colored stones.
NATURAL DIAMONDS
The world’s two largest diamond miners – De Beers and Alrosa – continued cautious supply policies into the first third of the year. Both cut back on rough sales compared to last year, as their clients – diamond manufacturers – complain of softening prices and rising inventories, especially of small, lower quality goods.
The De Beers February/March cycle totaled $490 million, a 13% decline from the same period last year, but the firm held the line on prices after lowering them on some goods last fall. The trade generally welcomed the lower allocations, which include sight sales and individual deals, but claimed that softening polished prices have cut margins.
De Beers production also slid about 10% in 2018 – 32 million cts compared to 35 million cts in 2017 – although revenues increased 4% as the company shifted more of its sales toward higher quality goods.
De Beers noted: “The outlook for 2019 global diamond jewelry consumer demand faces a number of headwinds, including the risk of a potential intensification of U.S.-China trade tensions, the Chinese government’s ability to rebalance economic growth towards consumption, and further exchange rate volatility,”
Alrosa announced that its February rough sales were $340.6 million, up 23% over its January allocation. While the headline stated it was an increase, sales for the first two months of the year were more than 35% below the same period of 2017. The company did note improving demand from some Indian manufacturers, despite “some challenges hampering access to bank financing for the industry.”
KIMBERLEY PROCESS
The United Nations (U.N.) approved a resolution aimed at expanding the mandate of the Kimberley Process (K.P.) to exclude diamonds produced in a climate of “systemic violence” in addition to civil conflicts. This means that diamonds produced in areas where workers and local residents are killed, injured or abused by government, local militia or private security forces may be sanctioned if the measure is adopted. This is a major expansion that can allow, for the first time, diamonds from countries not engaged in civil wars to be excluded by the K.P.
Although the U.N. adopted the resolution and the World Diamond Council approved it, it’s hardly a done deal. The K.P. itself has to adopt the change, and, since that requires unanimous approval from every member country, nothing is guaranteed.
The U.S. tried to push this expansion a decade ago to no avail – it was met with fierce opposition from many African producer countries, particularly those bordering Zimbabwe, who feared reprisals from their larger neighbor. At that time, Zimbabwe’s government was under fire for major human rights abuses at the Marange mining area and assumed (not entirely wrongly) the change in the K.P. was directed at them.
After the U.N. approved the resolution, a coalition of non-governmental organizations (NGOs), The Civil Society Coalition, issued a call to ban diamonds from Zimbabwe based on the fact that the country’s army is involved the mining process. The army violently assumed control of the diamond deposits in 2006 after hundreds of artisanal miners had settled into the area to dig for stones. An estimated 180 people died in the conflict, while human rights abuses allegedly continued for years afterward.
An effort to expel Zimbabwe from the K.P. a decade ago was defeated on the grounds that Zimbabwe’s government was the recognized authority and that sanctions were only applied to rebel groups. @chapter:38


Publication Year: - Title: 2017 Auction Roundup: Pink and Blue Fancy Colored Diamonds Still Rule Abstract: When it sold for $71 million at Sotheby’s Hong Kong in April, the GIA-graded 59.6 ct. Chow Tai Fook Pink Star became the most expensive gemstone ever sold at auction. Photo courtesy of Sotheby’s

More than $1.1 billion worth of extreme top-end diamonds, colored gems and jewelry were sold at auction by the world’s most renowned houses in 2017. While sales results at the two main auction houses, Christie’s and Sotheby’s, were strong, buyers were discerning, especially in the second half of the year when a number of important lots went unsold.

Christie’s sold $556.7 million worth of jewelry worldwide, $8.9 million in online auctions. Sotheby’s did not formally announce its yearly jewelry sales, but a tally of sales from the company's website totaled about $552 million.

The biggest news was the April 4 sale of the Pink Star diamond by Sotheby’s Hong Kong, which set a world price record for a gemstone at auction. The 59.60 ct Fancy Vivid pink Internally Flawless stone was the largest diamond of those grades ever graded by GIA and achieved the record price of $71.2 million. The buyer was Chow Tai Fook, the large Hong Kong-based retail jewelry chain.

The 24.78 carat, Fancy Intense pink, Graff Pink diamond sold in 2010 for more than $1.8 million per carat, which was more than the price per carat sale of the Pink Star in 2017. Photo courtesy of Sotheby's.
While the diamond set a record, it had been sold by Sotheby’s nearly two years earlier for over $83 million. The buyer, however, was unable to come up with the purchase price, obliging the auction house to buy it in for a reported $70 million.
The Pink Star’s record price, however, was a relatively low $1.2 million per carat, which was less than half the per carat cost of similarly graded diamonds offered at auction in recent years. For example, the 24.78 ct Graff Pink sold in 2010 for more than $1.8 million per carat, and the 14.93 ct Pink Promise sold this year for $2.13 million per carat.

The Apollo and Artemis diamonds, twin fancy colored diamonds of 14.54 cts and 16 cts, respectively, sold for $57 million at Sotheby’s Geneva auction in May. Photo courtesy of Sotheby’s
The highest bids throughout the year went, as usual, to large fancy colored diamonds – mostly pink and blue. Both colors were represented in a $57.4 million earring set offered by Sotheby’s at its May 16 auction in Geneva. The 16 ct Artemis Pink, a GIA-graded Fancy Intense pink, sold for $15.3 million, while the 14.54 ct Apollo Blue, a GIA-graded Fancy Vivid blue, went for $42.1 million.

The Pink Promise, a 14.93 ct Fancy Vivid pink diamond sold for $32.16 million at Christie’s Nov. 28 Hong Kong sale. Interestingly, the GIA-graded diamond had been recut from a 16.1 ct Fancy Intense pink. The seller, New York dealer Stephen Silver, told CNN after the sale that he wanted to improve the color grade of the diamond that had been first cut about 15 years ago.

The 14.93 ct “Pink Promise” Fancy Vivid pink diamond sold for $32.16 million at Christie’s November Hong Kong sale. Photo courtesy of Christie's Images.
Christie’s chairman for Europe and Asia, Francois Curiel said it was a strong year overall.

“Trade buyers were more active this past year, but both private collectors and dealers were consistent, active bidders,” he said. Asian buyers remained the “dominant force” in buying top gems, he said, noting that world events, such as the surge of Bitcoin and the unsettled currency markets from Brexit, have not had any noticeable effect on the auction market.

Other fancy colored diamonds sold this year include:

the 19.07 ct Fancy Light pink Le Grand Manzarin, which had been part of the French crown jewels, for $14.5 million
an 8.67 ct Fancy Intense blue, for $13.2 million
a 7.97 ct Fancy Intense blue, for $12.7 million
a twin stone Fancy Vivid blue pair, 3.36 ct and 2.71 ct, for $12.6 million
an 8.8 ct  Fancy Intense pink diamond, flanked in a ring mount by two smaller Fancy blue diamonds, for $9.7 million

And, wrapping up the year, an anonymous buyer paid $15.1 million for a 5.69 ct GIA-graded Fancy Vivid blue diamond at Sotheby’s Dec. 5 auction.

Major colorless diamonds were scarcer on the auction block this year, but two notable gems were sold:

The La Legende, a 92.18 ct heart shaped D Flawless, that drew nearly $15 million at Christie’s May Geneva sale.
The Art of De Grisogono Creation 1, a 163.41 ct D flawless, rectangle cut that was mounted  on an emerald and diamond necklace that sold for $33.7 million, a record price for a colorless diamond at auction. The per-carat price of $209,000 is high for a large D flawless but not a record. The GIA-graded diamond was cut from the 404 carat “February 4” rough found in Angola’s Lulo Mine by Lucapa Diamond Company.

Colored gemstones also attained some extreme, if not quite record high, prices. An Asian buyer paid $10.5 million for a 13.26 ct untreated Burmese ruby on Oct. 3 at Sotheby’s Hong Kong, while Christie’s sold a 15.03 ct untreated Burmese ruby for $12.94 million ($861,000 per carat) at its May Geneva auction.

Provenance, along with a lack of inclusions, helped the 18.04 ct Rockefeller Emerald achieve a record per-carat price of $305,000 at Christie’s New York auction in June. Photo courtesy of Christie’s Images
An old-line name, Harry Winston Inc., paid $5.5 million ($305,000 per carat) for an emerald carrying a lot of history: the 18.04 ct Rockefeller Emerald, offered at Christie’s June 20 New York auction. John D. Rockefeller Jr. purchased this Colombian emerald for his wife, Abby, in 1930.

Jade always tops the gemstone bill at the Hong Kong auctions and, in November, a buyer at Christie’s paid $12.3 million for a jadeite bead bracelet accented with diamonds and a small ruby.

Buyers weren’t in the mood to take everything. The 37.3 ct Fancy Intense pink Raj Pink diamond, offered by Sotheby’s at its November Geneva sale, failed to sell. Bidding started at $10 million, but halted at $14 million, less than half of the high pre-sale estimate. Also, Sotheby’s promoted a 110.92 ct L color VSI clarity diamond as the largest round brilliant ever to come to auction at the Dec. 5 New York auction, but the diamond did not find a bidder willing to meet its pre-sale estimate of $4.2 million.

The Raj Pink, a 37.30 carat GIA-graded Fancy Intense pink diamond did not sell at Sotheby’s November Geneva auction. The stone displays a strong, unmodified pink color and is said to be the largest known Fancy Intense Pink diamond in the world. Courtesy of Sotheby’s
Royal provenance is not a key to an automatic sale. Sotheby’s offered two Fancy Intense yellow diamonds, 102.54 cts and 82.47 cts respectively, at its Nov. 15 Hong Kong auction with a pre-sale price estimate of $9-14 million. The pair of diamonds had belonged to La Pavia, Countess Henckel von Donnersmarck, who in 1851 was married briefly to a Portuguese titled family. La Pavia was a courtesan and hotelier in Paris who eventually married Count Guido Henckel von Donnersmarck, a Prussian industrialist. The diamonds previously sold to a collector for $8 million in 2007, but failed to find a buyer at this sale.

Additionally, a well-publicized 5.15 ct Fancy Deep blue diamond offered Oct. 3 at Sotheby’s in Hong Kong, failed to meet its expected price of $7-9.6 million. @chapter:30