Title: Summer 2018 G&G: Diamonds Across the Spectrum, Byzantine Garnet, and Sapphires from Yogo Gulch Abstract: For more than 120 years, Yogo Gulch in central Montana has been one of the world’s most illustrious sapphire sources. In this issue, Nathan Renfro, Aaron Palke, and Richard Berg offer a mining history and gemological characterization of Yogo sapphires. The cover photo shows a suite of rough Yogo sapphires atop samples of the ouachatite dike rock in which they are found. The largest rough sapphire weighs 8.49 ct. Photo by Kevin Schumacher; courtesy of Don Baide (The Gem Gallery, Bozeman, Montana).

Thanks to notable diamonds such as the Hope and the Blue Moon of Josephine, there is greater public awareness of blue diamonds than any other fancy color. The lead article of the Summer 2018 Gems & Gemology reviews the characteristics of the more than 15,000 blue, gray, and violet diamonds examined at GIA’s labs over the past decade, while another article investigates the color origin of Fancy Dark brown-black diamonds from Marange, Zimbabwe. Other diamond-related content includes a synthetic diamonds chart and a new column about the value of natural diamonds to our understanding of the Earth. The issue also features a study of Japanese bead-cultured pearls from Lake Kasumigaura, traces the origins of an engraved Early Byzantine almandine garnet, and examines the characteristics of sapphires from Yogo Gulch, Montana.
NATURAL-COLOR BLUE, GRAY, AND VIOLET DIAMONDS: ALLURE OF THE DEEP

A few recently discovered blue diamonds are displayed alongside some legendary gems within the blue/gray/violet color range. Clockwise from upper left: the 30.62 ct Blue Heart diamond, photo by Chip Clark, © Smithsonian Institution; a 0.77 ct Fancy Dark gray-violet shield cut, photo by Robert Weldon/GIA; a 1.23 ct Fancy Dark gray diamond, GIA photo; the 45.52 ct Fancy Deep grayish blue Hope diamond and Fancy Deep blue 31.06 ct Wittelsbach-Graff diamond, photo by Robert Weldon/GIA, courtesy of the Smithsonian Institution.
Almost all fancy-color diamonds in the blue/gray/violet range attribute their hue to four main causes, which include structural defects and the presence of inclusions. The Summer issue’s lead article, by Sally Eaton-Magaña, Christopher M. Breeding, and James E. Shigley, reports on these color-causing mechanisms. The authors delve into the gemological characteristics and spectral properties of the 15,000+ natural, untreated blue/gray/violet diamonds examined at GIA’s labs over the past decade.
BLACK DIAMONDS FROM MARANGE (ZIMBABWE): A RESULT OF NATURAL IRRADIATION AND GRAPHITE INCLUSIONS

DiamondView and visible light images of two diamonds that show radiation stains within fractures in the diamond. Non-luminescent regions in the DiamondView images are associated with extensive radiation damage along fractures in the diamonds. Photos and images by Karen Smit.
Graphite-containing diamonds from the alluvial deposits in Marange, Zimbabwe, may be heat treated to yield gem-quality material, but this may create difficulty in distinguishing these specimens from naturally occurring black diamonds. Karen Smit and her coauthors examine the characteristics of a suite of 40 Fancy Dark brown-black diamonds from Marange in order to document the characteristics that would separate them from treated material. The authors uncover various causes of color in these diamonds.
AN EARLY BYZANTINE ENGRAVED ALMANDINE FROM THE GARIBPET DEPOSIT, TELANGANA STATE, INDIA: EVIDENCE FOR GARNET TRADE ALONG THE ANCIENT MARITIME SILK ROAD

Comparison of inclusions in the Early Byzantine engraved gem (left) with garnets from the Garibpet deposit (right). A and B: Inclusion-rich core and inclusion-poor rim with sillimanite fibers at the boundary. C and D: Irregularly shaped ilmenite. E and F: Subrounded quartz crystals. G and H: Large long-prismatic apatite crystal (a) with characteristic graphite inclusions, along with short-prismatic zircon (z) and monazite (m) crystals. Photomicrographs by H.A. Gilg.
An almandine garnet engraved with a Christian stepped-cross motif popular on Byzantine coinage is the focus of this study by H. Albert Gilg, Karl Schmetzer, and Ulrich Schüssler. Nondestructive analytical methods indicate that the almandine is most likely from India’s Garibpet deposit, giving credence to garnet trade between the eastern coast of India to the Byzantine Empire during the early Middle Ages.
CULTURED PEARLS FROM LAKE KASUMIGAURA: PRODUCTION AND GEMOLOGICAL CHARACTERISTICS

The Chinese freshwater nucleated cultured pearls in this strand from Lake Taihu, also cultured by the Hyriopsis schlegelii × Hyriopsis cumingii hybrid, are 10 mm in diameter and show a color range and luster similar to Kasumiga pearls. Photo by Ahmadjan Abduriyim.
Freshwater pearl culturing began in pre-World War II Japan and reached its peak between 1970 and 1980, only to be overtaken by Chinese production. Current Japanese production at Lake Kasumigaura—Japan’s second-largest lake—is comparatively low, but these cultured pearls have become quite popular in the United States and Europe. Ahmadjan Abduriyim relates the history of Japanese freshwater bead-nucleated pearls, as well as the current state of production and the characteristics of the many-colored specimens.
GEMOLOGICAL CHARACTERIZATION OF SAPPHIRES FROM YOGO GULCH, MONTANA

This suite contains more than 36 carats of Yogo sapphires. Courtesy of RareSource. Photo by Robert Weldon/GIA.
Yogo sapphires are renowned for their clarity and vibrant blue color, and their unique characteristics make them easily recognizable to experienced gemologists. However, mining interests have long found it difficult to maintain long-term activity at this source. In this article, Nathan Renfro, Aaron Palke, and Richard Berg offer a comprehensive look at the history, gemological properties, and trace-element chemistry of the corundum yielded from this important gem deposit in the United States.
SYNTHETIC DIAMONDS CHART

The Summer 2018 G&G contains a foldout wall chart showing the characteristics of synthetic diamonds.
Our newest wall chart, coordinated by Sally Eaton-Magaña and Christopher M. Breeding, presents a visual guide to the growth processes and major gemological spectroscopic features of synthetic diamonds grown by the high-pressure, high-temperature (HPHT) and chemical vapor deposition (CVD) methods. Additional resources for further study are also provided.
LAB NOTES

Diagram showing the proposed model of the beryl and glass assemblage. Final faceting is shown for simplicity. A: The first glass segment (green) is attached to the beryl core (gray). B: Both the core and the first segment are cut to make a flat surface for the second segment. C: The second segment (teal) is attached. D: The segments are again cut. E: The third segment (blue) is attached. F: The assemblage is shown rotated 180° for clarity. All current pieces are cut to create the surface for the final piece. G: The fourth and final segment (purple) is attached. H: Omitted for simplicity, the assembled pavilion would likely be polished flat to make room for the crown. Lastly, the crown (pink) is attached. The diagram was generated using Onshape CAD software.
GIA’s labs report on an emerald imitation created from a beryl and glass assemblage, one natural melee diamond found among a batch of 1,092 HPHT synthetic melee, and a large pinkish orange CVD synthetic diamond.
DIAMONDS FROM THE DEEP

Ringwoodite is the high-pressure form of the mineral olivine (Mg2SiO4) that occurs between 520 and 660 km below the surface of the earth in the transition zone. The first terrestrial observation of this mineral was in a diamond from Juína, Brazil (top left). Water content in this 30 µm inclusion (bottom left) is around 1.4 wt.%, indicating that the global transition zone could contain at least 2.5 times the amount of water as Earth’s oceans. The majority of diamonds come from the cratonic lithosphere (indicated here as yellow diamonds). Superdeep diamonds (indicated here as white and blue diamonds) are rarer and originate from greater depths, often from the transition zone, which extends between 410 and 660 km.
G&G’s newest section highlights the importance of diamond in understanding our planet’s geological formation. This issue’s column focuses on the role diamonds play in understanding the depths at which water is found in the deep earth.
MICRO-WORLD

This copal from Mexico contained a remarkably well-preserved eye-visible mushroom inclusion. Photomicrograph by Nathan Renfro; field of view 9.59 mm.
A mushroom encased in copal, tanzanite with whisker-like merelaniite inclusions, and a star spinel with four and six rays are among the specimens featured in our photomicrography and inclusions section.
GEM NEWS INTERNATIONAL

Left: Three rough garnets (left to right, stones 2, 3, and 4) and one faceted garnet photographed in an LED light source with 6000K color temperature (a daylight-equivalent light simulator). Right: The same stones photographed in an LED light source with 3100K color temperature (an incandescent light simulator). The 2.705 ct faceted stone measures 8.08 × 7.18 × 5.49 mm. Photos by Kevin Schumacher.
Notes from the around the world highlight color-change grossular garnets from Ethiopia, a Mozambican green-blue Maxixe-type beryl, the Gemstones and Sustainable Development Knowledge Hub, and the separation of glass-filled rubies using the DiamondView instrument. Source: GIA @topic:1


Title: Observation of Etched Surface Micro-Features on HPHT Synthetic Diamonds Using Laser Confocal Microscopy Abstract: Figure 1. Laser confocal microscopy (LCM) shows traces of metallic catalyst and step-like growth marks in an HPHT synthetic diamond’s interior. Photo by Xuxu Wu.

China is the world’s largest HPHT synthetic diamond producer, with an annual output of more than 3,000 tons of rough industrial diamonds. The production technology of HPHT synthetic diamond is quite mature, and most Chinese HPHT synthetic diamonds use the hexahedral static pressure method. The diamond crystals grow out of high-purity graphite through a high-temperature and high-pressure process, and then the superfluous graphite is removed by acid cleaning (Z. Song et al., “Identification characteristics of large near-colourless HPHT synthetic diamond from China,” Journal of Gems and Gemmology, Vol. 18, No. 3, 2016, pp. 1–8).
Acid cleaning of HPHT synthetic diamond is usually done with 90% H2SO4 and 10% HNO3. This process can remove graphite and metal impurities that remain on the diamond surface and in crevices (L. Yin et al., “Micromechanism of the artificial diamond’s growth,” Journal of Synthetic Crystals, Vol. 29, No. 4, 2000, pp. 386–387). During the growth process, the metal catalyst and graphite are in close contact with diamond and continuously participate in crystal growth.
To the best of our knowledge, no research has been done on the surface characteristics of HPHT synthetic diamonds after acid cleaning, which can reveal the growth features of HPHT diamond. In this study, 39 HPHT synthetic diamonds produced in China were observed using laser confocal microscopy (LCM). The laser confocal microscopy measures the surface topography of the sample moving focused laser spots over the sample with a galvanometer scanner. The strongest-intensity scanning points in each vertical scan layer are recorded and used to construct the 3D topography through a pixel-by-pixel method (W.-C. Liu et al., “A self-designed laser scanning differential confocal microscopy with a novel vertical scan algorithm for fast image scanning,” IFAC-PapersOnLine, 2017, Vol. 50, No. 1, 2017, pp. 3221–3226). Therefore, the laser confocal microscope can overcome the problem of depth of field and observe the surface characteristics of materials clearly.
The characteristics of the structure after acid cleaning are observed on the surface of an HPHT synthetic diamond and on the inside of the crystal. An HPHT synthetic diamond was cut into thin slices and then washed by acid, exposing its internal structure (figure 1). Metal catalysts and a small amount of graphite remain in diamond crystals during growth, leaving holes in the interior. Due to the lack of raw material for growth in the hole, a step-like structure was left in the space that was not fully filled with crystallized diamond.

Figure 2. 3D scanning of micro-features by LCM shows the depth change and relative spatial relation. Image by Xuxu Wu.
The fine structure of the step-like growth can be expressed by using the 3D scanning function of the laser confocal microscope. The images built in the three-dimensional coordinate system can show the depth and spatial relationship of the microstructures (figure 2). The irregularly etched structures, the depth of voids left by metal catalysts, range from 5 to 17 μm.

Figure 3. Step-like irregular pits and lines on the surface of the HPHT synthetic diamond.
The inset shows a simulation of the sample’s stacked triangular growth structure. Photo
by Xuxu Wu.

Figure 4. The surface of this HPHT synthetic diamond presents several groups of
parallel lines. Photo by Xuxu Wu.
After acid cleaning, HPHT synthetic diamonds will display step-like irregular pits and lines on the surface (figure 3). The triangular growth structures of HPHT synthetic diamonds are stacked on the surface with slight displacement. Rectilinear line marks on the surface of HPHT synthetic diamonds (figure 4) are also very common, and may be traces of the displacements that develop between small crystals due to compression during the growth process.
Characteristic patterns observed on the surface of HPHT synthetic diamonds are related to metal catalysts and diamond particles, revealing the order of growth of synthetic diamonds. The step-like structure with the same angle is very common. The etched microstructure caused by metal catalysts usually displays irregular patterns. The several groups of parallel straight lines could be caused by the displacement and friction between a large number of tiny diamonds in the growth chamber. LCM is very reliable at revealing surface micro-features on HPHT synthetic diamonds, and it should be more widely applied to gemological research.
Contributors’ note: This study was partially supported by the National Natural Science Foundation of China (grants 41473030 and 41272086). Source: GIA @topic:4


Title: Spring 2018 G&G: Color Origin of Green Diamonds, Iridescence in Hematite, and the Outlook from Tucson Abstract: Colored by atomic-level defect arrangments, natural-color green diamonds are among the rarest gemstones found on Earth. The cover photo showcases diamonds that display a range of green hues. The diamonds in the rings (clockwise from top) are a 4.17 ct Fancy Vivid yellowish green, a 10.18 ct Fancy Intense yellow-green, and a 3.88 ct Fancy Vivid green, respectively. The unmounted diamonds in the top row are a 1.42 ct Fancy Vivid bluish green, a 1.01 ct Fancy Vivid yellowish green, and a 2.06 ct Fancy Vivid green-blue. In the bottom row are a 0.55 ct Fancy Vivid green and a 0.55 ct Fancy Vivid bluish green. Photo by Robert Weldon/GIA, courtesy of Optimum Diamonds.

Green is among the rarest hues found in colored diamonds, and there have been few published studies. The lead article of the Spring 2018 Gems & Gemology reviews the characteristics of these uncommon gems as observed at GIA’s labs. Other articles explore the causes of iridescence in Brazilian hematite and the application of DNA techniques to identifying Japanese akoya cultured pearls. The issue also includes coverage of the annual Tucson gem shows, the 2018 Challenge, and the results of the Dr. Edward J. Gübelin Most Valuable Article Award.
NATURAL-COLOR GREEN DIAMONDS: A BEAUTIFUL CONUNDRUM

Natural-color green diamonds such as these beautiful gems span a range of colors. From left to right: Fancy Vivid green-blue (2.06 ct), Fancy Vivid yellow-green (1.01 ct), Fancy Dark gray greenish yellow (3.08 ct), and Fancy Intense yellow-green (2.01 ct). Each of the four main color-causing mechanisms usually produces slightly different green hues. Photo by Robert Weldon/GIA, courtesy of Optimum Diamonds.
Diamonds with natural color comprise less than 0.4% of all diamonds submitted to GIA. Of these, stones with a pure green hue are among the rarest. In the last decade, GIA labs have examined more than 50,000 natural-color green diamonds. The lead article, by Christopher M. Breeding, Sally Eaton-Magaña, and James E. Shigley, documents their properties and discusses the radiation exposure and atomic-level defects that cause this hue in diamonds, as well as the difficulties of separating natural-color and treated material.
IRIDESCENCE IN METAMORPHIC “RAINBOW” HEMATITE

Rainbow hematite from the Andrade mine in João Monlevade, Minas Gerais, Brazil. Photo © Rock Currier, Mindat.org.
Rainbow hematite was first uncovered from Minas Gerais, Brazil, and since then it has been used in award-winning jewelry pieces. Xiayang Lin and her coauthors investigate the cause of iridescence in this material through electron microscopy, atomic force microscopy, and synchrotron X-ray diffraction analysis. They assert that the iridescence arises from a periodic microstructure, consisting of spindle-shaped hematite nanocrystals containing minor Al and P impurities, resulting from arrested crystal growth.
DNA TECHNIQUES APPLIED TO THE IDENTIFICATION OF JAPANESE PINCTADA FUCATA PEARLS

Between November and January of each year, pearls are harvested at Uwajima from akoya shells operated on either six months prior (classified by the Japanese as tonen-mono) or 18 months prior (koshi-mono). A: An Uwajima pearl farmer’s work hut. B–F: Various scenes from harvesting in a shed on one of the floating rafts. B: Oysters are removed from a net on the floor to separate the living mollusks from the dead ones. C: After the shells are opened on a table, the adductor muscles are removed and the other soft tissues are separated. D: The liquefied soft tissues containing the bead-cultured pearls are collected in a blue plastic bucket. E: The remaining organic matter containing smaller “keshi” pearls is poured into a separator to remove the keshi pearls. F: The bead-cultured pearls are placed into a wooden box for cleaning and subsequent inspection. Photos by K. Saruwatari.
One of the challenges of modern pearl identification is the separation of saltwater mollusk species that produce white, cream, or silver nacreous pearls. A team led by Kazuko Saruwatari used DNA techniques on akoya pearl-producing mollusks from Uwajima, Ehime Prefecture, Japan, to see if the mollusk species could be pinpointed. The authors were able to amplify the 16S rRNA gene from the mantle tissues of donor and host pearl oysters as well as from tiny amounts of pearl powder, and successfully identified the Pinctada fucata species.
LAB NOTES

A face-up view of the near-colorless 1.21 ct fracture-filled square modified brilliant cut. Photo by Robison McMurtry.
In this issue, reports from GIA’s labs include an HPHT-processed diamond fraudulently represented as untreated, the analysis of five CVD synthetic diamonds greater than three carats, and a natural blister resulting from the entombment of a pearlfish within a P. maxima shell.
MICRO-WORLD

Prominent agate-like banding was seen in the opal. Photomicrograph by Nathan Renfro; field of view 8.22 mm.
Entries in G&G’s section on inclusions and photomicrography spotlight an opal with agate-like banding, a natural diamond with etch channels, and a pink tourmaline crystal within a spodumene host
GEM NEWS INTERNATIONAL

Although traffic at the AGTA show was lighter than in some previous years, demand was brisk and most traders were satisfied with their 2018 business. Photo by Kevin Schumacher.
In addition to our annual Tucson report, GNI features entries on aquamarine from Pakistan’s Shigar Valley, Concho pearls from Texas, and an irradiated and annealed blue type Ia diamond.

The Spring issue also contains the 2018 Gems & Gemology Challenge quiz. Score 75% or better and you’ll receive a certificate of completion (PDF file); earn a perfect score and your name will be listed in the Fall 2018 issue. Mail-in cards and online entries for the Challenge must be submitted by Friday, August 10, 2018. Source: GIA @topic:1


Title: Retail Group Sees Good Holiday; Fancy Color Diamonds Cap Auction Season Abstract: The 14.93 ct “Pink Promise” Fancy Vivid pink diamond may be the most expensive stone Christie’s has ever sold at its Hong Kong auction house. The diamond is expected to sell for as much as $40 million. Photo courtesy of Christie's Images.

The U.S. National Retail Federation predicts that overall holiday spending will increase 3.6% to 4% over last year, citing a strong economy and rising confidence in employment and wages.

The trade group noted that retailers have been stocking record amounts of merchandise in preparation for a good season.

As reported last month, jewelry sales in the U.S. have been running 5.6% above last year’s levels. Demand for diamonds and gemstones, however, remains concentrated in relatively narrow categories of goods. In addition, according to press reports, consumers seem to be edging from tangibles, such as jewelry, toward travel and other experience-related products. This means competition for their discretionary dollars will be keener than ever.

Retail sales in China continue to recover with most of the major retailers reporting double-digit gains over last year’s totals. Demand for gem-set jewelry declined slightly on the mainland, but grew sharply in Hong Kong and Macau.
AUCTIONS
The sale of a 24.78 ct Fancy Intense pink diamond made news around the world seven years ago for its astounding price: $46.2 million. The diamond, named the Graff Pink by its buyer, brought the highest price ever paid for a gemstone at auction.

A similarly striking diamond (both were graded by GIA) was the centerpiece of Sotheby’s Geneva Magnificent Jewels auction on Nov. 15. It is 12.5 carats larger than the Graff Pink, but carried a pre-sale estimate of $20 to $30 million.

While the final price could go higher, the pre-sale estimate price reflects a key factor in auction prices at those extreme levels: the pool of potential buyers in the market for such a stone is quite small. If one or two major buyers are out of the market for some reason, prices for these stones can fall well short of similar items in previous sales, even as demand and prices for less costly gems remain solid.

It is true that auction prices for major diamonds and colored gems are not setting records at the pace they had several years ago, but in general they have remained solid.

The other major diamonds on the block at the Sotheby’s Nov. 15 sale were a pair of Fancy Intense yellows called the Donnersmarck Diamonds, named for La Paiva the Countess Henckel von Donnersmarck. The countess began a relationship with Prussian industrialist Guido Henckel von Donnersmarck in the early 1850s and married him in 1871. The two GIA-graded diamonds are 102.54 ct and 82.48 ct which, when last sold in 2007, brought in $3.25 million and $4.66 million respectively – with the smaller stone unexpectedly realizing the higher price.

A pink diamond that Christie’s calls “the most expensive jewel ever offered” at its Hong Kong house is expected to bring as much as $40 million on Nov. 17. The 14.93 ct “Pink Promise” diamond is a GIA-graded Fancy Vivid pink oval cut diamond mounted into a ring.

The same sale will also feature an 8.8 ct Fancy Intense pink diamond expected to sell for $8 to $12 million and an 8.17 ct Burmese ruby ring that is estimated to sell at $5.8 to $8 million. Source: GIA @topic:8


Title: Spring 2017 G&G: Brazil’s Diamond Production, Cuprian Liddicoatite, Silicon in Corundum, and Tucson Coverage Abstract: The lead article of this issue covers Brazilian diamond production, which reached its peak in the late 1700s. Our cover shows a brooch dating back to the mid-19th century. This piece contains a 0.77 ct natural Fancy Light pink antique pear-shaped diamond set in darkly patinated silver ribbons over gold. The total weight of the diamonds exceeds 5.20 carats. Photo by Robert Weldon/GIA, courtesy of Lang Antique & Estate Jewelry.

	From Brazilian diamonds and Japanese jadeite to Indian iridescent quartz and Polish by-product zincite, a world of wide-ranging topics is covered in the Spring 2017 issue of Gems & Gemology. The issue looks at historical and unexpected sources of gemstones, plus surprising discoveries revealed through advanced chemical analyses. News and updates from the annual Tucson gem shows and our multiple-choice Challenge quiz are also included in the Spring issue.

	BRAZILIAN DIAMONDS: A HISTORICAL AND RECENT PERSPECTIVE

	The Portuguese Placa dos Três Militares, or Badge of the Three Military Orders, was
	made in 1789, and is now part of the crown jewelry collection of the Ajuda National
	Palace in Lisbon. The badge consists of Brazilian diamonds as well as emeralds and
	rubies, and it is designed in a way to conceal the metal mounting and emphasize the
	gems. Photo by Manuel Silveira Ramos, courtesy of the Ajuda National Palace.

	Brazil is known for its wealth of colored stones, but it was at one time the world’s leading diamond producer. For three centuries Brazil has supplied a steady, if relatively small, supply of diamonds to the world market. It is also a source of superdeep and fancy-color diamonds and carbonado. In Brazil, diamonds are gathered from alluvial deposits (primarily in Mato Grosso and Minas Gerais), while primary sources remain unknown. Authors Darcy Svisero, James Shigley, and Robert Weldon look at Brazil’s centuries-old diamond production with historical perspective, geological insight, and expectations for future mining.

	COPPER-BEARING LIDDICOATITE TOURMALINE

	Six of the 13 cuprian liddicoatite tourmalines from this study. The faceted stones weigh 1.59–9.63 ct (average 3.95 ct). They are transparent and have greenish blue, green-blue, and green colors. Photos by Masumi Saito.

	Copper-bearing (Paraíba) tourmaline is usually classified as part of the elbaite species. Recently, 13 cuprian tourmalines submitted to GIA’s Tokyo lab were analyzed with LA-ICP-MS for origin determination. While the origin of the stones remains unknown, Yusuke Katsurada and Ziyin Sun discuss the surprising results that led them to classify the samples as liddicoatite, rather than elbaite.

	THE ROLE OF SILICON IN THE COLOR OF GEM CORUNDUM

	Paula Crevoshay’s “Yogo Columbine” pendant displays the remarkably consistent blue color of Yogo sapphires: 243 in all, with a total weight of 13.89 carats. The piece also contains 0.59 ct of yellow sapphires and 1.37 ct of diamonds, set in 18K yellow and white gold. Photo by Orasa Weldon.

	The chemical interactions of silicon, titanium, and magnesium are known to influence the color of gem-quality corundum, but until recently the role of silicon has not been fully understood. John Emmett, Jennifer Stone-Sundberg, Yunbin Guan, and Ziyin Sun explore how ion implant standards and the application of SIMS has led to accurate measurement of silicon in corundum for the first time. This measurement makes clear the important role of silicon in corundum color; the blue of Yogo sapphire from Montana is used to illustrate this discovery.

	JAPANESE JADEITE: HISTORY, CHARACTERISTICS, AND COMPARISON WITH OTHER SOURCES

	A large, attractive jadeite boulder from Itoigawa, Japan, characterized by mixed white
	and green colors. This boulder weighs 40.5 kg and measures approximately 39 cm
	high, 32 cm long, and 26 cm wide. Photo by Ahmadjan Abduriyim.

	Gem-quality jadeite jade has been known from Japan for millennia. In this article, Ahmadjan Abduriyim, Kazuko Saruwatari, and Yusuke Katsurada examine the historical context, chemical composition, and color of Japanese jadeite. They also compare characteristics of samples from the Itoigawa, Omi, and Wakasa regions to jadeite from Burmese, Guatemalan, and Russian deposits.

	CAUSES OF IRIDESCENCE IN NATURAL QUARTZ

	Iridescence is clearly visible on the minor z face of this iris quartz from Jalgaon, India.
	Photomicrograph by Peter J. Heaney; field of view 4.5 mm.

	The phenomenon of iridescence in gemstones is caused by either thin films or repetitive substructures. In an exploration of iris quartz specimens from Jalgaon District, India, Xiayang Lin and Peter Heaney discover a ridge and valley structure, produced by differential etching on the material’s minor z face, which produces its iridescent effect.

	CHARACTERISTICS OF GEM-QUALITY BY-PRODUCT SYNTHETIC ZINCITE

	Most of the by-product synthetic zincites in this study had a reddish orange to yellow color; one sample (ZnO-G) was yellowish green. Top row, left to right: samples ZnO-LC (69.23 ct) and ZnO-SC (31.71 ct). Bottom row, left to right: samples ZnO-G (0.32 ct) and zin-7 (5.61 ct). Composite photo by Ji Zhang.

	Synthetic zincite has been found in industrial kilns in Poland as a by-product of zinc oxide powder production. This accidental zincite has better transparency and brighter color than its natural counterpart. Ji Zhang, Yujie Gao, and Guanghai Shi examine samples of by-product synthetic zincite from a Polish foundry to establish their distinguishing characteristics, identify their inclusions, and find their cause of color.

	LAB NOTES

	This 0.42 ct green HPHT synthetic diamond displayed strong growth sectors that were observed without magnification. Photo by Jian Xin (Jae) Liao.

	GIA’s gemologists report on notable lab submissions, including a surprising source of green color in HPHT synthetic diamond, a Paraíba tourmaline with an unusual submetallic coating, and a cape diamond showing yellow phosphorescence.

	MICRO-WORLD

	In this scene, pyrite inclusions have dissolved, leaving behind hematite and goethite, both of which react dramatically to polarized light. Photomicrograph by John Koivula; field of view 10 mm.

	The inner world of gemstones continues to captivate, and the Spring 2017 section features sapphires showing negative crystals, flame-like structures in precious opal from Ethiopia, and a mysterious inclusion combination in Sri Lankan topaz.

	GEM NEWS INTERNATIONAL

	A 28.21 ct freeform Oregon sunstone from the Dust Devil mine is the centerpiece of this ring. Photo courtesy of Sonja Kreis Unique Jewelry.

	The GNI section contains G&G’s annual coverage of the Tucson gem shows. Highlights include emeralds from a new deposit in Ethiopia and a Burmese gem update following the lifting of U.S. sanctions on Myanmar. Other entries report on the chemical composition of color-change pyrope-spessartine garnet, and a calcite sphere exhibiting strong phosphorescence.

	The Spring issue also contains the 2017 Gems & Gemology Challenge. Score 75% or better and you’ll receive a certificate of completion (PDF file); earn a perfect score and your name will be listed in the Fall 2017 issue. Mail-in cards and online entries for the Challenge must be submitted by Friday, August 11, 2017. Source: GIA @topic:1


Title: Fall 2016 G&G: CVD Synthetic Diamonds Survey, Reversible Color Change in Blue Zircon Abstract: Nathan Renfro’s article in this issue describes how exposing blue zircon to long-wave UV radiation causes them to turn brown, and how this color modification can be reversed. The 7.95 ct blue zircon ring on the cover is set in 18K white gold and surrounded by 2.43 carats of rubies. It is shown alongside a similar ring with a 5.46 ct tanzanite center stone. Both were designed by Loretta Castoro of Los Angeles for her KissMe collection. Photo by Kevin Schumacher, courtesy of Loretta Castoro.

	CVD-grown diamonds, colored stones, and Indonesian cultured pearls are featured in the latest Gems & Gemology. The Fall 2016 issue reviews the characteristics of several hundred CVD synthetic diamonds; describes how long-wave UV radiation can turn blue zircon brown; and examines the properties of Vietnamese peridot, grandidierite from Madagascar, and Russian alluvial sapphire. The issue also includes a field report from a trip to a cultured pearl farm on the Indonesian island of Lombok.

	OBSERVATIONS ON CVD-GROWN SYNTHETIC DIAMONDS: A REVIEW

	Since 2003, GIA has examined hundreds of gem-quality CVD synthetic diamonds. As growth technology becomes more advanced, the size and quality of these synthetics continue to increase. In the lead article, Sally Eaton-Magaña and James Shigley survey several hundred, CVD samples, interpreting grading factors and analytical data to gain greater insight into indicators of CVD origin.

The lead article of the Fall 2016 issue reviews the characteristics reported from several hundred CVD synthetic diamonds examined by GIA over the past 13 years. These near-colorless and Fancy Vivid purplish pink samples are representative of most of the CVD-grown samples seen at GIA labs. Photo by Robert Weldon/GIA.

	REVERSIBLE COLOR MODIFICATION OF BLUE ZIRCON BY LONG-WAVE ULTRAVIOLET RADIATION

	After learning from gem dealers that blue zircons had turned brown after exposure to long-wave UV radiation, Nathan Renfro undertook a study to see if the blue color could be restored by exposure to incandescent light. Spectroscopic analyses pinpointed the features responsible for the color modification.

	The 11 faceted blue zircons of unknown origin seen on the left all showed a brown face-up color after several minutes of long-wave UV exposure. Photo by C.D. Mengason.

	SAPPHIRES FROM THE SUTARA PLACER IN THE RUSSIAN FAR EAST

	With only one placer deposit of gem-quality sapphire, Russia has long relied on sapphire from other parts of the world. But the Sutara River region of Russia’s Jewish Autonomous District is another potential source of corundum. A team of researchers led by Svetlana Buravleva uncovered sapphire at the deposit and studied the chemical composition and gemological properties of the cabochon-grade material.

	This silver pendant contains a 65.5 ct sapphire cabochon from Sutara, in the Russian
	Far East. Photo by Svetlana Buravleva, courtesy of A. Kurnosov.

	A NEW DEPOSIT OF GEM-QUALITY GRANDIDIERITE IN MADAGASCAR

	A deposit of grandidierite outside Tranomaro, Madagascar, has yielded bluish green to greenish blue crystals that are among the purest known examples of this material. Delphine Bruyère and her coauthors examined samples from the new source, recording its gemological properties, collecting chemical composition data, and discussing the material’s market potential.

This 0.11 ct round brilliant grandidierite from Madagascar has no eye-visible flaws. Photo by Delphine Bruyere.

	PERIDOT FROM THE CENTRAL HIGHLANDS OF VIETNAM

	Recognizing the importance of Vietnamese peridot to the global gem industry, Nguyen Thi Minh Thuyet and colleagues established the geological and P-T formation of the material, concluding that it derives from a spinel lherzolite source. They also compared the gemological characteristics and geochemical data of peridot from the Central Highlands to specimens from other known localities.

The light yellowish green 5.09 ct peridot in this gold ring is from Vietnam’s Bien Ho deposit. Photo by Nguyen Thi Minh Thuyet.

	BEAD-CULTURED AND NON-BEAD-CULTURED PEARLS FROM LOMBOK, INDONESIA

	In this field report, Nicholas Sturman and his coauthors recount their visit to a pearl hatchery in Lombok, Indonesia. There they observed the daily activities of a pearl farm and collected bead-cultured and non-bead-cultured pearls from P. maxima mollusks for further study and future identification purposes.

A group of bead-cultured pearls of various hues recovered from hatchery-bred Pinctada maxima oysters at Lombok, Indonesia. Photo by Julie Poli.

	LAB NOTES

	Highlights from the Fall Lab Notes section include reports on the capabilities of GIA’s melee sorting service, a sapphire rough filled with green lead glass, a treated pink diamond colored by red luminescence, and a purple fluorite inclusion in emerald.

	MICRO-WORLD

G&G’s photomicrography section includes entries on unusual growth zoning in Pakistani aquamarine, etch features in spinel from Madagascar, and a mobile fluorite inclusion within quartz.

	GEM NEWS INTERNATIONAL

	The Fall 2016 GNI section provides updates on Tanzanian colored gemstone deposits, “Punsiri”-type spectral features in natural yellow sapphire, and use of the DiamondView instrument to identify impregnated jadeite. Source: GIA @topic:4


Title: Fluid CH4 and H2 Trapped Around Metallic Inclusions in HPHT Synthetic Diamond Abstract: This article was published in Diamond and Related Materials, Volume 68, 2016, Pages 10–12.

	Abstract
Diamonds grown by the high-pressure, high-temperature (HPHT) method commonly contain solid inclusions from the metallic solvent-catalyst they are grown in. Such inclusions give rise to their familiar magnetism. Upon recent analysis of 4 commercial HPHT synthetic diamonds from different sources, several of these solid inclusions were found to have a thin, fluid film or jacket of methane (CH4) and hydrogen (H2) trapped at the interface between the solid inclusion and surrounding diamond. Raman spectroscopy reveals peaks near 2918 cm− 1 and 4156 cm− 1 that correspond to the main vibrations of CH4 and H2, respectively. In some cases the peak position is shifted down by a few wavenumbers due to elevated pressure within the inclusions.

The CH4 and H2 probably formed as the inclusion cooled, when dissolved hydrogen atoms were no longer soluble in the solidifying inclusion phases and were forced to exsolve as H2, as well as CH4 by combining with available carbon. Inclusions can provide an indirect means of studying the effective growth environment. These findings show that hydrogen is commonly present at the site of diamond growth in HPHT synthesis, even if it is not intentionally added among the starting materials. Hydrogen is known to influence diamond growth, based on doping experiments, suggesting that there could be unrealized benefits to gaining better control over hydrogen during routine HPHT diamond synthesis.

Purchase the full article. Source: GIA @topic:4


Title: Summer 2016 G&G: Diamonds from Diavik, Responsible Sourcing, and Fabergé Cossack Figures Abstract: The lead article in this issue examines the discovery and geology of the Diavik diamond mine, as well as the nature
of the operations at this remote site in Canada’s Northwest Territories, just 220 km south of the Arctic Circle.
The aerial photo on the cover, taken in the summer of 2014, captures Diavik’s isolation and the extent of its operations.
Photo by Dave Brosha, courtesy of Diavik Diamond Mine.

	Diamonds and colored stones, carving and mining, historical treasures and the future of the industry are all featured in the latest Gems & Gemology. The Summer 2016 issue leads with the Diavik diamond mine in Canada’s Northwest Territories. Other articles examine Fabergé figures depicting Russian imperial bodyguards, efforts to bring a sustainable and ethical supply chain to the colored stone industry, the carving of a large opal rough into a museum-quality piece, and the bygone adventures of mine engineer Peter Rainier at the Colombian emerald mecca of Chivor.

	MINING DIAMONDS IN THE CANADIAN ARCTIC: THE DIAVIK MINE

The 187.7 ct “Diavik Foxfire,” discovered in spring 2015, is the largest gem-quality rough diamond found to date at the mine. Photo courtesy of Rio Tinto Diamonds.

	Canada’s remote Diavik mine is one of the world’s preeminent sources of gem diamonds, producing over 100 million carats since 2003. In the lead article, Dr. James Shigley and his team review the discovery, development, and operation of the mine, which is expected to produce through 2024, when the land will be restored through reclamation and remediation efforts. The article is accompanied by exclusive videos captured at Diavik.

	FABERGÉ COSSACK FIGURES CREATED FROM RUSSIAN GEMSTONES

	The Fabergé hardstone figure of Chamber Cossacks A.A. Kudinov, who guarded
	Empress Maria Feodorovna from 1878 to 1915. Photo courtesy of Pavlovsk State Museum
	and Gafifullin (2014).

	Between 1908 and 1916, the Fabergé workshops created approximately 50 hardstone figures representing the Russian people, using Russian gems and precious metals. Timothy Adams and Christel Ludewig McCanless examine two hardstone figures, commissioned by Nicholas II, of Cossack bodyguards who served the Romanov empresses.

	THE COLOR OF RESPONSIBILITY: ETHICAL ISSUES AND SOLUTIONS IN COLORED GEMSTONES

	The mining and processing of colored stones, a multibillion-dollar industry, still lacks an ethical and sustainable mine-to-market supply chain. Jennifer-Lynn Archuleta reports on the inherent challenges and the ongoing efforts  to bring traceability, transparency, and sustainability to the world of colored stones.

	THE CHALLENGES OF CUTTING A LARGE GEM OPAL ROUGH

A side view of the Australian opal rough shows all the color bars and intervening layers of colorless potch. Photo by Robert Weldon/GIA.

	Theodore Grussing explains how he planned and cut a 3,019 ct piece of Australian white opal rough into the Molly Stone, a 1,040 ct museum quality piece with play-of-color across the entire surface. This article describes the many considerations involved in creating this one-of-a-kind gem. Video showing the creation of the Molly Stone enhances the reader’s understanding of the cutting process.

	IN RAINIER’S FOOTSTEPS: JOURNEY TO THE CHIVOR EMERALD MINE

 Colombia’s Sinaí Valley, the sandstone monolith of El Pulpito hangs from a steep cliff in the top right. The Chivor mine is just out of view above the rock. Photo by Robert Weldon/GIA.

	Robert Weldon and coauthors take readers on a trek through Colombian history as they journey to the world-famous Chivor mine, guided by the memoirs of Peter W. Rainier. The field report is accompanied by historical photos from the mine and video of the authors’ journey.

	LAB NOTES

	The Lab Notes section reports on a unique drilled emerald, a natural spinel with an unusual yellowish green color, and the largest blue HPHT synthetic diamonds to date.

	MICRO-WORLD

G&G’s photomicrography section features a metal sulfide inclusion in a pink pyrope garnet, a topaz hosting a triplite inclusion, and a stunning aurora effect in an iris agate (with accompanying video).

	GEM NEWS INTERNATIONAL

Submitted as synthetic diamonds, the 0.99 ct blue-green emerald step cut (left), 0.85 ct brown-yellow standard round brilliant (center), and 1.90 ct deep green standard round brilliant (right) were all identified as synthetic moissanite. Photo by Yanjun Song.

	Highlights from the GNI section include Chinese amber treated through steam dyeing, the spectral characteristics of P. mazatlanica and P. margaritifera oyster species, synthetic moissanite imitating synthetic colored diamond, and more entries from the Tucson gem shows.

	2016 G&G CHALLENGE

	For those interested in testing their knowledge of our 2015 content, the 2016 G&G Challenge will be open until Friday, August 12. Participants who score 75% or higher will receive a certificate of completion, while respondents who earn a perfect score will be listed in the Fall 2016 issue of Gems & Gemology. Source: GIA @topic:7


Title: The Impact of Internal Whitish And Reflective Graining on the Clarity Grading of D-To-Z Color Diamonds at the GIA Laboratory Abstract: Unlike many other characteristics that affect the clarity grade of a diamond, determination of the impact of “whitish” graining and “reflective” graining requires analysis that goes beyond visibility at 10× magnification. The importance of this determination is further underscored by the fact that such graining often is the only characteristic present in large, high-clarity, high-color diamonds. This article reviews the history of reporting on such graining by the GIA Laboratory, considers the causes of the different types of graining most commonly encountered, and examines the methodology and critical assessment GIA graders use to determine the impact of such graining on the clarity grade of a diamond. Source: GIA @topic:4


Title: A New Defect Center in Type Ib Diamond Inducing One Phonon Infrared Absorption: The Y Center Abstract: This paper describes the discovery of a new defect center in natural and synthetic type Ib diamonds: the Y center. Sixty-eight natural and synthetic diamonds with detectable C centers, ranging from 0.01 to 1.34 ct and representing common colors for type Ib diamonds (various hues of yellow, orange, brown, and “olive”) were studied.

The other color centers traditionally responsible for one-phonon absorption (i.e., spectral absorption due to the presence of certain defects in the diamond’s lattice structure) include single isolated boron, the A center (di-nitrogen), the B center (four nitrogen atoms surrounding an atomic vacancy in the diamond lattice), the C center (single-substitutional nitrogen, N0), the X center (positively charged single-substitutional nitrogen, N+), and the D, E, and F centers, which have not been attributed to any specific defect.

After correction and normalization of the samples’ infrared spectra, and an attempt to determine the A, B, and C center nitrogen content using spectral fitting data, the researchers found that the margin of error for the C center content was at least 50%. This suggests that some absorption bands underlie the well-known single-substitutional nitrogen absorption at 1130 cm–1. For this reason, all spectra are decomposed again by progressive subtraction of the A, B, C, and X center absorptions. For 38 diamonds, this resulted in a consistent residual absorption with a relatively broad apparent maximum centered at ~1145 cm–1.

A large sample of type Ib diamonds confirmed that this new absorption system is not an artifact of the original spectral decomposition work. The authors propose to call it the Y center because it is clearly related to the single-substitutional nitrogen system of the last named one-phonon infrared absorption center, the X center.

Abstracted by Edward R. Blomgren Source: GIA @topic:4


Title: Aviat Diamonds: A Window into the Deep Lithospheric Mantle Beneath the Northern Churchill Province, Melville Peninsula, Canada Abstract: The Aviat kimberlites are located in Melville Peninsula in northeastern Nunavut. They are part of the Rae craton, which is composed of Archean granitoid rocks, supracrustal belts, and Paleoproterozoic metasedimentray rocks. The carbon isotopic composition, nitrogen concentration, and nitrogen aggregation state of 70 samples from these kimberlites were analyzed to help understand the composition of diamond-forming fluids, paragenesis of diamond source, mantle residence history, and thermal history of the subcratonic lithospheric mantle. The colors of samples were colorless, gray, brown, and green.

FTIR analysis revealed that the majority were type IaAB, including IaA and IaB. Total nitrogen content ranged from 13 to 1467 ppma. The Aviat diamonds were relatively rich in hydrogen. Absorption bands at 3107, 2786, and 1404 cm–1, caused by bending and stretching of the vinylidene group (C=CH2), were observed in most samples. An additional hydrogen-related band at 3237 cm–1 was also detected.

SIMS analysis revealed nitrogen content ranging from 1 to 1724 ppma. The δ13C isotopic analysis suggested that these diamonds were precipitated mainly from carbonate-bearing fluids. Large variations in nitrogen content and δ13C values, though they were not correlated, were observed in growth sectors, suggesting multiple events of fluid derivation from different sources, mainly ecologitic and also probably peridotitic. But the relationship between CL and carbon isotopic composition suggested that non-luminescent diamond may have been formed during one episode of growth. The Aviat diamonds were possibly formed from diamond-forming fluids or melts from several orogenic events, such as transportation of graphitized organic matter and marine carbonates into the deep mantle via subducting oceanic slabs.

Catastrophic platelet degradation was suggested by the positive correlation between platelets and B aggregates of nitrogen. This phenomenon was probably caused by transient heating events or deformation or both during mantle residence. Blue luminescence of nitrogen-rich samples may be related to intense degradation of platelets. The residence temperature of most samples was extrapolated to ~1050–1150°C, suggestive of a diamond source near the top of diamond stability field at ~150–170 km.

Abstracted by Kyaw Soe Moe Source: GIA @topic:1


Title: The Use of Laser and X-Ray Scanning to Create a Model of the Historic Koh-I-Noor Diamond Abstract: For centuries, the Koh-i-Noor was one of the world’s largest diamonds. It was recut in 1852 from its historic form of 186.1 old carats to an oval of 105.60 modern carats. While the modern shape is well documented, the original form is not. Fortunately, the Natural History Museum in London commissioned a mold of the diamond in 1851 before it was recut. Using one of two plaster replicas made from this mold, the present study captured the surface topology of the original Koh-i-Noor through photography plus laser and X-ray scanning methods. A crystallographic analysis of the major facets determined the diamond’s orientation within a “perfect” diamond crystal, which was used to refute one theory about the diamond’s genealogy. Computer modeling established the orientation of the recut diamond within the historic version. Information from this study was used to create an accurate replica from cubic zirconia. Source: GIA @topic:4


Title: Color Alterations in CVD Synthetic Diamond with Heat and UV Exposure: Implications for Color Grading and Identification Abstract: In response to heat and UV exposure, some synthetic diamond gemstones grown by chemical vapor deposition exhibit large, reversible changes in color. A significant reduction in color was achieved by heating several CVD synthetic gemstones to 450°C. Conversely, a darker color was observed in samples following exposure to UV radiation (such as that used in gem testing). Both the heated and UV-exposed samples returned to their initial (stable) color when they were illuminated for >30 minutes with a standard daylight-equivalent lamp used for grading. However, these color states did not change with time when the samples were kept in the dark. Heating and UV exposure also influenced the strengths of various IR absorption features that might be used to identify such a sample as a CVD synthetic. These nonpermanent changes might affect the apparent color grade of a CVD synthetic diamond, and care must be employed in the interpretation of spectroscopic features used to determine a stone’s natural or synthetic origin. Source: GIA @topic:4


Title: Aviat Diamonds: A Window into the Deep Lithospheric Mantle Beneath the Northern Churchill Province, Melville Peninsula, Canada Abstract: The Aviat kimberlites are located in Melville Peninsula in northeastern Nunavut. They are part of the Rae craton, which is composed of Archean granitoid rocks, supracrustal belts and Paleoproterozoic metasedimentray rocks. Carbon isotopic composition, nitrogen concentration, and nitrogen aggregation state of 70 samples from these kimberlites were analyzed to help understanding composition of diamond-forming fluids, paragenesis of diamond source, mantle residence history, and thermal history of the subcratonic lithospheric mantle. The colors of samples were colorless, gray, brown and green.

The FTIR analysis revealed that majority of these samples were type IaAB, including IaA and IaB. Total nitrogen content ranged from 13 to 1467 ppma. The Aviat diamonds were relatively rich in hydrogen. The absorption bands at 3107, 2786, and 1404 cm–1, caused by bending and stretching of the vinylidene group (C=CH2), were observed in most samples. Additional hydrogen-related band at 3237 cm–1 was also detected.

SIMS revealed nitrogen content ranged from 1 to 1724 ppma. The δ13C isotopic analysis suggested that these diamonds were precipitated mainly from carbonate-bearing fluids. Large variations in nitrogen content and δ13C values, although they were not correlated, were observed in growth sectors, suggesting multiple events of fluid derivation from different sources, mainly ecologitic, and also probably peridotitic. However, the relationship between CL and carbon isotopic composition suggested that non-luminescent diamond may have been formed during one episode of growth. The Aviat diamonds were possibly formed from diamond forming fluids or melts from several orogenic events, such as transportation of graphitized organic matters and marine carbonates into deep mantle via subducting oceanic slabs.

The catastrophic platelet degradation was suggested by the positive correlation between platelets and B aggregates of nitrogen. This phenomenon was probably caused by transient heating events or deformation or both during mantle residence. Blue luminescence of nitrogen-rich samples may be related to intense degradation of platelets. The residence temperature of most samples was extrapolated to ~1050–1150°C, suggestive of diamond source near the top of diamond stability field at ~150–170 km.

Abstracted by Kyaw Soe Moe Source: GIA @topic:1


Title: Growth Strategy for Controlling Dislocation Densities and Crystal Morphologies of Single Crystal Diamond by Using Pyramidal-Shape Substrates Abstract: A single synthetic diamond crystal can be used as an electronic device because of its properties, such as a high breakdown field and thermal conductivity. However, defects, such as dislocation bundles, which were formed during growth process, can cause current leakage, higher bandgap, and birefringence. Defect-free single diamond crystal that is large enough to be used as an electronic device is difficult to grow using current methods. For example, the “threading dislocations” can be formed in a CVD diamond using (001)-oriented substrate. The authors demonstrated that these defects could be reduced by modifying substrate’s shape and orientations.

									Two type Ib HPHT-grown, pyramidal substrates, type A and type B, were used to grow single CVD crystals in this research. The {100} directions in type A substrate and {110} directions in type B were polished into inclined faces with 20°, 30°, and 40° angles. Both possessed a square top measuring 200 x 200 µm2. Crystals were grown on these substrates using plasma-assisted CVD technique with power density of 100 W/cm3 and methane concentration of 5% at 850°C, achieving a growth rate of 13 microns per hour.

									After removal of the substrate, the fully grown CVD crystals showed high transparency. Nitrogen-related defects were not detected. The inclined faces in type A substrate helped prevent twin sectors from reaching the top face. The growth rates of the lateral and top faces were 32.5 and 13.5 µm per hour, respectively. When thickness reached about 490 microns, the inclined faces started to disappear. The dislocations, originating from the square top of a pyramidal substrate, were observed in a crystal grown on type A substrate with 20° dislocations. However, these dislocations were diverted toward the edges rather than the top. Photoluminescence image showed that the inclined faces effectively diverted the direction of threading dislocations from {100} to {110} direction. Absence of sharp edges in these pyramidal substrates also helped in reducing dislocations. The lateral surfaces had the highest growth rate and possessed “fish scale” morphology in type A grown crystals, a morphology not observed in type B crystals. A maximum thickness of 2.2 mm could be achieved with a dislocation of 40° on type B substrate. A crystal 1.70 mm thick containing very low defects was achieved using type B substrate with 20° or 30° dislocations.

Abstracted by Kyaw Soe Moe Source: GIA @topic:4


Title: Gemstone Portrait Artist Angie Crabtree Abstract: Figure 1. This selection of Angie Crabtree’s paintings displayed at the AGTA GemFair showcases opal and cut diamond. Photo by GIA.
The 2019 AGTA show in Tucson featured the work of a gemstone portrait artist. On display in Angie Crabtree’s booth were her oil paintings (figure 1) on canvas and panel. She also had a table with paints, palettes, and other supplies so people could see her at work (figure 2).
Crabtree’s portraits range in size up to 64 × 48 inches. She said people are excited to see gemstones in great size and detail. One painting can take more than 300 hours to complete. She said because people outside the gem and jewelry industry don’t always recognize the subjects as gemstones, the paintings can also be interpreted as abstract art.

Figure 2. Angie Crabtree at work at the AGTA show. Photo by Erin Hogarth.
The San Francisco–based artist said that all of her business, even from large corporate clients, comes from Instagram. “I’ve never paid to promote,” Crabtree said. “I’m just very fortunate for that.” Instagram also allows her to sell her own work instead of relying on galleries, which take a sizeable cut (typically around 50%). “That’s hard for artists,” she said. “Because of social media, artists have the opportunity to promote and market themselves.”
Crabtree grew up on a ranch in Sonoma County, California, and was interested in nature and geology from a young age. Her grandfather used to go gold mining, and she would collect obsidian and other rocks along the way. She began painting and taking art classes at the age of five, and by 12 she was teaching painting. She attended an arts high school and college, studied abroad at Amsterdam’s Gerrit Rietveld Academie, and graduated from the San Francisco Art Institute in 2009.
In 2012, while working as a high school art teacher, she did her first gemstone painting—a diamond portrait for an art gallery. She began painting different diamond cuts and posted them to Instagram. Soon people were asking for portraits of their engagement rings and other special stones. “That’s when it really took off,” she said.
One of the first people she met in the industry—via Instagram—was gemstone cutter Jean-Noel Soni of Top Notch Faceting. He told her about the gem industry and “completely opened my eyes,” she said. “That’s when I just fell in love with the whole thing.”
In 2015, she established her business and quit her teaching job. “It was a pretty big leap,” she said. “It’s scary for any artist to do that.” Within the first year, she was commissioned by Chopard and Forevermark to paint large series. Since then, business has grown to the point that she now has a studio manager who handles sales, accounting, and communication.
In 2018, Crabtree painted her first colored stone: an opal. “I wanted something a little bit more expressive and organic,” she said. Then came a tsavorite and an alexandrite, and she has since moved into sapphires and other stones. She plans to eventually paint minerals and other natural objects.

	Gemstone portrait artist Angie Crabtree

Crabtree was trained in realism, but she said her biggest struggle has been understanding gemstone proportions and facet dimensions. She has consulted industry experts to learn how to use the correct dimensions and ratios for the stones in her paintings. She often does not see the actual stones—most clients send her photographs. Painting accurate colors can be challenging, she said, because of the way a gemstone’s color changes with movement and light. Mixing color palettes is a laborious process: She will mix 30 or so colors and write down each color recipe for future use. “People think being an artist is painting all day every day, and it’s not,” she said. “It’s numbers and talking to people, and it’s sales and it’s promotion. Even the cleanup and setup takes forever.”
Crabtree has two autoimmune diseases. “There are certain days where I wake up and my hands are just stuck in fists. Sometimes I can’t walk. Sometimes I can’t open my paint,” she said. “But I do what I love, and I get to create my own hours, and I get to travel. So I make it work and stay positive.” Source: GIA @topic:10


Title: Fall 2002 G&G Book Reviews Abstract: “From Mine to Mistress: Corporate Strategies and Government Policies in the International Diamond Industry”
By Chaim Even-Zohar, 555 pp., publ. by Mining Journal Books Ltd., Edenbridge, England. US$495.00

“Light & Stone: Highlights from the Scott Gem Collection”
Photography by Harold and Erica Van Pelt, commentary by Peter C. Keller and Michael M. Scott, publ. by the Bowers Museum of Cultural Art, Santa Ana, California, 2002. US$25.00

“Gemstones Quality and Value, Volume 2”
By Yasukazu Suwa, 144 pp., illus., publ. by Sekai Bunka Publishing Inc., Tokyo, (2nd ed., English translation) 2002. US$95.00

“Murzinka: Alabashka Pegmatite Field”
By Valentina I. Popova, Vladimir A. Popov, and Alexander A. Kanonerov, illus., 136 pp., Vol. 5 of the Mineralogical Almanac series, publ. by Ocean Pictures Ltd., Russia, 2002. US$39.95

“Gemstones and Other Unique Minerals and Rocks of Wyoming: A Field Guide for Collectors”
By W. Dan Hausel and Wayne M. Sutherland, illus., 268 pp., Bulletin 71, Wyoming State Geological Survey, Laramie, 2000. US$20.00

To view the full section, download the PDF above. Source: GIA @topic:7


Title: Winter 2004 G&G Book Reviews Abstract: “Bernd Munsteiner: Reflexionen in Stein [Reflections in Stone]”
Edited by Wilhelm Lindemann, 224 pp., illus., publ. by Arnoldsche, Stuttgart, Germany, 2004 (in German and English). US$75.00

“Illustrated Guide to Jewelry Appraising, 3rd Edition”
By Anna Miller, 200 pp., illus., publ. by GemStone Press, Woodstock, VT, 2004. US$39.99

“Magic World: Inclusions in Quartz”
By Jaroslav Hyrsl and Gerhard Niedermayr, 240 pp., illus., publ. by Bode Verlag, Haltern, Germany, 2003 [German and English]. € 49.00

“Minerals: Their Constitution and Origin”
By Hans-Rudolf Wenk and Andrei Bulakh, 668 pp., illus., publ. by Cambridge University Press, Cambridge, United Kingdom, 2004. US$130.00 (hardcover); US$70.00 (softbound)

“Rocks Pebbles and Stones: Confessions of a Private Jeweler”
By Fred Feldmesser, 100 pp., publ. by Farrington Press, Boston, 2004. US$30.00 (E-mail: parker@ feldmesser.com)

To view the full section, download the PDF above. Source: GIA @topic:10


Title: Composite Amber with an Unusual Structure Abstract: Figure 1. This pebble-shaped amber composite had a total weight of 9.12 g. Photo by Haibo Li.

With amber emerging as one of the most popular gems in the Chinese jewelry market, the quality of imitations also appears to be on the rise. Many of these simulants are composites consisting of two or more substances, such as amber, copal, artificial resin, and plastic, joined together as a finished piece. Some composites incorporate small amber fragments. Manufacturers may also embed insect or lizard inclusions (Winter 2005 GNI, pp. 361–362). One notable composite amber specimen, a polished pebble-shaped pendant (figure 1), was recently identified at the National Gemstone Training Center (NGTC) lab in Beijing.
This specimen displayed no clear plane separating the two materials; instead there appeared to be an intersecting mixture of amber and polymer resin. The natural amber core had been covered by an outer shell of polymer resin, and about one-third of the natural amber was still exposed. Some of the small exposed portions were large enough for examination and identification. The most interesting aspect of the specimen was its pair of insect inclusions, one occurring naturally and the other artificially (figure 2).

FIgure 2. The smaller insect, circled in green, appeared in the natural amber part of the
composite, while the larger one was artificially embedded in the surrounding resin. Photo by Haibo Li.
The specimen had a waxy luster. Reflected light displayed scratches on the surface, suggesting a low hardness. It was relatively easy to observe the boundary between the natural and artificial resin sections using reflected light. Unlike most intersections found in such pieces, there were no air bubbles or other features, only clear lines. We also saw some small circular areas using transmitted and reflected light. These proved to be natural amber sections, both on the surface and within the sample, that had been polished and exposed during fashioning. The entire structure of this specimen was an intersection of two substances, identified as natural amber and polymer resin.
Observed under the microscope with transmitted light, part of the sample showed reddish brown curved lines; these were flow lines from natural amber. The two parts of the composite were clearly visible. The top part consisted of natural amber with a naturally deposited insect inclusion. The insect was translucent and partially broken. The larger insect inclusion in the bottom part was in much better condition, with an opaque transparency and clearer outline. The air bubbles around the larger insect were more spherical and concentrated, which is not typically seen in natural amber.
Under UV light, the composite gave an uneven fluorescence to long- and short-wave UV. The amber part showed a blue-white fluorescence, while the artificial resin fluoresced yellowish green.
To confirm the identity of the two different materials, we analyzed their infrared spectra (figure 3). Spectrum A displays main peaks at 1734.90 and 1160.99 cm–1, typical of Baltic region amber. Spectrum B shows a series of peaks; after comparison with spectra of amber, copal and some other synthetic materials, we used spectrum B to identify this sample as polymer resin. With its combination of natural and imitation amber, accompanied by natural and artificial insect inclusions, the piece presented an interesting identification study.

Figure 3. Reflected infrared spectra of the two parts of the specimen, with Kramers-Kronig (K-K) transformation method applied. Spectrum A represents natural amber, with typical peaks circled in green; spectrum B reveals many peaks, indicating the presence of polymer resin. Source: GIA @topic:12


Title: Spring 1999 G&G Book Reviews Abstract: “Arab Roots of Gemology—Ahmad ibn Yusuf al Tifaschi’s Best
Thoughts on the Best of Stones”
Translated with comments by Samar Najm Abul Huda, 271 pp., illus., publ. by Scarecrow Press, Lanham, MD, 1998. US$45.00

“L’e Meraude: Connais-Sances Actuelles et Prospectives [The Emerald: Current and Prospective Knowledge]”
Edited by Didier Giard, 235 pp., illus., publ. by Association Française de Gemmologie [gemmes@animasoft.fr], Paris, 1998 (softbound; in French, with partial English translations). 350.00 FF (about US$57.00)

“The Great Encyclopedia of Precious and Decorative Stones”
By Nikodem Sobczak and Tomasz Sobczak, 422 pp., illus., publ. by National Science Publishers, Warsaw, 1998 (in Polish), US$20

“Larousse des Pierres Précieuses”
By Pierre Bariand and Jean-Paul Poirot, 287 pp., illus., publ. by Larousse-Bordas, Paris, 1998 (in French), 250.00 FF (about US$42.00)

“Standards & Applications for Diamond Report/Gemstone Report/Test Report”
By SSEF Swiss Gemmological Institute, 118 pp., illus., publ. by SSEF, Basel, Switzerland, 1998, US$65.00

To view the full section, download the PDF above. Source: GIA @topic:7


Title: Fall 2008 G&G Book Reviews Abstract: “American Mineral Treasures”
By Gloria A. Staebler and Wendell E. Wilson, Eds., 354 pp., illus., publ. by Lithographie LLC [www.lithographie.org], East Hampton, CT, 2008. US$85.00

“The Diamond Handbook: A Practical Guide to Diamond Evaluation, 2nd Ed.”
By Renée Newman, 186 pp., illus., publ. by International Jewelry Publications [www.reneenewman.com], Los Angeles, 2007. US$19.95

“Gems of the World”
By Cally Oldershaw, 256 pp., illus., publ. by Firefly Books [www.fireflybooks.com], Buffalo, NY, 2008. $35.00

“Gems & Minerals”
By Andreas Landmann, 176 pp., illus., publ. by Schiffer Press, Atglen, PA, 2008. $29.99

“Southwestern Indian Jewelry: Crafting New Traditions”
By Dexter Cirillo, photography by Addison Doty, 240 pp., illus., publ. by Rizzoli International Publishers [www.rizzoliusa.com], New York, 2008. US$55.00

“Fleischer’s Glossary of Mineral Species 2008”
By Malcolm E. Back and Joseph A. Mandarino, 345 pp., publ. by The Mineralogical Record [www.minrec.org], Tucson, AZ, 2008, US$26.00

“Gemstones: Enchanting Gifts of Nature”
By R. V. Karanth, 48 pp., illus., publ. by the Geological Society of India [www.geosocindia.org], Bangalore, 2008, US$20.00

“Amazonite: Mineralogy, Crystal Chemistry, Typomorphic Features”
By M. N. Oustooumov, A. N. Platonov, and V. A. Popov, 253 pp., illus., publ. by Nedra, Moscow, 2008, Ru578 [in Russian]

“Infrared Reflection Spectrometry in Advanced Mineralogy, Gemology and Archaeometry”
By Mikhail Oustooumov, 89 pp., illus., publ. by the National University of Mexico Institute of Geophysics [www.igeofcu.unam.mx], Mexico City, 2007 [in Spanish]

“Traditional Jewelry of India”
By Oppi Untracht, 431 pp., illus., publ. by Thames & Hudson [thamesandhudsonusa.com], New York, 2008, US$49.95

To view the full section, download the PDF above. Source: GIA @topic:7


Title: Diamond Growth from C–H–N–O Recycled Fluids in the Lithosphere: Evidence from CH4 Micro-inclusions and δ13C–δ15N–N Content in Marange Mixed-habit Diamonds Abstract: This article was published in Volume 265, Lithos, Pages 68-81.
Abstract
Mixed-habit (octahdedral + cuboid) diamonds from the Marange alluvial deposits in the eastern Zimbabwe craton have high nitrogen and hydrogen content that provides an opportunity to evaluate diamond growth mechanisms and C-N-H-O bearing fluids in the lithospheric keel. Light grey cuboid sectors with hydrogen-containing defects, trap abundant dispersed CH4 inclusions (Ra- man peaks at 2917 cm−1) associated with graphite (Raman peaks at 1580 cm−1). Clear octahedral sectors are richer in nitrogen and free of any such inclusions. Core to rim co-variations of δ13C- δ15N and N content can be explained by a mixing trend between earlier fluids that are CH4-rich and later fluids that are more CO3 - or CO2-rich. Marange diamonds have limited overall δ13C variation, but do show fractionation during growth towards higher δ13C values. This trend can be explained by diamond precipitation from mixed CH4 and CO2 fluids, where isotopic fractionation occurs as the amount of fluid wanes. Calculated δ15N values for diamond source fluids evolving in this manner are between +2.3 and +6.4 ‰. These N isotopic compositions require CH4-rich and CO3 -/CO2 -rich ’end-member’ fluids to have a recycled metasedimentary component perhaps introduced with subduction of eclogite.

Purchase the full article.
aGemological Institute of America, 50 West 47th Street, New York City, NY 10036, USA
bDepartment of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road NW, Washington, DC 20015, USA
cCanadian Centre for Isotopic Microanalysis, University of Alberta, 1-26 Earth Sciences Building, Edmonton, AB T6G 2E3, Canada

dGeophysical Laboratory, Carnegie Institution for Science, 5251 Broad Branch Road, N.W., Washington, DC 20015, USA Source: GIA @topic:1


Title: Winter 2007 G&G Book Reviews Abstract: “Jewels: A Secret History”
By Victoria Finlay, 472 pp., illus., publ. by Ballantine Books, New York, 2006. US$25.95

“Fine Minerals of China: A Guide to Mineral Localities”
By Guanghua Liu, 366 pp., illus., publ. by AAA Minerals AG, Switzerland, 2006. US$148.00

“The Jewelry Handbook: How to Select, Wear & Care for Jewelry”
By Renée Newman, 177 pp., illus., publ. by International Jewelry Publications, Los Angeles, 2007. $19.95

“The Pink Pearl: A Natural Treasure of the Caribbean”
By Hubert Bari after the text by David Federman, 173 pp., illus., publ. by Skira Editore S.p.A. [www.rizzoliusa.com], Milan, Italy, 2007. US$58.00

“Opal: The Phenomenal Gemstone”
By J. Clifford, P. Clifford, A. Frazier, S. Frazier, B. P. Gaber, C. J. Gaber, G. Neumeier, and G. Staebler, Eds., transl. by G. Neumeier, 108 pp., illus., publ. by Lithographie LLC, East Hampton, CN, 2007, US$40.00

“Namibia, 2nd Ed.”
By L. von Bezing, R. Bode, and S. Jahn, 856 pp., illus., publ. by Bode Verlag [www.bodeverlag.de], Haltern, Germany, 2007, US$158.00

To view the full section, download the PDF above. Source: GIA @topic:10


Title: Spring 2011 G&G Book Reviews Abstract: “Pearls”
By Hubert Bari and David Lam, 336 pp., illus., publ. by Skira Editore [www.skira.net], Milan, Italy, 2010. US$85.00

“Terra Spinel Terra Firma”
By Vladyslav Y. Yavorsky with Richard W. Hughes, 204 pp., illus., privately published [www.spinelbook.com], 2010. US$95.00

“Colour of Paradise: The Emerald in the Age of Gunpowder Empires”
By Kris E. Lane, 280 pp., illus., publ. by Yale University Press [www.yalepress.yale.edu], New Haven, CT, and London, 2010. US$40.00

“Twentieth-Century Jewellery: From Art Nouveau to Contemporary Design in Europe and the United States”
By Alba Cappellieri, 248 pp., illus., publ. by Skira Editore [www.skira. net], Milan, 2010. US$85.00

“Jewellery from the Orient: Treasures from the Bir Collection”
By Wolf-Dieter Siewert, 320 pp., illus., publ. by Arnoldsche Art Publishers [www.arnoldsche.com], Stuggart, Germany, 2009. US$85.00

To view the full section, download the PDF above. Source: GIA @topic:6


Title: Fall 2000 G&G Book Reviews Abstract: “The Microworld of Diamonds”
By John I. Koivula, 157 pp., illus., publ. by Gemworld International, Northbrook, IL, 2000. US$95.00

“Gemstones: Quality and Value, Volume 1”
By Yasukazu Suwa, 143 pp., illus., publ. by Sekai Bunka Publishing, Tokyo (2nd ed., English translation), 1999. US$84.00

“The Diamond Formula— Diamond Synthesis: A Gemmological Perspective”
By Amanda S. Barnard, 166 pp., illus., publ. by Butterworth-Heinemann, Oxford, England, 2000. US$39.95

“Gems and Gem Industry in India.”
By R. V. Karanth, 406 pp., illus., publ. by the Geological Society of India, Bangalore, India, 2000. US$75.00 (hardbound), US$60.00 (paperback). E-mail: gsocind@bgl.vsnl.net.in

“Black Opal”
By Greg Pardey, hardcover, 204 pp., illus., publ. by GP Creations, Urungan, Queensland, Australia, 1999. With video (running time 1 hour 52 min.). US$99.95. www.gpcreations.senet.com.au

“Diamonds and Mantle Source Rocks in the Wyoming Craton with a Discussion of Other U.S. Occurrences”
by W. Dan Hausel, Report of Investigations No. 53, 93 pp., illus., publ. by the Wyoming State Geological Survey, Laramie, WY, 1998, US$10.00

To view the full section, download the PDF above. Source: GIA @topic:7


Title: Winter 1999 G&G Book Reviews Abstract: “Rock Crystal Treasures From Antiquity to Today”
By Sylvie Raulet, 240 pp., illus., publ. by Vendome Press, New York, 1999. US$75.00

“Beyond Price—Pearls and Pearl Fishing: Origins to the Age of Discoveries”
By R.A. Donkin, 448 pp., illus., publ. by the American Philosophical Society, Philadelphia, PA, 1998. US$45.00

“Amber”
By Andrew Ross, 73 pp., illus., publ. by the Harvard University Press, Cambridge, MA, 1998. US$12.95

“Gem Minerals of Victoria”
By William D. Birch and Dermot A. Henry, 120 pp., illus., Special Publication No. 4 of the Mineralogical Society of Victoria, Melbourne, 1997. Aus$34.95

To view the full section, download the PDF above. Source: GIA @topic:10


Title: Third Annual Gianmaria Buccellati Foundation Award Winner Abstract: Yi-Hsuan Chiang’s design of an amethyst, diamond, moonstone, conch pearls, coral, black opal, and baroque pearl necklace won the third annual Gianmaria Buccellati Foundation Award. Chiang is a graduate of the Jewelry Design program at GIA in Taiwan.
Yi-Hsuan Chiang, a graduate of GIA’s Jewelry Design program in Taiwan, received the third annual Gianmaria Buccellati Foundation Award for Excellence in Jewelry Design during the Tucson shows. More than 200 students competed this year, and Chiang was one of 18 finalists from seven GIA campuses. Her winning design, of a necklace depicting a butterfly that has fallen into a spider’s web, featured amethyst, diamond, moonstone, conch pearls, coral, black opal, and baroque pearl (see above).
Chiang will travel to Italy to meet Rosa Maria Bresciani Buccellati, president of the foundation, and visit its collection.
Larry French of the foundation said, “The designs that were selected as the 18 finalists and exhibited in Tucson beautifully illustrate the passion and dedication of those who created them. It is in honor of Gianmaria Buccellati’s name that we will welcome, as our guest, Ms. Chiang to Italy.”
The 2020 Gianmaria Buccellati Foundation Award for Excellence in Jewelry Design competition is underway and open to students in GIA’s Jewelry Design courses who meet the eligibility requirements. For more information, visit gia.edu/buccellati-foundation-award-jewelry-design. Source: GIA @topic:6


Title: Luxury Firms Adjust to the Era of Diminished Opulence Abstract: De Grisogono’s “Crazymals” collection introduced in Basel combines humor and craftsmanship to a luxury line. This pink flamingo ring is 18k gold, pink sapphires and colorless diamonds. Courtesy of De Grisogono

	Business at the March 23-30 Baselworld Fair was challenging for many exhibitors, even though luxury jewelry designers have been doing some serious rethinking and following the lead of the watch brands away from the blingy, gem-laden look to a more artistic approach. This was in evidence throughout the 2017 edition of Baselworld, which had its own clash with market realities this year.

	In addition to leading watch brands, the fair attracts top luxury jewelry brands and dealers of very high end gemstones – fancy color diamonds, colorless diamonds over 10 carats, and fine, untreated colored gems.

	Many fancy pink (including goods from Argyle’s three previous tender auctions), blue and yellow diamonds were available in the gemstone hall. Even the two largest Fancy Vivid violet diamonds in the market today were on display. In addition, a number of 10 carat-plus D Fl Type IIa diamonds; several Kashmir sapphires, ranging in price from $1 million to $7.5 million; and arrays of unheated Burmese rubies, including a necklace offered for $35 million, were spotted.

	While the array of such rare gems is unmatched by any venue in the world, buying was spotty. Some exhibitors with established clienteles, who were offering fine quality goods in the more mainstream market, made their sales goals. Most exhibitors at the extreme top end struggled. Also, the buyer count continued to slide this year as Chinese buyers, who had been aggressive luxury consumers, showed up in fewer numbers, and investors looking to buy rare gemstones have become wary of lofty prices.

	There were a variety of opinions as to why. Some felt that prices, which exceed $1 million per carat for fancy pink and blue diamonds, have peaked, making investors and extremely wealthy jewelry buyers reticent about buying. Others claimed that unsettled political and economic conditions in most major markets have made buyers skittish for the moment. Both camps, however, agreed that lowering prices on such goods was not an option because of the prices dealers had paid for such goods.

	Luxury jewelry houses have adapted to the mood today, stressing craftsmanship and design innovation in addition to the gem-intensive lines they are known for.

	De Grisogono, based in Geneva, introduced, among several newly-designed collections, a line of rings and pendants entitled “Crazymals,” which are quirky, amusing figures set with small diamonds, black diamonds and various colored gems.

	The company’s founder, Fawaz Gruosi, acknowledged the changes in the luxury market, but stressed that collections like Crazymals have the same attention to detail as high jewelry pieces. “In this collection, a little animal is a very sophisticated piece of jewelry,” he said.

	Another more traditional line is its India collection of necklaces and earrings featuring drop-shaped white opal, turquoise or onyx set in white gold and accented with diamonds set in a dense wild setting. As with the Crazymals, he pointed out the attention to craftsmanship that goes with each piece. Gruosi stressed that his company still does much of its business in very large diamonds – they sold a pair of 20 carat (ct) D Fl heart-shaped stones at the show.

	“These (major gems) will always have an appeal, especially as a financial asset,” he noted. “If something happens, [owners] can take these pieces anywhere in the world.”

	At this level – above eight million dollars – “You can only offer the absolute best and these goods are very, very difficult to find,” he said.

	Ian Harebottle, CEO of Gemfields, which owns Fabergé, said artistry and craftsmanship are more important than ever in the luxury market.

	“Large gems are becoming increasingly commoditized, so the way forward is to add value with craftsmanship and design,” he said.

	He cited the fine art market: “Some paintings sell for hundreds of millions of dollars. How much are the pigment, canvas and frame worth? And the most expensive diamond ever sold got only a fraction of what these works of art sell for.”

	Reena Ahluwalia, who created the Coronet by Reena diamond collection for Hong Kong-based Aaron Shum Jewellers, added another element. “The day when women dressed in formal attire wearing their jewels has passed for the most part,” she said. “Today they are less formal and want pieces that express their individuality that they can wear on the go.”

	Her Coronet collection features melee diamonds set into mobile elements to create scintillation, without using large gemstones.

	Other exhibitors employed carved, cabochon and drop-cut gem materials to create bolder, more fashion-oriented looks for wearable style in place of wearable wealth. For example, Paul Wild, of Idar-Oberstein, Germany, set drop-cut mandarin garnets into carved pink opal and similarly, cut aquamarines into carved green chrysoprase.

At Baselworld, Paul Wild of Idar-Oberstein, Germany offered a collection drop cut mandarin garnets set into carved pink opal for a necklace. Courtesy of Paul Wild. Photo Russell Shor/GIA

	Like the luxury market, the Baselworld fair itself has had to adjust to the era of diminished opulence. Between last year’s fair and this year’s, nearly 15% of exhibitors (some 200) pulled out. Nearly all of the international section, except for the Hong Kong contingent, was gone, as were many major Italian jewelry houses that populated the “Brand” hall. Several former exhibitors who attended the show as buyers said the increasing expense of the show, which has risen dramatically following the $500 million refurbishment three years ago, coupled with declining sales, made it impossible to remain.

	The fair created a special jewelry designers section with boutique-sized spaces for new and smaller companies in one of the large abandoned spaces, but with so many gaps in the exhibition areas, the decline was obvious.

	Still, fair management held firm at a contentious press conference during the opening, saying most of the companies that left did not meet show standards. Baselworld management relented by the end of the fair, however, and cut two days from the eight day show next year, lowering exhibitor costs accordingly.

	AUCTIONS

	The April 4 sale of the 59.60 ct Pink Star diamond to the Hong Kong-based retailer Chow Tai Fook for $71 million ends a long chapter for this stone – the most expensive ever sold at auction. Originally known at the Steinmetz Pink, after the first owner and polisher of the diamond, Sotheby’s sold the GIA-graded Fancy Vivid pink diamond for $82 million at its November 2015 Hong Kong sale. The buyer defaulted four months later, however, and the auction house was obliged to buy in the diamond for a reported $70 million.

	The diamond remained with the auction house until the April 4 sale. While this diamond now holds the price record for any gemstone, its per-carat price, $1.2 million, is half of what similarly graded diamonds have fetched in the recent past and less than one-third of the per-carat price of the previous record holder, the 14.69 ct Oppenheimer Blue that sold for just under $4 million per carat.

The GIA-graded 59.60 ct Pink Star diamond sold for $71 million at the April 4 Sotheby's auction in Hong Kong. Courtesy Sotheby's

	MARKET

	De Beers’ April cycle (sight) was valued at $580 million, significantly lower than the $660 million allocated at the April 2016 sale. The number may increase, however, as the company often sells goods outside the cycle system.

	De Beers said demand for rough was strong following a positive Hong Kong show. The company held the line on prices and there was no word of clients declining or deferring purchases. Source: GIA @topic:8


Title: GIA’s Museum Team Creates Magic for New York Campus Abstract: GIA Museum Curator Terri Ottaway with the rock crystal quartz specimens that serve as the foundation for the newest display at GIA’s campus in New York City. Photo by McKenzie Santimer

	How do you “wow” people who have seen it all?

	That was the question on McKenzie Santimer’s mind in 2014 as she began to think about how to transform a feature case at GIA’s New York campus into a display that would “engage, inspire and promote the gem and jewelry industry."

	Santimer, GIA’s manager of exhibits and in-kind gifts, and Terri Ottaway, GIA museum curator, knew stopping students in their tracks would be no small order. The Institute’s New York campus is perched in the heart of the city’s Diamond District on 47th Street, near the high-end displays of Fifth Avenue.

	Students walk by dazzling displays every day on their way to class.

	On top of that, the GIA museum team is based at the Institute’s Carlsbad, California, world headquarters. Nearly all of the planning for this exhibit would take place 3,000 miles from its installation site.

	A newly released time-lapse video by GIA shows how the pair meticulously constructed a display full of award-winning diamonds, huge rock crystal quartz, unusual carved gems and pieces of jewelry representing some of the most recognizable and influential eras of design.

	“It’s a slice of Carlsbad on the East Coast,” Santimer says. “We brought things to New York that you otherwise couldn’t see there.”

McKenzie Santimer, GIA’s manager of exhibits and in-kind gifts, says the ambient light in the student commons made it a challenge to “create drama” in the oversized, two-sided glass display case. Santimer is confident the exhibit will “wow Fifth Avenue walkers.” Photo by Terri Ottaway

	Design, Operational Challenges

	While the team made two years’ worth of planning look effortless, their behind-the-scenes work was anything but.

	“It’s not glamorous,” says Santimer, recounting the logistics and minutiae involved with any museum exhibit. There is the enormous task of object sourcing, as well as layouts and taping, label writing, and shipping and installation concerns. They also need to secure insurance policies that protect important pieces while they are en route and once they arrive at their destination.

	In Carlsbad, Santimer and Ottaway have some access to support staff, and a rotunda that lends itself to thematic displays that can be constructed during regular work hours. In New York, however, extra staff was limited and both ambient lighting and the double-sided glass feature case presented unusual design challenges. Nearly every aspect of the work would simply take more coordination.

	On the other hand, the space at GIA in New York presented some exciting opportunities.

	GIA occupies three floors of the two and a half-year old International Gem Tower. The eighth floor houses the education department and is accessible exclusively to the 150-plus New York students, staff and VIP visitors. There are several classrooms, a library, locker rooms and a student lounge, all with what Santimer describes as a “modern zen” aesthetic.

	“It’s a special experience for students to be there, and is almost a sanctuary and juxtaposition of the loud, vibrant city that’s just outside,” she says.

	Within that commons area is the feature display case: 20 feet long, 16 inches wide and 30 inches tall, the case is lined on one side by a hallway, and by chairs and a student lounge on the other.

McKenzie Santimer describes the student commons at GIA as having a “modern zen” aesthetic. It’s “almost a sanctuary” in the city, she says.  Photo by McKenzie Santimer

	“Students can pull up to the bar, plug in their laptops and have a cup of coffee right in front of it,” says Santimer. “It’s beautiful, but because of the two visible sides, it is a real challenge for a curator and designer to make it pretty from both viewpoints. And because of the ambient lighting, it’s very challenging to create drama.”

	The exhibit, the second in that space, would complement the already-installed 15 small, education-focused wall niche exhibits lining the hallways of the eighth floor.

	Museum Exhibit InstallationNew York Campus

	Gemological Treasures from the GIA Museum

	Though there was no formal theme, Santimer and Ottaway decided to play to GIA’s strengths and zero in on gemology.

	The pair began by replacing the petrified wood and bamboo from the previous exhibit and replacing it with a foundation of 783 carats of rock crystal and smoky quartz. They acquired the American-mined minerals – the largest of which weighs 75,000 grams and measures 12 x 9 x 7.5 inches – from the Ron Coleman Mining Company in Hot Springs, Arkansas in 2014 at the Tucson gem and mineral shows.

	“The quartz was our canvas, and buying it was a great opportunity,” Santimer says. “There aren’t many minerals large enough to fill a display this big, and there aren’t a lot of them that are pretty on both sides. Quartz crystals grow large, and it’s a mineral that we knew everyone would recognize. Terri and I see possibilities everywhere, so when we came across these crystals in Tucson, we immediately thought, ‘This would work!’”

	Next, Santimer and Ottaway decorated the quartz with a combination of 44 pieces, 29 of which are jewelry, objet d'art, and loose gemstones, from the GIA Collection.

	“We had to ask ourselves what was going to pop and stand out against the quartz,” Santimer says. “So we broke it up into smaller vignettes and motifs, based on different periods, colors and themes.

	We used 88 total carats of diamond jewelry and a smattering of art deco, contemporary and Victorian pieces, as well as unusual carved gems such as a star sapphire. There are DeBeers-award-winning pieces and organic pieces like a cow bone brooch.”

	There is also avant-garde jewelry from Brazilian designers, South Sea pearl necklaces and snake bracelets – one made of Victorian-style jet beads, the other of 15K gold.

	The quartz pieces, in addition to serving as a foundation for the entire exhibit, represent the entire cycle of a quartz – from the rock crystals to a 202.80-gram sword-shaped letter opener and “The Cyclops,” an 8,783.50-ct flawless, colorless natural quartz gemstone with a round brilliant-cut pavilion and a step-cut crown.

View Gallery

	Since the commons area is in use during the week, Santimer and Ottaway had to work back-to-back weekends, and set up a staging area in an unused classroom. And since only one side of the feature case has doors, they had to creatively fit themselves into awkward spaces and narrow openings during the installation.

	As the time-lapse video shows, the scope of their task was large, but resulted in a one-of-a-kind exhibit.

	“We had very high expectations and are very proud of this display,” says Santimer, who is already thinking about how to “up the ante” when it comes down in two to three years. “We feel like this exhibit is perfectly at home in New York and are confident that we could ‘wow’ even Fifth Avenue walkers.” Source: GIA @topic:6


Title: Hong Kong Show: Buyer-Seller Showdown on Prices Abstract: Buyers look over gemstones at the September 2015 Hong Kong Jewellery & Gem Fair last week. Photo by Russell Shor

	The September Hong Kong Jewellery & Gem Fair opened with some hard bargaining that had diamond and gemstone dealers hoping for deals.

	With the slowdown in China putting a drag on other Asian economies, expectations for this show, the world’s largest, were not high. But demand, albeit reduced, is there and retailers and jewelry manufacturers aggressively shopped for bargains from diamond dealers who had cut their inventories from very expensive rough and remain under intense pressure from their bankers to show a profit.

	The show is an important guide to how De Beers and Alrosa will conduct their final three sights/sales for the year.

	In August, De Beers cut its usual sight total by more than half to a reported $250 million and lowered prices by an average of 9% − concentrated mainly in medium- to better-quality goods that would polish out to between 0.30 carat (ct.) and 0.75 ct., where inventory levels are highest. And Alrosa, the world’s largest diamond producer by volume, followed suit, cutting volume and prices by similar amounts at its September sale.

	The results of the Hong Kong show will surely determine whether or not these two producers, which account for more nearly three quarters of the rough market, resume “normal” sales or continue to rein in supplies.

	Reports from state of Gujarat, India where the vast majority of diamond manufacturers are located, say many of those facilities have cut workers’ hours by as much as 40% because of reduced demand and high inventories, while an estimated 20,000 to 30,000 (5-7% of the workforce) have lost their jobs.

	Gujarat’s government is worried that the troubles in the diamond industry could exacerbate the existing unrest from the Patel community, which is demanding a larger share of government and academic jobs. A significant percentage of the diamond workforce belongs to this group, which had been one of the most prosperous in the region.

	Demand for emeralds remains robust. Gemfields achieved strong prices at its September auction of rough from its Kagem Mine in Zambia. The Singapore sale of 600,000 carats realized $34.7 million, for an average price of $58.42 per carat – the third highest total in the six years since the company has been auctioning Kagem material. This auction included finer quality material of various grades. The company also sells lower quality material, which is classifies as beryl, in separate sales.

RETAIL

	U.S. retail analysts were heartened by August’s improved job report and a very strong upward spike in the Conference Board’s Consumer Confidence index. The index, which had declined to 91.0 in July, rose more than 10 points to 101.5 in August as consumers grew more upbeat about the economy.

	“Consumers’ assessment of current conditions was considerably more upbeat, primarily due to a more favorable appraisal of the labor market,” said Lynn Franco, director of Economic Indicators at The Conference Board. “The uncertainty expressed last month about the short-term outlook has dissipated and consumers are once again feeling optimistic about the near future. Income expectations, however, were little improved.”

	De Beers’ executives remain “cautiously optimistic” about final quarter diamond jewelry sales.

	There are several reasons for their optimism regarding the U.S. One, the company is reviving its generic “Diamonds Are Forever” advertising campaigns it stopped several years ago. Some analysts blame lackluster diamond demand of the past five years on the ending of these campaigns.

	Second, the U.S. dollar has risen strongly among most major currencies, which helps keep prices stable here even if it does dampen demand in foreign markets. In China, for example, the diamonds from the August sight will cost 6% more because its currency declined by that much against the dollar in the past month. Source: GIA @topic:8


Title: Spring 2002 G&G Book Reviews Abstract: “Christie’s Guide to Jewellery”
By Sarah Hue-Williams, 160 pp., illus., publ. by Assouline Publishing, New York, 2002. US$18.95

“The Theory & Practice of Goldsmithing”
By Erhard Brepohl, 536 pp., illus., publ. by Brynmorgen Press, St. Portland, ME, 2001. US$70.00

“Fabergé Eggs: A Retrospective Encyclopedia”
By Will Lowes and Christel McCanless, 286 pp., illus., publ. by Scarecrow Press Inc., Lanham, MD, 2001. US$65.00

“Colored Gemstones: The Antoinette Matlins Buying Guide”
By Antoinette Matlins, 180 pp., illus., publ. by Gemstone Press, Woodstock, VT, 2001. US$16.95

“Diamonds: The Antoinette Matlins Buying Guide”
By Antoinette Matlins, 184 pp., illus., publ. by Gemstone Press, Woodstock, VT, 2001. US$16.95

“The Gem Hunter in Afghanistan”
An Epo-film production, Bristol, England, 2002. 52 minutes, available in VHS and DVD formats. US$29.95

To view the full section, download the PDF above. Source: GIA @topic:6


Title: Summer 2000 G&G Book Reviews Abstract: “Proceedings of the VIIth International Kimberlite Conference”
Edited by J. J. Gurney, J. L. Gurney, M. D. Pascoe, and S. H. Richardson, 947 pp. in two volumes, illus., publ. by Red Roof Design, Cape Town, South Africa, 1999. US$150 (plus postage)

“Gems & Jewelry Appraising, 2nd Edition”
By Anna M. Miller, 222 pp., illus., publ. by Gemstone Press, Woodstock, VT, 1999, US$39.95

“1000 Photos of Minerals and Fossils”
By Alain Eid, photography by Michel Viard, 127 pp., illus., publ. by Barron’s Educational Series, Hauppauge, NY, 2000. US$24.95

“Fire Into Ice: Charles Fipke and the Great Diamond Hunt”
By Vernon Frolick, 354 pp., illus.,
publ. by Raincoast Books, Vancouver, 1999. US$21.95

To view the full section, download the PDF above. Source: GIA @topic:10


Title: Winter 1997 G&G Book Reviews Abstract: “Creative Variations in Jewelry Design”
By Maurice P. Galli, Dominique Rivière, and Fanfan Li, 527 pp., illus., publ. by Schiffer Publishing, Atglen, PA, 1997. US$69.95

“Visual Optics: Diamond and Gem Identification Without Instruments—The Hodgkinson Method”
By Alan Hodgkinson, 50 pp., illus., publ. by Gemworld International, Northbrook, IL, 1995. US$25.00

To view the full section, download the PDF above. Source: GIA @topic:6


Title: Summer 1986 G&G Book Reviews Abstract: “Birthday Book of Gems”
By Harold and Erica Van Pelt, 128 pp., illus., publ. by Van Pelt Photographers, L. A., CA, 1986.
US$8.95

“The New World of Gold”
By Timothy Green, 290 pp., paperback, publ. by Walker and Co., New York, NY, 1984 (rev.). US$12.95

“Diamond, Ruby, Emerald, and Sapphire Facets”
By Gary Grelick, 56 pp., illus., privately published, 1985. US$5.00

“Art Nouveau Jewelry”
By Vivienne Becker, 240 pp., illus., publ. by E. P. Button, New York, NY, 1985. US$50.00

“Reviews in Mineralogy Volume 12: Fluid Inclusions”
By Edwin Roedder, 644 pp., illus., pub. by the Mineralogical Society of America, Washington, DC, 1984. US$15.00

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