Publication Year: 2001 Title: Fall 2001 Gem News International Abstract: Diamonds
            Report from the 2nd World Diamond Conference, Vancouver
            Diamonds from Copeton, Australia
Colored Stones and Organic Materials
            Maxixe-Type Green-Blue Beryls with Eye-Visible Pleochroism
            Coloration of Morganite from Pala, California
            Vanadium-Colored Beryl from China
            Mini-Faults in Chalcedony
            Recent Gem Discoveries in Pala, California
            A Statuette Containing a Large Natural Blister Pearl
            Exceptional Carpet Shell Pearl
            Tahitian “Keshi” Cultured Pearls
            Pearl Culturing in Northwest Australia
            Green Powellite from Chile
            Anhydrite Inclusion in a Ruby from Myanmar
            Ruby and Sapphire Mining at Barrington Tops, Australia
            Renewed Mining for Rubies in Nanyaseik, Northern Myanmar
            Blue-to-Green Tourmaline from Nigeria
            Nigeria as a New Source of Copper-Manganese-Bearing Tourmaline
            More on Liddicoatite from Nigeria
Synthetics and Simulants
            Laboratory-Grown Orange-to-Yellow “Langasite”
            Laboratory-Grown Pink SrLaGa3O7, a Material Related to “Langasite”
            An Unusual “Crystal” of Synthetic Ruby from Sri Lanka
            A Rare Medieval Sapphire Imitation
Announcements
            GAGTL Gem-A Conference 2001
            SimDesign 2001
            Australian Diamond Conference
            Visit Gems & Gemology Staff in Tucson
            Jewels of the Nizam
Exhibits
            Gem Museum in Sri Lanka
Pearls at the American Museum of Natural History

To view the full section, download the PDF above. @chapter:1


Publication Year: - Title: Melee: Building Blocks of Contemporary Design Abstract: Melee can be used to ornament a wide variety of contours and shapes such as on this extraordinary ring. Courtesy of JYE's International

An important element of the gem and jewelry industry, melee can create a modern look and elegant design patterns. Designers need to know about it, and so do professionals all along the value chain.

GIA defines melee (pronounced meh-lee) as small diamonds and gemstones weighing less than 1/5 carat (ct), but size ranges vary from country to country and from one segment of the trade to another. Melee are often cut into a round shape, but are available in a variety of  shapes: emerald, princess, radiant, marquise and more. New design and manufacturing technology is enabling more ornate and complicated jewelry that is in high demand.

Dealers may use sieves such as these to sort melee into different sizes.
The more diamonds in a piece of jewelry, the more sparkle it has. Due to their small size, melee diamonds are inexpensive when compared to larger diamond center stones, so they are often generously used in engagement ring designs to add brightness and scintillation.

Melee are often used to enhance nearby stones and to make decorative patterns. They are also used to add sparkle to bracelets, necklaces, earrings, watches and other types of jewelry.
Melee color grades are usually not very detailed: “Face up white” (D-H colors) and “Top light browns” (M-O colors) are examples. Clarity grades are described similarly, such as “Eye clean” for no visible inclusions to the unaided eye. Jewelry manufacturers then strive to match the color of the center stone to the color of melee.

There are approximately 9.50 ct of melee (791 round diamonds) in this 18K white gold bracelet. If the melee were not carefully matched for color, the bracelet would lose much of its elegant beauty. Courtesy of Uneek
Melee diamonds are produced in large quantities in factories that use the latest diamond cutting equipment. High-tech machines have reduced the amount of labor required and improved the quality of the finished product, but cutting and sorting melee is still a labor intensive business. The city of Surat in India is an important manufacturing hub for diamonds, including melee which are faceted, sorted, and sold in parcels of 100 carats or more to jewelry manufacturers (parcels can have over 400 melee). A single piece of jewelry can have dozens or even hundreds of melee stones.

Just like larger carat diamonds, the ability to detect simulants and synthetic (lab-grown) melee diamonds is important to the trade. In the past few years, companies have introduced automated systems like GIA’s Melee Analysis Service, which cost-effectively analyzes and sorts natural diamond melee from synthetic.

Melee in Jewelry Design

Creative jewelry designers are using tiny pieces of melee to make a big statement. They’re incorporating it to add scintillation to engagement rings, and to create a realistic or whimsical look in large, organic curved surfaces (colored gems are often used as melee).

The gradations of color in this ring was accomplished by cutting benitoite into melee. Courtesy of the Columbia Gem House Inc.
In engagement rings, matching the color of melee to the color of the center stone is important. When it does match, the results can be breathtaking. A halo made of melee can make the center stone appear larger. Decorative patterns of melee can create visual interest. But if the melee is darker or lighter than the center stone it’s likely to create an unattractive appearance.

Melee used to create a halo can add additional sparkle and make the center stone appear larger. This platinum engagement ring features a 1 ct center stone with 0.5 total carat weight of melee in the halo and shank. Courtesy of Blue Nile.
When working with melee in jewelry design, it’s important to understand the difference between “carat weight” and “total carat weight,” because diamond weight is a driving factor in determining price. Total carat weight, often abbreviated (tcw) in the jewelry industry, is used to describe the combined weight of all the diamonds in a piece of jewelry that only contains diamonds. The description carat weight (ct) only applies to an individual stone, like the center stone. A ring with many small diamonds with a 2.50 tcw can cost significantly less than a solitaire engagement ring with a single diamond weighing 2.50 ct.

Common Setting Styles for Melee

Bead and Bright: Small beads hold the stones in place in this popular style of bead setting. The bead setting is surrounded by a bright-cut wall that helps to reflect light into the diamond.
Channel: This is a technique where single or multiple stones are secured between two opposing walls with channel supports below. This setting does not have beads or prongs to secure the stone.
Pavé: Another bead-style setting, pavé is setting stones in three or more rows with hand-raised beads that hold them in place.
Prong: Metal supports secure a gemstone and are part of a setting. Prong settings show more of the gemstone by using less metal than other setting styles.

Melee Design and Engineering Challenges

Using melee requires striking a balance between design and engineering. For example, placing melee in every available location on a brooch may impress customers, but if the piece is not designed for this type of application it may not be durable.

Also, setting styles such as pavé, bead and channel require the removal of metal from jewelry. However, removing too much metal from an improperly engineered piece can result in structural weakness and failure during daily wear.
GIA Quality Assurance Benchmarks (QABs™) are criteria for evaluating the design, engineering and manufacture of jewelry and are taught in the GIA Jewelry Design & Technology and Graduate Jeweler diploma programs. Here are some best practices you can use when working with melee:

Melee of different sizes (even by 0.20 millimeters (mm)) may be noticeable to a customer. Selecting similar-size diamonds is important if uniformity is part of the design.
All prong tips should be in solid contact with the gem’s crown so there are no gaps between the prong and the stone. Prong tips that are not flush can snag on clothes, scratch skin and break.
For pavé or bead and bright setting, use at least a 0.50 mm border to ensure structural integrity.
For channel-set stones, build 1.00 mm walls on either side of the stones. Then bearings can be cut into the channel walls, so that approximately 10% of the diamond is in contact with the setting.
Gold, silver and platinum have different properties. Be sure to account for the unique metallurgical properties of the metal you are using when setting melee.

GIA Quality Assurance Benchmarks highlight workmanship of semi-finished and finished jewelry. Learn how to evaluate the quality of a bead-set diamonds in the shank of a platinum ring. GIA.edu/QAB
GIA QAB™, which were developed with support and feedback from the jewelry industry, provide an objective method for evaluating the quality of semi- or fully-finished jewelry by comparing it against acknowledged criteria, and show how to set melee properly.

Challenges aside, setting melee can be very lucrative, and comes with relatively low liability for potential loss due to breakage. For professionals in other parts of the trade, melee has an importance far greater than its size. So knowing about it is essential. @chapter:29


Publication Year: 2020 Title: GIA Museum’s Tucson Exhibit Receives Two Awards Abstract: This exhibit highlighted GIA’s research into the origin of several of the most famous diamonds. Photo by McKenzie Santimer.

The GIA Museum received two awards for its exhibit at the 2020 Tucson Gem and Mineral Show. “The Science Behind World-Class Diamonds” (see above) won Best Museum Exhibit from the Tucson Gem & Mineral Society and Best Institutional Educational Award from the Friends of Mineralogy. The exhibit demonstrated how famous diamonds such as the Hope and the Cullinan originated in extreme depths of the earth’s lower mantle. The showcase featured extraordinary diamond jewelry and diamond replicas.
More than 30 cases were displayed by renowned museums including the Smithsonian Institution, LA County Museum of Natural History, and the Royal Ontario Museum. This is the second time GIA has won the award for Best Museum Exhibit, having won previously in 2016. @chapter:24


Publication Year: 1994 Title: Summer 1994 G&G Book Reviews Abstract: “The Professional's Guide to Jewelry Insurance Appraising”
By Patti J. Geolat, C. Van Northrup, and David Federman, 167 pp., illus., Vance Publishing Corp., Lincolnshire, IL, 1994. US$95.00

“Metalwork in the Arts And Crafts Tradition”
By Elyse Zorn Karlin, 272 pp., illus., publ. by Schiffer Publishing, Atglen, PA, 1993. US$69.95

“The Last Empire: De Beers, Diamonds, and the World”
By Stefan Kanfer, 409 pp., illus., publ. by Farrar, Straus & Giroux, New York, 1993. US$25.00

To view the full section, download the PDF above. @chapter:21


Publication Year: 2023 Title: Carbon Dioxide in a Brown Diamond Abstract: Figure 1. This 1.03 ct natural Fancy Dark brown diamond has uneven color zoning and abundant black inclusions. Infrared absorptions corresponding to carbon dioxide (2370 and 659 cm–1) and carbonate (1433 and 870 cm–1) were detected. Photo by Mei Yan Lai.
The Carlsbad laboratory recently examined a 1.03 ct natural Fancy Dark brown diamond with uneven color zoning and abundant black inclusions (figure 1). The diamond had infrared absorption features at 2370 and 659 cm–1, corresponding to the asymmetric stretching mode and bending mode of carbon dioxide, respectively (E. Barannik et al., “Shift of CO2-I absorption bands in diamond: A pressure or compositional effect? A FTIR mapping study,” Diamond and Related Materials, Vol. 113, 2021, article no. 108280). Diamonds containing carbon dioxide are rarely submitted for diamond grading reports, and this brown diamond is one of the few GIA has encountered. Carbon dioxide likely exists as submicroscopic solid inclusions in natural diamond (M. Schrauder and O. Navon, “Solid carbon dioxide in a natural diamond,” Nature, Vol. 365, 1993, pp. 42–44). The major infrared absorption peaks observed are shifted from the peak positions of atmospheric carbon dioxide (2350 and 667 cm–1), and the peak shift depends on pressure and the presence of impurities such as water and nitrogen in the trapped carbon dioxide inclusions (Barannik et al., 2021).

Figure 2. Microscopic examination under high magnification revealed the hexagonal shape of the black inclusions. Photomicrograph by Mei Yan Lai; field of view 1.26 mm.
Carbonate-related absorptions at 1433 and 870 cm–1 were also detected. These absorptions have previously been reported in some natural diamonds containing solid carbon dioxide inclusions (e.g., Summer 2005 Lab Notes, pp. 165–167; Barannik et al., 2021). Clusters of black hexagonal inclusions were observed in the diamond (figure 2), and the individual inclusions ranged in size from <1 to ~50 μm. Similar inclusions have been documented in some carbon dioxide–bearing natural diamonds and identified as graphite platelets (A. Shiryaev et al., “Exsolution of oxygen impurity from diamond lattice and formation of pressurized CO2-I precipitates,” Carbon Trends, Vol. 11, 2023, article no. 100270).
This brown diamond containing carbon dioxide displayed yellow fluorescence when exposed to long-wave UV. When exposed to deep UV (<230 nm), the diamond exhibited irregular surface fluorescence zoning with yellowish green, bright green, and blue colors caused by distinct lattice defects. The yellow fluorescence to long-wave UV, heterogeneous distribution of lattice defects, and irregular surface fluorescence zoning under deep-UV excitation are commonly observed in diamonds colored by the 480 nm absorption band (known as “480 nm band diamonds” in the trade; C.M. Breeding et al., “Naturally colored yellow and orange gem diamonds: The nitrogen factor,” Summer 2020 G&G, pp. 194–219). In fact, the photoluminescence (PL) spectra of this brown diamond closely resembled those of 480 nm band diamonds. The most notable PL feature detected was the broad band centered at ~680 nm, which is attributed to the vibronic emission associated with the 480 nm absorption band (A. Collins and K. Mohammed, “Optical studies of vibronic bands in yellow luminescing natural diamonds,” Journal of Physics C: Solid State Physics, Vol. 15, 1982, pp. 147–158). The similarity in spectroscopic features between carbon dioxide–bearing brown diamonds and 480 nm band diamonds has been previously reported, and a genetic relationship between the two has been suggested (T. Hainschwang et al., “HPHT treatment of CO2 containing and CO2-related brown diamonds,” Diamond and Related Materials, Vol. 17, 2008, pp. 340–351). @chapter:11


Publication Year: 1992 Title: Methods for Determining Gold Content of Jewelry Metals Abstract: Verifying the gold content of karat-gold jewelry is a problem for the entire industry. This study compares four widely available testing methods: density (measured by hydrostatic weighing), chemical reactivity (touchstone testing), capacitive decay (Tri-Electronics G-XL-18 Gold Tester), and X-ray fluorescence (Seiko Instruments SEA 2001 Jewelry Assay System). The latter three methods all proved useful within certain limitations; hydrostatic weighing was least suitable. None of these methods reliably determined gold content within the 3-ppt tolerance allowed by U.S. plumb laws. @chapter:24


Publication Year: 2016 Title: Laminated Tortoiseshell Scepter Abstract: Figure 1. This tortoiseshell scepter is from the Palais Royal collection. Photo by Tony Leung.

	“Tortoiseshell” generally refers to a material produced from the shell of the hawksbill sea turtle (T. Hainschwang and L. Leggio, “The characterization of tortoise shell and its imitations,” Spring 2006 G&G, pp. 36–52). Because of its attractive appearance, durability, and thermoplasticity, it had been widely used for jewelry, personal items, and ornamental objects since ancient times, until the international trade of new tortoiseshell was banned in the 1970s under the Convention on International Trade in Endangered Species (www.cites.org). Today, this material is seldom submitted to gemological laboratories.

	Recently, a mottled brownish orange scepter measuring 203.00 × 41.45 × 42.52 mm was submitted to GIA’s Hong Kong laboratory (figure 1). The object was adorned with white metal and numerous stones of various shapes and colors.

	Standard gemological testing revealed an RI of 1.56. In addition to the orange bodycolor with distinctive brown patches and resinous luster, the strong odor of burned protein given in hot point testing ruled out most inorganic and organic materials except the keratinous materials tortoiseshell and horn. Under magnification, the piece showed a layered structure and mottled color patches made up of numerous brownish dots of pigment (figure 2), both typical of tortoiseshell. The only remaining question was the thickness of the piece, which at 42.52 mm far exceeded tortoiseshell’s maximum thickness of 9–12 mm (Hainschwang and Leggio, 2006). The orange part of the scepter exhibited a strong blue reaction to long-wave UV radiation, with a wavy layered structure and distinct boundaries (figure 3, left), and a weaker reaction to short-wave UV. The brown patches were inert to both long-wave and short-wave UV. Taking into account the piece’s exceptional thickness and the unusual structural discontinuities observed under UV source, we concluded this material was laminated tortoiseshell.

	Figure 2. The brown patches in the tortoiseshell scepter were made up of numerous brownish spots. Photo by Xiaodan Jia; field of view 1.88 mm.

	Figure 3. Left: Under long-wave UV, the scepter showed disordered wavy layers of various thickness and boundary layers marked by structural discontinuities. Right: A natural tortoiseshell tablet displays a parallel layered structure in side view. Field of view 19.27 mm. Photos by Johnny Leung (left) and Jonathan Muyal (right).

	Further analysis by FTIR on powdered samples collected at different layers showed a keratin spectrum with predominant amide peaks at 1637, 1516, and 1236 cm–1 (figure 4), which confirmed the material was tortoiseshell (Hainschwang and Leggio, 2006). High levels of S and Cl detected by EDXRF were also consistent with known tortoiseshell samples.

	Figure 4. FTIR spectra of the tortoiseshell displayed amide peaks at 1637, 1516, and 1236 cm–1. The spectrum on the right is a closer view of the region in the red box on the left. @chapter:37


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

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

As in previous years, we identified some strong trends:

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

View Gallery

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Finally, no survey of the Tucson shows would be complete without Paula Crevoshay’s one-of-a-kind designs. This year, she showcased a bracelet featuring five large freeform fire opals, a swallowtail butterfly pin with yellow and black diamonds, an elephant pin with mother-of-pearl tusks, and a stunning cuff bracelet featuring a spectacular boulder opal centerpiece. @chapter:28


Publication Year: 2013 Title: Green Diamond, Treated with Radioactive Salt Abstract: Figure 1. This 3.17 ct round brilliant cut diamond owed its Fancy Deep green color to irradiation with radioactive salts. Photo by Jian Xin (Jae) Liao.

Recently submitted to the East Coast laboratory was a 3.17 ct round brilliant cut diamond, color graded as Fancy Deep green (figure 1). Natural diamonds of this color are very rare and desirable.

Examination with a gemological microscope revealed a very unusual surface coloration. The surface had a mottled pattern created by very shallow green staining, likely from exposure to radiation (figure 2). This unusual feature is rarely observed on natural diamond surfaces or facets. Natural radiation staining on the surface of a diamond crystal would be mostly removed during faceting.

Figure 2. Observed at 35× magnification, the diamond shows a mottled effect created by shallow green radiation stains. Photo by Jian Xin (Jae) Liao.
The stone owes all of its green color to these shallow radiation stains. Today, most artificially irradiated diamonds are treated with a low-energy electron beam. This often results in shallow color zoning that penetrates into the stone and aligns with the facet shape. In this case, the shallow staining was created using the older method of exposing the diamond to radioactive salts for an extended period of time. Mainly used on polished stones, this method leaves surface contamination.
Stones irradiated in this fashion can have residual radiation, so we tested this stone using a Geiger counter. Only background radiation was detected, indicating that the treatment likely occurred decades earlier. Thus, this diamond posed no radiation hazards. Sir William Crookes first discovered radiation’s effects on diamond color by conducting a series of experiments using radium salts in 1904. Although rarely encountered today, these types of treated diamonds still show up in the trade. A careful inspection of the surface in diffused lighting is the most effective means of revealing the diagnostic surface coloration. @chapter:11


Publication Year: 2009 Title: Gray-To-Blue-To-Violet Hydrogen-Rich Diamonds from the Argyle Mine, Australia Abstract: The Argyle diamond mine is the only known source of type IaB hydrogen- and nitrogen-rich diamonds colored gray to blue to violet. Twenty such diamonds were studied to investigate the relationships between their spectroscopic characteristics and color grades. The unusual color is the result of broad absorption bands centered at ~520–565 nm and 720–730 nm. A pronounced 551 nm band is superposed on the 520–565 nm feature. Spectral deconvolution of this feature suggests that it may be a composite, including H-related absorptions at ~545 and 563 nm and bands at 520–530 and 551 nm. The near- and mid-IR regions exhibit strong absorptions, including those related to H and N, many of which become more intense with increasing color saturation. The PL spectra exhibit peaks associated with nickel-related defects, which may play an important role in the coloration of the more violet diamonds in this group. H-rich gray-to-blue-to-violet diamonds, which are not known to be treated, can be readily separated from similar-hued diamonds that may be HPHT enhanced or synthetic.

	DATA DEPOSITORY

Supplemental Material
	Spring, 2009 @chapter:11


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

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

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

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

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

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

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

View Gallery

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

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

The 2017 GSA annual meeting is going to be held in Seattle, Washington. GSA will again host both oral and poster technical sessions. Photo by Tao Hsu/GIA @chapter:20


Publication Year: - Title: A Vivid Spring 2016 Auction Season: Sales Totals Near $800 Million Abstract: A cut-cornered, rectangular, mixed-cut Fancy Intense blue diamond, weighing approximately 24.18 carats, flanked on either side by tapered baguette-cut diamonds, weighing a total of approximately 2.36 carats, mounted in platinum. It is inscribed with “Cullinan Dream.” Photo courtesy of Christie’s

The spring 2016 auction season was one for the record books, achieving nearly $800 million in sales between March and July and featuring the costliest gemstone ever to be sold at a public sale.

Christie’s and Sotheby’s, who control over 90 percent of top-end gem and jewelry sales worldwide, broke last year’s record by more than $140 million, aided by the Oppenheimer Blue, a Fancy Vivid blue diamond that sold for $57.1 million.

Francois Curiel, chairman of Christie’s Asia, said the market still was being driven by private buyers from Russia and Asia.

A rare oval Internally Flawless Fancy Vivid blue diamond weighing 10.10 cts. Photo courtesy of Sotheby’s
The first major stone to sell this past season was the 10.10 ct. Fancy Vivid blue De Beers Millennial 4 diamond. The stone was part of De Beers’ famed diamond collection of 10 blue diamonds that were exhibited at the London Millennial Dome in 2000. A gang of thieves crashed through the dome wall with an earth-mover and attempted to steal the collection on Nov. 8, 2000. The diamonds were housed in shatterproof glass cases, however, which proved to be the gang’s undoing – the police apprehended several members as they were trying to smash the cases.

After the exhibition closed some months later, De Beers sold the collection privately. The buyer of the Millennial 4 stone, a Hong Kong resident, consigned the GIA-graded diamond for sale at Sotheby’s April 2 Hong Kong sale, where it brought $32 million, or $3.2 million per carat.

Designed by Verdura, the Jubilee Ruby ring features a 15.99 ct. oval-shaped Burmese ruby surrounded by diamonds and mounted in platinum and 18K gold. Photo courtesy of Christie’s
Several major gemstones changed hands at Christie’s in New York on April 20. The 15.99 ct. Jubilee Ruby, an unheated Burmese cushion cut, became the most expensive colored gemstone ever sold at auction in the U.S. when the high bidder paid $14.2 million for it.  Just before the ruby sold, another buyer paid $8.8 million for a 10.07 ct. Fancy Intense purple pink brilliant cut diamond and $7.2 million for a 40.43 ct. type IIa D flawless diamond. Both diamonds were graded by GIA.

A day earlier at Sotheby’s, one significant lot failed to sell. The 9.54 ct. Fancy Deep blue Shirley Temple diamond – presented to the child actress in 1940 – did not meet its $25 million reserve. Sotheby’s executives said they were confident they could sell the diamond in a private deal.

 The "Unique Pink," a 15.38 ct. natural-color, Fancy Vivid pink diamond. Graded by GIA, the diamond is a pear modified brilliant with VVS2 clarity, and classified as a Type IIa diamond.  Photo courtesy of Sotheby’s
The highest total ever achieved at a single auction occurred on May 17 when Sotheby’s realized $175.1 million at its Geneva Magnificent and Noble Jewels auction. The highlight was the Unique Pink, a 15.38 ct. Fancy Vivid pink diamond that went to a private buyer for $31.6 million, a record for a stone of that grade. The auction also featured a 6.64 ct. Fancy Intense blue diamond brooch by Alexandre Reza that sold for $13.7 million.

The Fancy Vivid blue rectangular-cut diamond, weighing approximately 14.62 cts. is flanked on either side by a trapeze-shaped diamond. It is mounted in the original platinum “Eight Shades” mounting from Verdura. GIA graded the diamond a Fancy Vivid blue, natural color, VVS1 clarity. Photo courtesy of Christie’s
While there are several diamonds carrying the Oppenheimer name, the 14.62 Fancy Vivid blue diamond that belonged to Sir Philip Oppenheimer was the one that took the title of the world’s most expensive gem ever sold at auction. The diamond, graded by GIA, was expected to sell at Christie’s May 18 Geneva sale for about $45 million, but the bidding reached $57.4 million in only 25 minutes. The buyer declined to be identified. That diamond accounted for about 40 percent of Christie’s sale total of $145 million that day, which would have been good for a world record two years ago. That auction also featured a pair of near-matching (11.96 ct. and 12.2 ct.) Fancy Vivid orange yellow ear pendants that sold for $11.6 million.

This 5.03 ct. Fancy Vivid green, named the Aurora Green, is the largest Fancy Vivid green diamond graded by GIA as of May 2016. Photo courtesy of Christie’s

At the end of May, a 5.03 Fancy Vivid green diamond brought over $16.8 million ($3.34 million per carat) at Christie’s Hong Kong sale – the highest price and per-carat amount ever paid for a green diamond. One reason for the lofty price is that the stone was tracked from mine to market, giving strong provenance for the natural origin of its green color. That auction also saw the highest price ever paid for a pair of ruby earrings, $11.6 million, weighing 10.02 ct. and 9.09 ct. That works out to just over $607,000 per carat. Also, the highest price ever paid for a bracelet at auction − $7.26 million − went for a Cartier Art Deco and sapphire piece.
Late-Season Auctions

Customarily, the last major auctions are held in mid-to-late May but this was an unusual season. Christie’s added the 24.18 ct. Fancy Intense blue Cullinan Dream diamond to its June 9 New York sale, where it realized $25.3 million. The GIA-graded diamond was the largest of that grade ever auctioned and the first to be sold from a 122 ct. rough that was discovered several years ago in South Africa’s historic Cullinan Mine.

The Cullinan mine has been the source of many of the world’s largest diamonds, including the largest diamond ever found  – 3,106 cts., since the mine opened in 1903.

This 1,109 carat rough Type IIa diamond, named Lesedi La Rona, was unearthed in Botswana last year – the second largest ever found. Photo courtesy of Lucara Diamond

The second largest rough diamond ever found – the Lesedi La Rona – came last year at Lucara Diamond Corp., Kerowe Mine in Botswana. It was only the second gem-quality rough diamond ever to break the thousand-carat mark, weighing in at 1,109 cts. While mining companies usually sell rough diamonds through their own auctions or contract price sight sales, Lucara consigned the diamond and four other rough diamonds weighing just over 5 carats each to Sotheby’s for sale on June 29 in London, where it was expected to bring in excess of $70 million.

In what was supposed to be the climactic close to this record auction season, auctioneer David Bennett opened the bidding at $50 million and the price climbed slowly before stalling at $61 million. Bennett kept his hammer poised for several minutes announcing "last chance” before bringing it down and informing the audience that the stone failed to meet the reserve price and did not sell. @chapter:30


Publication Year: 2016 Title: Book Review: Swarovski: Celebrating a History of Collaboration in Fashion, Jewelry, Performance and Design Abstract: By Deborah Landis and Vivienne Becker, hardcover, 352 pp., illus., publ. by Rizzoli, New York, NY, 2015, US$95.00.

	This book is sumptuous in its presentation. Its production quality is elegant from the silver cardstock end papers to the beautiful photography and fancy gatefold spreads. It will display nicely on your coffee table, weighing in at a whopping six pounds.

	Beyond the dazzling first impression, the value of the book is really in the eye of the beholder. If you are looking for an in-depth history of the use of Swarovski crystals in jewelry, or even simply a look at the firm’s contemporary jewelry output, this book may not be for you. The photographs are gorgeous and the creations divine, but the text lacks in substance.

	The book is divided into four sections: Fashion, Jewelry, Performance, and Design. The jewelry section has a nice essay by noted jewelry historian Vivienne Becker. It is oddly printed on mini pages and bound in front of the oversize pages containing images of the jewelry. It seems to say the story is less important than the imagery. And the jewelry pieces shown are over-the-top creations rather than a representative gallery of the Swarovski crystals used in jewelry since the end of the 19th century. Is it really necessary to show a high-style ring fashioned of Swarovski crystals as a 10 in. × 12.5 in. photo? The essay itself is a useful discussion of Swarovski’s role in establishing the costume jewelry world. But the author’s voice is not continued throughout the many images that are shown through captions, which would have been useful.

	It is great fun to see Michael Jackson’s crystal-covered glove, pieces created for major fashion houses, the original crystal chandelier lighting commissioned for the Metropolitan Opera House in New York, and more. Yet this book offers little information for those interested in jewelry specifically. The jewelry actually depicted in this book consists mostly of one-of-a-kind pieces worn on the runway or sold to an elite audience through couture houses, not jewelry most of us will ever see. @chapter:16


Publication Year: 2023 Title: An Unusual Partially Non-Nacreous Pinctada radiata Natural Blister Pearl Abstract: Figure 1. Pinctada radiata shell with a natural blister pearl measuring approximately 11.39 × 9.31 × 8.69 mm. Photo by Gaurav Bera.
The vast majority of pearls produced by the different Pinctada species display a lustrous nacreous surface structure. However, a small percentage of these pearls exhibit non-nacreous surfaces. GIA’s Mumbai laboratory received one very interesting example for scientific examination: a partially non-nacreous natural blister pearl, obtained from the waters of Bahrain by a noted pearl diver in March 2023.
The shell weighed 21 g and measured approximately 64.55 × 63.90 × 7.72 mm. The back of the shell showed fine layered striations toward one end and areas of massive parasite holes toward the center and hinge area. The inner surface was silvery cream in color with strong orient and held a large light cream and brownish black baroque pearl, measuring approximately 11.39 × 9.31 × 8.69 mm, attached close to the upper mantle-lip area (figure 1). This blister pearl was very unusual compared to those typically found in the Pinctada radiata mollusk. Viewed under 40× magnification, the inner shell’s brown edges exhibited columnar calcite honeycomb-like structures, while the white portion displayed the typical platy structure of fine nacreous overlapping aragonite platelets, presenting a chalky appearance near the hinge. Surrounding the central blister pearl was a yellowish brown region consisting of desiccated organic matter.

Figure 2. Left: Partially non-nacreous blister pearl showing significant surface-reaching cracks (blue arrow) and a distinct delineated step feature separating the light cream area from the adjacent black area (red arrow). Right: A columnar honeycomb-like calcite structure was observed at the edge of the step feature; field of view 14.40 mm. Photos by Karan Rajguru.
A closer look at the light cream, strongly iridescent section of the blister pearl with the distinctive platy structure looked more like “fingerprints,” distinctly separated by a delineated step feature from the adjacent black area. The black region was noticeably dull and matte and covered by a translucent layer revealing circular botryoidal surface spirals with a calcitic columnar pattern. Additionally, significant surface-reaching cracks were present in the translucent black area along the columnar structures (figure 2, left). Within the non-nacreous “cellular” structure, a layer had peeled off, accentuating the light cream calcitic step feature (figure 2, right).

Figure 3. Left: A real-time microradiograph image showing the internal structure of the blister pearl consisting of an organic-rich core surrounded by concentric growth arcs (red arrow) with parasite holes in the host shell (blue arrow). Right: Strong orangy red reaction under long-wave UV light, observed on the edge of the shell and part of the black area on the blister pearl. Photos by Lubna Sahani (left) and Gaurav Bera (right).
Real-time microradiography imaging of the blister pearl and its host shell revealed a distinct outline showing the point of attachment of the pearl to the shell. An organic-rich core with contrasting patchy light and dark gray areas occupied almost half of the pearl’s internal structure (figure 3, left). This was surrounded by concentric growth arcs, which are classic features of natural pearl structures, similar to those observed in known Pinctada radiata pearls from GIA’s research database. In addition, significant cracks extending from the pearl to the shell and parasite tubes forming a dendritic pattern in the host shell were seen when the pearl was X-rayed in other directions. The structure indicated a natural whole pearl that had attached itself to the host shell (“Natural shell blisters and blister pearls: What’s the difference?” GIA Research News, August 26, 2019).
Due to the limitations imposed by the size of the shell, it was not possible to collect chemical data on the pearl using energy-dispersive X-ray fluorescence spectrometry. However, both shell and pearl showed an inert reaction when exposed to X-ray fluorescence, indicative of its saltwater origin. An interesting reaction was observed under long-wave ultraviolet light. The edge of the shell and part of the black area on the pearl showed a strong orangy red fluorescence, while the inner part of the shell displayed a weak blue reaction (figure 3, right). The shell was inert under short-wave UV. Similar reactions linked to a type of porphyrin pigment have been observed in partially non-nacreous and nacreous pearls from the Pteria species (S. Karampelas, “Black non-nacreous natural pearls from Pteria species,” Journal of Gemmology, Vol. 35, No. 7, 2017, pp. 590–592). Raman spectroscopy using 514 nm and 814 nm laser excitation revealed peaks at 701/704 cm–1 and 1086 cm–1, indicative of aragonite. Due to high fluorescence, no calcitic peaks were observed in the non-nacreous area. Photoluminescence spectra collected from both the shell and the blister pearl revealed three broad peaks centered at 620, 650, and 680 nm, which are characteristic of some naturally colored pearls.
Formation of natural blister pearls in the wild has always been an interesting topic of research for gemological laboratories. The studied sample is certainly noteworthy due to its size, partially non-nacreous structure, and unique reaction under long-wave ultraviolet light. @chapter:14


Publication Year: - Title: 2017 US Holiday Jewelry Sales Rise, Reports Indicate Continued Economic Growth Abstract: A recent survey finds that jewelers remain a critical part of the jewelry buying process. Consumers who speak to a jeweler during the research process are also more likely to buy from a local store rather than online. Photo by GIA

Holiday jewelry sales in the U.S. increased 5.9% in 2017, according to a Mastercard-SpendingPulse survey, and outpaced spending in general, which increased 4.9%. The survey found that jewelry buying was running behind other retail categories until the week before Christmas when sales surged. Mastercard’s survey results are typically a bit higher than others.

A Centurion survey of primarily upscale jewelry retailers found that nearly 60% reported sales increases (one-third of those over 10%), but many noted that the gains came despite decreased customer traffic – fewer buyers were spending more money.

Signet Plc, the largest jewelry chain, turned in a disappointing season, however. Declining traffic at shopping malls and problems with its credit program resulted in a sub-par season: a 5.3% decline in its same store U.S. sales and an 8% decline overall.

Signet, the parent company to Kay Jewelers, Zales and Jared the Galleria of Jewelry, outsourced its credit card division amid allegations of improper practices that remain under investigation. Signet claims the allegations lack merit. Some 62% of the company’s sales are made on credit.

While retail sales continue to migrate to e-commerce outlets, jewelers remain a critical part of the jewelry buying process, according to a survey by Jewelers of America.

Conducted by Provoke Insights, the survey found that the jewelry purchase process is different from other high-priced luxury items: 64% of consumers who purchased jewelry visited a retail outlet to speak to a jeweler during the research process, a number that is 26% higher than other luxury items.

The study, which polled both consumers and retailers, also found that consumers who speak to a jeweler during the research process are also more likely to buy from a local store rather than online.
U.S. ECONOMY
Most economic forecasts predict the stock market and U.S. economy will continue its long growth cycle through 2018.

The Conference Board, a global, independent business membership and research association, forecasts that the unemployment rate will fall to 3.5% and GDP will grow 2.8% this year. The reason for the optimism is that economists see expansion widening into sectors that had been lagging behind the general recovery.

“The U.S. economy continues to fire on all cylinders with consumption, business investment and external trade all showing strength entering 2018,” the association reported. “Overall, expect 2018 to be a year where both growth and profits are plentiful. Spending growth should remain robust beyond the holiday season into 2018.”
DIAMONDS
The rough diamond market remained soft in 2017 as inventories accumulated some four million carats in the cutting centers between the beginning of 2016 to mid-2017.

De Beers sold an estimated $5.3 billion worth of rough diamonds in 2017, about 5% below 2016 levels of $5.6 billion. The company curtailed its allocations in the third quarter of the year because prices began to decline at the same time banks were reducing available credit to the industry.

Polished stocks in the cutting centers increased about two million carats (+12.7%) between early 2016 and mid-2017, as production outpaced demand.

Alrosa forecasts that 2018 will be “stable” with moderate growth compared to 2017. The Russian diamond producer said its sales declined 5% to $4.17 billion this past year because of increased demand for smaller, lower-cost diamonds.

The Letseng Mine in Lesotho, which had produced some of the world’s largest rough diamonds during the past decade, yielded its largest diamond yet, a 910 ct stone its owners claim is D color, type II. The crystal is the fifth largest diamond ever found.
CHALLENGES FOR DIAMOND INDUSTRY
While the economy seems robust, the diamond industry will continue to face challenges, according to a report from one of the industry’s top lenders, ABN Amro.

The bank’s report noted that synthetic diamonds will make ever-increasing inroads into the natural diamond industry, forcing substantial changes in both the rough and polished sectors. The report noted that production of gem quality synthetics totaled between 2.5 and 4.4 million carats in 2017, representing. 0.1% of all synthetic diamond production, with the balance destined for industrial use.

The bank maintained, however, that gem quality synthetics are more profitable than industrials, making it likely that some producers will convert some production to those better qualities. ABN Amro predicted that if gem quality production accounts for just 5% of all synthetics manufactured, it would exceed the total of all natural diamonds mined by 1.5 times.

The bank also noted that the increased production of synthetics, along with improvements in the process that will bring larger, better quality stones to the market at ever-cheaper prices, could present a fundamental challenge to natural diamond producers.

Natural rough diamonds remain a sellers’ market, lodged in the hands of relatively few producers, according to the ABN Amro report. As lower-priced synthetics assume a greater share of the market, however, competition will increase and prices for both classes of diamonds will fall, putting pressure on profits all the way around. Therefore, profitability will be more difficult and force producers of natural diamonds “into fundamental changes in their supply strategy.”

The laboratory-grown diamond producers have seized an advantage in their marketing strategy: emphasizing claims that laboratory-grown diamonds are more sustainable. Laboratory-grown diamond producers have been able to connect with the millennials by promoting themselves as high-tech, innovative and clean.

“The natural diamond producers are facing a challenge to improve the sentiment towards mined diamonds with that generation,” the report said.

In response, the Diamond Producers Association (DPA) has increased its marketing budget to spur diamond demand among younger consumers and to counter the messages from the synthetics producers.

The ABN Amro report also noted that diamond manufacturers will probably have to seek alternative funding from venture capital firms, from mining companies and even, possibly, crowd funding.

Finally, the report noted that it’s unlikely that diamonds as an investment vehicle will gain serious traction in the near term because valuation remains opaque. The possible exception is large diamonds or fancy color diamonds – where auction houses provide public price guidance. @chapter:27


Publication Year: 2019 Title: Book Review: Jewels & Jewelry Abstract: By Clare Phillips, softcover, 224 pp., illus., publ. by Thames and Hudson, New York, 2019, $40.00.

Jewels & Jewelry by Clare Phillips is a colorful depiction of the evolution of jewelry and accessories in Western civilization. The book is outlined in three parts and brings the reader on an educational journey using the pieces that are on display at the London’s Victoria and Albert Museum. Phillips’s writing—with accompanying photographs—reinforces that the jewelry industry is ever changing and influenced by popular culture.
Phillips starts out by discussing the common materials that will be found in the pieces, from metals to the gemstones and enamels that decorate them. From there, Phillips goes in chronological order, from the Middle Ages to today, showing how styles have changed. She describes how expeditions and conquerors returned to Europe with new materials and important gemstones from newly discovered sources, how the evolution of machinery allowed for mass production of jewelry pieces, and how the availability of goods was affected during the world wars due to restrictions on materials like platinum and certain gold. The final part discussed the manufacturing and distribution pieces in regards to the use of hallmarks and the design aspects of shops. Phillips mentions the importance of a jewelry’s history, due to the common practice of recycling metals and re-cutting and re-setting stones. Documentation of items (i.e., hallmarks and portraits) help to keep its history.
The high-quality photographs of the jewelry and accessories were carefully chosen to complement the passages. The evolution of gem cutting, from simple facets to round brilliants, is apparent in these pieces. Phillips also used paintings from the seventeenth through nineteenth centuries to show how people wore the jewelry and how styles have changed. For instance, she discusses the design aspect of Queen Victoria’s coronet in 1842 and then how it was restyled in the 1920s to be worn lower on the brow.
The book itself was quite easy to follow along for those with a basic jewelry background. The three sections succeeded in getting their concept across: materials, evolution of style, and distribution. The materials section gave just the right amount of information for the reader to understand what would be brought up later in the style section. Phillips brings in key players of the jewelry world, such as Fabergé and Cartier, but balances them out with lesser-known but equally important artists, such as Arthur and Georgie Gaskin and Alexander Calder. She also depicts the influencers who popularized jewelry styles: Monarchs of the seventeenth and eighteenth century, those involved in the post-war surrealism movements in the twentieth century, to celebrities such as Beyoncé in the twenty-first century.
When going through Jewels & Jewelry, keep in mind that its focus is on pieces from Western civilization pieces (i.e., the UK, Germany, and America). However, this is a great book to use to understand how goods and ideas are transferred from one country to the next. For instance, Phillips points out how the opening of the Japanese ports in the 1850s and the creation of the Indian Museum in 1801 that housed goods collected by the British East India Company introduced new concepts and inspired jewelers and artists alike.
If you are looking for a book that has a vast number of intricate pieces—from brooches to cigarette cases—and the history behind them, Jewels & Jewelry should be a top pick. @chapter:21


Publication Year: 2018 Title: Zoning In on Liddicoatite Exhibit Abstract: Figure 1. At the 64th annual Tucson Gem and Mineral Show, the GIA Museum hosted Zoning In on Liddicoatite in honor of Richard T. Liddicoat’s 100th birthday. Photo by McKenzie Santimer.
The calcium-rich lithium tourmaline liddicoatite was first recognized as a new mineral species in 1977. It was named by research staff at the Smithsonian Institution after GIA’s then-president, Richard T. Liddicoat (1918–2002). In honor of Mr. Liddicoat’s centennial birthday, the GIA Museum hosted an exhibit titled Zoning In on Liddicoatite at the Tucson Gem and Mineral Show, February 8–11. With highlights from Mr. Liddicoat’s career alongside crystals and polished crystal slices showing spectacular color zonation (figure 1), the exhibit was a fitting tribute to GIA’s own “Father of Modern Gemology.” @chapter:0


Publication Year: 1988 Title: Faceting Large Gemstones Abstract: The quest for the largest permeates all societies and disciplines. With the advent of new machinery and techniques, size records for faceted gemstones are falling constantly.  Currently, a 22,898-ct yellow topaz holds the record for weight and a 19,548-ct citrine holds the record for size. This article discusses some of the more important gemstone giants, and describes the specialized equipment and techniques developed to cut and polish them. @chapter:24


Publication Year: 2015 Title: Chrysocolla In Quartz Abstract: 52.96 ct and 19.16 ct chrysocolla in quartz, obtained from Rare Earth Mining Company at the AGTA show. Photos by Jian Xin (Jae) Liao.

              The Rare Earth Mining Company (Trumbull, Connecticut) booth at the AGTA show displayed a specialized inventory of unique and rare materials available as finished gemstones, mineral specimens, and fossils. Curt Heher, Rare Earth’s president of sales, reported more than 300 companies placing orders in finished stones alone: “We enjoyed our biggest Tucson show in 40 years.”

We obtained two cabochons of blue-spotted clear and near-colorless quartz, as seen above, that were reminiscent of “K2 stone” or “Raindrop azurite” seen in previous years (Spring 2012 GNI, pp. 55–56). Heher’s father bought the rough, which was crystallized around blue stalactites, at auction in the 1980s. It remained in storage until recently. The material was reportedly mined in Globe, Arizona, in the 1970s.

Gemological examination of the 19.16 and 52.96 ct cabochons revealed an RI of 1.54 to 1.55 in most areas, but approximately 1.5 in the blue area, and a 1.46 spot reading in transparent areas. Specific gravity ranged from 2.36 to 2.47. The fluorescence reaction to long-wave UV was weak white in fractures and the transparent areas. Raman analysis confirmed that the blue material was chrysocolla, the transparent to whitish areas were quartz, and the transparent cryptocrystalline areas were chalcedony. Raman analysis also indicated the presence of a hardened glassy polymer (polymethyl methacrylate). FTIR also confirmed the polymer, corroborating the stabilization that Heher indicated was needed to prevent crumbling or fracturing during the cutting and polishing process. The treatment conclusion on a GIA report would be “impregnated” or possibly “composite” if the polymer occupied significant volume or surface area.

Chrysocolla in quartz is not uncommon, but it is rare to see such defined stalactites resulting in a distinct orbicular pattern. This material often remains as mineral specimens rather than being cut for jewelry purposes. @chapter:13


Publication Year: 2019 Title: Johnkoivulaite: A New Gem Mineral Abstract: Figure 1. This 1.16 ct crystal of the new mineral johnkoivulaite was reportedly discovered in the legendary Mogok Valley of Myanmar in the Pein Pyit mining area. Photo by Robert Weldon/GIA.

A new mineral, johnkoivulaite, has been named in honor of John Koivula, a renowned microscopist and preeminent researcher at GIA for more than 40 years. In collaboration with scientists from the California Institute of Technology, Dr. Kyaw Thu of Macle Gem Trade Laboratory, and Nay Myo, a gem dealer from Mogok, GIA researchers described johnkoivulaite, which the International Mineralogical Association (IMA) formally accepted as a new mineral species on September 6, 2019.
The world’s first specimen of johnkoivulaite was reportedly uncovered from the Pein Pyit mining area of Mogok in Myanmar. It subsequently passed through the hands of Nay Myo, a local gem dealer. When the 1.16 ct stone (figure 1) could not be identified, Nay Myo suspected he had encountered a new mineral and had the sample sent to GIA for identification. When the researchers first examined the sample and realized its unique gemological properties, GIA made arrangements to purchase the unusual stone from Nay Myo so that additional advanced testing could be performed and the sample could be deposited in the GIA museum. Once the type specimen was housed in the museum (one of IMA’s requirements for describing a new mineral), the team was able to submit a new mineral proposal. According to IMA guidelines, a new mineral can be named in recognition of a person’s significant scientific contributions to the field of mineralogy. This one was named in honor of John Koivula’s lifelong efforts to advance the sciences of mineralogy and gemology.
Single-crystal X-ray diffraction (XRD) analysis was performed in collaboration with researchers at the California Institute of Technology and indicated a hexagonal crystal structure that was very similar to beryl and other members of the beryl group such as pezzottaite. Chemical analysis by LA-ICP-MS and EPMA identified enrichment in cesium, boron, and magnesium and confirmed johnkoivulaite’s membership in the beryl family, with its ideal end-member formula as Cs(Be2B)Mg2Si6O18. Standard gemological testing gave a refractive index of 1.608, with a birefringence too low to accurately measure, a specific gravity of 3.01, a hardness of 7½, a conchoidal fracture, vitreous luster, and no reaction to long-wave or short-wave UV. Especially notable is johnkoivulaite’s strong pleochroism from deep violet to nearly colorless when observed with polarized light (figure 2).

Figure 2. Johnkoivulaite shows strong pleochroism, going from near-colorless (left) to violet (right) when examined with polarized light. Photomicrographs by Nathan Renfro; field of view 10.05 mm.

Figure 3. The new mineral johnkoivulaite is named after renowned gemologist John Koivula, best known for his contributions to inclusion research and photomicrography. Photo by Kevin Schumacher.
John I. Koivula (figure 3) developed an interest in minerals and particularly their inclusions during childhood, when he found a quartz crystal with pyrite inclusions in North Bend, Washington. From there, Koivula earned degrees in geology and chemistry before working as an exploration geologist. In the 1970s, his career changed direction when a friend suggested the Graduate Gemologist program at GIA. He joined GIA in 1976 and began publishing gemological articles and short notes while refining his photomicrography techniques. In 1986, he co-authored with Edward J. Gübelin the immensely popular Photoatlas of Inclusions in Gemstones, which was followed by two additional volumes. Koivula also wrote The Microworld of Diamonds  and co-authored Geologica with Robert Coenraads. Other highlights of his career include winning first place in Nikon’s Small World Photomicrography competition in 1984, receiving the AGS’s Robert M. Shipley Award in 1996, and being named one of JCK magazine’s 64 Most Influential People in the Jewelry Industry in the 20th Century. In 2002, he was awarded the AGA’s Antonio C. Bonanno Award for Excellence in Gemology. Mr. Koivula also received GIA’s Richard T. Liddicoat Award for Distinguished Achievement in 2009 for his contributions to gemology.
After more than 40 years in the industry, Mr. Koivula still regularly contributes to gem and mineral research and is now a contributing editor for G&G’s Micro-World column.
The discovery of a new mineral is a rare and exciting occasion for the gemological community. It is a special honor for the authors to be able to name this mineral after such a prominent and well-deserving gemologist. @chapter:3


Publication Year: 2023 Title: Rare Natural Bicolor Diamond Abstract: Figure 1. This 0.63 ct tapered baguette-cut diamond showed two major color zones. Photo by Adriana Robinson.
A 0.63 ct bicolor diamond was submitted to GIA at the 2023 Tucson gem show for scientific examination. Previously submitted to GIA in 2008 for a colored diamond grading report, this tapered baguette-cut natural diamond had two major color zones: Fancy Dark orangy brown and Fancy Dark brown greenish yellow (figure 1). The brown greenish yellow zone had chameleon properties, including a temporary color change upon heating or when left in darkness for an extended period of time (possibly days).  Visible narrow bands with darker color were observed within the brown greenish yellow zone (figure 1). Fourier-transform infrared spectra collected from the two color zones indicated that both were type Ia with comparable nitrogen concentrations. No amber centers or carbon dioxide absorption were detected in either color zone.
Bicolor diamonds are very uncommon, and the colors likely result from a combination of lattice defects. The major causes for yellow coloration in diamond include N3 centers, C centers, H3 centers, and the 480 nm absorption band (C.M. Breeding et al., “Naturally colored yellow and orange gem diamonds: The nitrogen factor,” Summer 2020 G&G, pp. 194–219), whereas brown coloration is typically associated with vacancy clusters produced during plastic deformation (D. Fisher, “Brown diamonds and high pressure high temperature treatment,” Lithos, Vol. 112, Supplement 2, 2009, pp. 619–624). It has been reported that diamonds rich in carbon dioxide might also have a brown color (T. Hainschwang et al., “HPHT treatment of CO2 containing and CO2-related brown diamonds,” Diamond and Related Materials, Vol. 17, 2008, pp. 340–351). Ultraviolet/visible/near-infrared spectra collected separately from the two color zones to determine their color origins indicated that both color zones contained the 480 nm absorption band. In addition to this 480 nm absorption band, the brown color zone also showed enhanced absorption extending from the near-infrared region toward the UV region of the spectrum.

Figure 2. Alternating blue and greenish yellow fluorescence zones were observed with deep-UV excitation. This fluorescence pattern is typical for diamonds colored by the 480 nm visible absorption band. Image by Stephanie Shaw.
Diamonds colored by the 480 nm absorption band generally have multiple growth zones with distinct fluorescence colors excited by deep UV (<230 nm), due to their complex multi-stage growth under changing conditions in the earth’s mantle (Breeding et al., 2020). This bicolor diamond had alternating blue and greenish yellow fluorescence zones (figure 2), similar to the fluorescence patterns in other diamonds with the 480 nm absorption band. The fluorescence zones did not correlate with the major color zoning (i.e., orangy brown and brown greenish yellow) in this diamond. However, the greenish yellow fluorescence bands (figure 2) appeared to correspond to the narrow bands with darker color in the brown greenish yellow color zone (figure 1).

Figure 3. Multiple orange inclusions were observed in this bicolor diamond. The largest was identified as pyrope-almandine-grossular garnet. Photomicrograph by Mei Yan Lai; field of view 1.76 mm.
A cluster of orange mineral inclusions was observed beneath the table facet, where the largest inclusion measured 180 μm in maximum dimension (figure 3). The Raman spectrum of the largest inclusion showed the characteristic peaks of pyrope-almandine-grossular garnet, (Mg,Fe,Ca)3Al2(SiO4)3, at 358, 558, and 917 cm–1 (e.g., E.M. Smith et al., “Raman identification of inclusions in diamond,” Reviews in Mineralogy and Geochemistry, Vol. 88, 2022, pp. 451–473), indicating the diamond was associated with eclogite host rocks having pyrope-almandine-grossular garnet as a major constituent mineral.
This unique bicolor diamond exhibiting two distinctly different colors demonstrates the variety possible within the natural world. @chapter:11


Publication Year: 2022 Title: GSA 2022 Annual Meeting Abstract: Figure 1. GSA 2022 oral and poster presenters. Left to right: Elina Myagkaya, Shiyun Jin, Che Shen, Stephanie Persaud, Roy Bassoo, Rhiana Henry, Alexander Goodsuhm, Rachelle Turnier, Yusuke Katsurada, Mei Yan Lai, Matthew Hardman, Christopher Breeding, Evan Smith, and Peter Heaney. Photo by Robert Weldon.
The Geological Society of America (GSA) held its annual meeting October 9–12 in Denver, Colorado. GIA’s tenth technical session, entitled “Gemological Research in the Twenty-First Century—Gem Materials and Localities,” featured twelve oral presentations and five posters (figure 1), covering broad topics including diamond, sapphire, tourmaline, sunstone, nephrite, and other gem materials.
Colored Gemstones and Other Subjects. The session started with recent research on colored gemstones. Dr. Peter Heaney (Pennsylvania State University, State College) opened with a keynote presentation addressing the structural coloration in colored gemstones that is produced by micro- or nano-structures. This structural coloration results from the interference of nanoparticle inclusions with light waves, including film interference, diffraction grating, scattering, and photonic crystals. Nanoparticles were characterized by a variety of techniques, including scanning electron microscopy (SEM), focused ion beam (FIB), transmission electron microscopy (TEM), and atomic force microscopy (AFM). Dr. Heaney summarized his group’s state-of-the-art research on iridescent gemstones, including three-dimensional photonic arrays of hematite (Fe2O3) nanoneedles, quasi-periodic void layers in goethite (FeOOH), blazed gratings of Brazil twinning in iridescent quartz, and hierarchical oscillation layers in iris agate. Continuing with the topic of structural colorization, Dr. Shiyun Jin (GIA, Carlsbad) investigated the cause of special colors (green, red, and watermelon) and the optical effects of pleochroism in Oregon sunstone. The absorption and scattering power of copper nanoparticles in sunstone was tested with experimental absorption/scattering spectra and modeling based on Maxwell’s equations. By comparing his experimental results and simulations, Dr. Jin concluded that the metallic copper nanoparticles in Oregon sunstone absorb and scatter incident light differently with respect to light polarization, thus yielding various color effects. Che Shen (Munsell Color Science Laboratory, Rochester Institute of Technology) studied the color change in sapphire caused by varying the amounts of six major chromophores (V3+, Cr3+, Fe3+, Fe2+-Ti4+, h-Cr3+, and h-Fe3+). Using chromatic adaptation transformation (CAT), the color of sapphire under daylight and incandescent light were modeled by combining various chromophores. Shen concluded that blue/purple sapphire is caused by Fe2+-Ti4+ and Cr3+, green/reddish brown sapphire by Fe2+-Ti4+ and Fe3+, and pink/purplish brown sapphire by Fe2+-Ti4+, Cr3+, and Fe3+.

Figure 2. Aaron Palke presented the various types of melt inclusions in Montana’s secondary sapphire. James Shigley (seated) moderated the session. Photo by Robert Weldon.
Other oral presentations focused on sapphire formation. Dr. Aaron Palke (GIA, Carlsbad) investigated the multiple types of melt inclusions in Montana’s secondary sapphire, especially silica-rich felsic, sulfide, and polycrystalline melts (figure 2). The presence of multiple types of melt inclusions indicates that these sapphires are of magmatic origin. Further research on Montana sapphire by Alexander Goodsuhm (GIA, Carlsbad) constrained the formation conditions for Montana sapphire using zircon concentrations in rutile inclusions. Zircon concentrations in rutile inclusions ranged from 194 to 1340 ppm using inductively coupled plasma–mass spectrometry. Missouri River sapphire was suggested to form at a higher temperature (~750°C) than Rock Creek sapphire (~660°C). Dr. Rachelle Turnier (GIA, Carlsbad) studied sapphire from Myanmar, Madagascar, and Sri Lanka, pairing photoluminescence (PL) spectra and trace element contents. Dr. Turnier observed that Cr3+ in sapphire is an efficient luminophore with intense red luminescence emission. Chromium in the corundum lattice can overcome high iron concentration and still cause intense luminescence. For example, 3 ppmw Cr3+ and 2500 ppmw Fe3+ can still yield luminescence of 1,000,000 counts/s/mW.
Other colored gemstone studies included beryl (oral), tourmaline (oral), and nephrite (poster). Dr. Rhiana Henry (Earth, Ocean and Atmospheric Sciences Department, University of British Columbia, Vancouver) investigated structural changes in response to chemical composition variation in beryl (Be3Al2Si6O18). Beryl’s crystal structure was analyzed using single-crystal X-ray diffraction (XRD), and chemical composition was acquired via electron microprobe analysis (EPMA). She concluded that beryl’s crystal structure could be calculated using the average ionic radii of the measured cations at the aluminum site (octahedron site) and the beryllium site (one of the tetrahedron sites). Dr. Yusuke Katsurada (GIA, Tokyo) investigated the dominant chromophores (Fe2+ and Cu2+) in cuprian Paraíba tourmaline. Oriented wafers were prepared to collect both o-ray and e-ray ultraviolet/visible/near-infrared (UV-Vis-NIR) absorption spectra. Copper and iron concentrations were measured with laser ablation–inductively coupled plasma–mass spectrometry. This study contributes to the simulation of unpolarized UV-Vis-NIR spectrum and the approximation of copper and iron concentrations in cuprian tourmaline. Ping Li (Tongji University, Shanghai) demonstrated nephrite’s microstructure as an indicator of origin. Nephrite microstructure, including grain size and mineral aggregation, were observed under the petrographic microscope. Nephrites from Xiaomeiling, Maxianshan, and Longxi in China underwent different extents of tectonism and metasomatism.
In recent years, GIA’s Research and Development department has broadened its areas of interest, which was demonstrated in two other presentations. Dr. Matthew Hardman (GIA, Carlsbad) investigated the capability of machine learning to classify treated/untreated and synthetic/natural gemstones. More than 3,000 PL spectra of diamonds and 500 sets of trace element data of pearls were studied using the Boruta statistical algorithm. This approach identified PL peaks at 67.6, 503.2, 524.3, and 575.0 nm as important in identifying the treatment of CVD lab-grown diamond. Using machine learning, Dr. Hardman confirmed that manganese concentration is significant in identifying seawater or freshwater origin in pearls. Dr. Sona Taijiryan (GIA, Carlsbad) presented a poster on the main gem trading routes of the early modern period, from 1500 to 1800 CE. By translating an eighteenth-century manuscript from an Armenian gem merchant in India, Dr. Tajiryan demonstrated the East-West trade routes for the most popular gems in the first half of that century, including Indian diamonds, Southeast Asian rubies and spinels, Colombian emeralds, Sri Lankan pearls, and Mediterranean corals.
Diamonds. Dr. Evan Smith (GIA, New York) investigated a 910 ct type IIa diamond from Lesotho to indicate its formation in the mantle. This type of large and highly pure diamond is commonly known as CLIPPIR (Cullinan-like, large, inclusion-poor, pure, irregular) diamond. Inclusions such as cohenite (Fe3C), troilite (FeS), and metallic Fe-Ni-C-S melt were identified using synchrotron X-ray diffraction at Argonne National Laboratory. The geochemistry of these inclusions confirmed a sublithospheric origin of the host diamond and provided evidence that during the diamond’s formation, subduction of basaltic ocean crust to the lower mantle was occurring. Dr. Mei Yan Lai (GIA, Carlsbad) shared her recent doctoral research completed at the University of Alberta, which investigated lithospheric mantle composition and volatile recycling in the West African Craton. Inclusion mineralogy, major/trace elemental composition, and carbon/nitrogen host isotopic analyses for 105 diamonds from the Koidu mine in Sierra Leone were systematically analyzed. Dr. Lai indicated two significant and distinct episodes of eclogitic diamond formation in Koidu diamonds: cores precipitated from crustal melts and rims formed from mantle-derived melts.
Other presentations examined diamond in sedimentary systems. In alluvial environments, alpha radiation can cause a green or brown surface color. Dr. Christopher M. Breeding (GIA, Carlsbad) reported on his recent study of a rare pink stain in a natural type Ib Fancy brownish yellow diamond, a feature also caused by radiation damage. PL spectroscopy suggested that high concentrations of nitrogen-vacancy (NV–) defects caused the pink color. It was suspected to have originated as a green diamond that turned pink as a result of higher temperature burial. Also, Dr. Roy Bassoo (GIA, Carlsbad) reported on various thermal annealing experiments on natural colorless diamonds to imitate diamond residence in a natural sedimentary system. Nitrogen content and aggregation, defect concentration, and luminescence color response upon heating were studied using Fourier-transform infrared (FTIR) spectroscopy, PL spectroscopy, and optical UV luminescence, respectively. Dr. Bassoo concluded that diamonds in a sedimentary system do not change their bodycolor, but such a system can influence defect-related luminescence.
GIA poster sessions highlighted three interesting colored diamond projects. First, Sarah Arden, Abadie Ludlam, and Elina Myagkaya (GIA, New York) presented their study on etch channels in a 3.17 ct pink type IIa diamond. A profusion of meandering (“worming”) channels of various lengths embedded in this pink diamond were observed with micro X-ray computed tomography (CT). High strain was observed under the polariscope, and GR1 defects were mapped as clusters around etch channels using PL. The authors hypothesized two possible formation mechanisms for the etch channels’ formation: (1) a type of line defect causing localized strain that is more vulnerable to dissolution and/or (2) Rose channels caused by micro-twinning and subsequently etched by mantle fluids. Skyelar Caplan (GIA, New York) reported a new color center (525 nm) as the cause of type Ia Fancy pink diamond. The 525 nm band together with an H-related 835 nm broad band caused a transmission for yellow and green light (610–660 nm) and resulted in a pink color. The 525 nm band observed in the UV-Vis absorption spectrum was related to high nickel content. Stephanie Persaud (GIA, New York) investigated two types of color-changing diamonds, chameleon and cryogenic, using spectroscopic analysis. Chameleon diamond changes from grayish green to orangy yellow upon heating, while cryogenic diamond changes from dark gray to light yellow when cooled to freezing temperatures. The cause of color change upon heating/cooling was attributed to changes in energy within the electron band gap.

Figure 3. The GIA booth attracted GSA attendees from all over the world. In the foreground, Nathan Renfro speaks with a visitor. Photo by Cathy Jonathan.
In addition to the research talks and posters, GIA’s booth in the exhibition hall also attracted many visitors. Robert Weldon (GIA, Carlsbad) hosted a demonstration of the use of light and camera settings for gemstone photography. He shared the stories and knowledge behind his photographs of the Hope diamond, the Dom Pedro aquamarine, and other notable gems. Nathan Renfro (GIA, Carlsbad) demonstrated techniques for inclusion photomicrography (figure 3) using different types of light sources.
An evening reception jointly hosted by GIA and the Mineralogical Society of America was held on October 11. The event provided gemologists and mineralogists with a great opportunity to exchange ideas and facilitate collaboration. In another GSA technical session, Dr. James Shigley shared GIA research opportunities with early-career mineralogists and crystallographers. Overall, the 2022 GSA meeting attracted strong attendance and notable interest in the gemology technical sessions and exhibits. We look forward to the 2023 GSA meeting, scheduled for October 15–18 in Pittsburgh, Pennsylvania. @chapter:6


Publication Year: - Title: Retail Jewelry Sales Up in US, But Wage Gains Drag Abstract: The 1,109 carat gem quality, Type IIa, Lesedi la Rona diamond, which originated from Lucara's Karowe Mine in Botswana, is the world's second largest gem quality diamond ever recovered. It recently sold to Laurence Graff for $53 million. Photo by Lucian Coman/© Lucara Diamond.

The U.S. Department of Commerce reports that retail jewelry and watch sales from all outlets have been running about 5.6% ahead of last year, with August significantly higher at 6.8%.
The National Retail Federation believes the year will finish strongly with sales increases of all merchandise up 3.2% to 3.8%. Employment numbers have been good but wages still lag, limiting the disposable income available for consumer products. This has been a drag on retail sales all year.
De Beers October cycle (sight) sales were $370 million, the lowest sight in nearly a decade. This was also well below September’s total of $505 million, which was well below earlier cycle sales.
In addition, Alrosa, the world’s largest diamond producer by volume (but well behind De Beers by value,) sold $305.8 million worth of rough diamonds in September. The volume was similar to the previous month, but the value was higher because the company sold a number of “specials” – diamonds larger than 10.8 cts.
After starting this year with several large allocations, the company reduced its sales volumes during the second half of the year. Rough sales have totaled $3.29 billion for the first nine months of 2017, similar to last year.
The short term reason for the reduced sales by De Beers and Alrosa is the Indian holiday of Diwali that began Oct. 19, which is about 10 days earlier than usual. Typically, diamond firms close their operations for two weeks during and after the holiday, but diamond manufacturers often delay their return to work if orders have been slow and they have sufficient inventory.
For the longer term, inventories of polished have been mounting – rising by an estimated 30% to 35% this year – while credit lines shrink and polished prices soften. The $50 million-plus bankruptcy of Exelco, an Antwerp diamond company, is the latest incident in diamond industry banks pulling back from the industry.
Analysts believe more bankruptcies may follow. The key worry, of course, is that these companies have tens of millions of dollars in outstanding trade debts and a default could send other companies into bankruptcy.
THE BIG DIAMOND
The 1,109 ct Lesedi la Rona went to London mega-jeweler Laurence Graff for $53 million, or $47,800 per carat, which is significantly less than its owner, Lucara Mining, wanted for the stone. It is the second largest gem-quality rough diamond ever found.
At this price, the stone will be economical to cut – the polished will bring about $100,000 per carat, assuming a 40% to 50% yield. Very large D-E color, flawless diamonds have been selling for $140,000 to $180,000 per carat at auctions.
Lucara tried to sell the diamond at an auction in Sotheby’s London salesroom, but bidding fell way short of the $70 to $75 million the company was reportedly seeking. (Sotheby’s 12.5% buyers’ commission plus VAT of 5% to 15% would have pushed the price past $80 million). This made the diamond uneconomical to cut, pushing the price of the resulting polished past $150,000 per carat. @chapter:30


Publication Year: 2023 Title: Lab-Grown Diamonds: A Popular Trend Among Modern Consumers Abstract: The lab-grown diamond market, or LGD, globally in the year 2022 was valued at 23,898.60 million USD. It is expected to grow at an average rate of approximately 8.64% from 2022 to 2028. Lab-grown diamonds are created in laboratories, possessing durability and brilliance similar to natural diamonds but are produced in a shorter timeframe, resulting in relatively lower prices.
The market for lab-grown diamonds has expanded significantly in recent years and gained traction as an alternative to natural diamonds. Factors driving this popularity among new-generation consumers include affordability, environmental friendliness, and ethical considerations. This has propelled lab-grown diamonds into a highly favored category in the current jewelry market.
However, the robust expansion of lab-grown diamonds has directly impacted the market for natural diamonds, leading to clear price adjustments downwards. Data from Tenoris, a market research company, collected over three years in the United States, shows a substantial increase in the sale of lab-grown diamonds, particularly with a notable surge of 22.9% in the first two months of 2022 compared to an 8.5% growth in 2020.
Moreover, based on calculations and trends, lab-grown diamonds are anticipated to constitute up to 50% of the retail diamond market in the United States by May 2025. Major retailers like Signet Jewelers and Pandora have embraced lab-grown diamonds to cater to the preferences of new-generation consumers, leveraging their price competitiveness. Conversely, traditional diamond traders such as De Beers have recognized the growth potential in the lab-grown diamond market and introduced new brands like 'Lightbox' to capitalize on this trend.
Economic slowdowns in the United States have prompted consumers to prioritize price and value in their purchases, influencing the jewelry market significantly. Consumers are increasingly opting for lab-grown diamonds as gifts, especially during occasions like Valentine's Day, due to their affordability and improved quality compared to previous years.
In summary, the lab-grown diamond market's growth has impacted the natural diamond market directly by offering a more affordable and attractive alternative. This shift has prompted significant price adjustments and changes in consumer behavior, fostering new opportunities for Thailand's soft-colored gemstones alongside the growing lab-grown diamond trend. @chapter:30


Publication Year: 2008 Title: Aquamarine, Maxixe-Type Beryl, and Hydrothermal Synthetic Blue Beryl: Analysis and Identification Abstract: Aquamarine, Maxixe-type (irradiated) beryl, and two types of hydrothermally grown synthetic blue beryl currently available in the marketplace were investigated by classical gemological methods, chemical analysis, and UV-Vis-NIR and mid-IR spectroscopy. These materials may be conclusively identified by a combination of these techniques. The Maxixe-type beryl (like natural-color Maxixe beryls) is distinguishable by its unusual dichroism, green UV fluorescence (when present), Fe-free chemical composition, and distinctive UV-Vis-NIR spectrum. The hydrothermal synthetic blue beryls can be discriminated from their natural counterparts on the basis of microscopic features, chemical composition, and visible and infrared spectroscopic features. @chapter:9


Publication Year: - Title: Chipping Away at the 1,109 ct Lesedi La Rona: 60 D Flawless Diamonds Abstract: Left top, the 1,109 ct Lesedi La Rona minus the portion to produce the first polished stones. In all, Graff expects 60-plus D fl diamonds from the rough. The largest portion of the rough is still under study and the size and shape of the signature diamond remains undetermined. Photo courtesy of Graff.

London jeweler Laurence Graff unveiled the first diamonds polished from the 1109 ct Lesedi La Rona, which is expected to yield some 60 stones ranging from under one carat to over 100 cts, according to the company.

Second only to the 3,106 ct Cullinan, the diamond was found in the Kerowe mine, Botswana, in November 2015 and put up for public auction in 2016, where it failed to achieve its reserve price of about $70 million. Graff purchased the diamond for $53 million in September 2017.

Graff’s diamond cutters carefully analyzed the diamond for several months before making the first cut. The company did not detail the exact carat weights of the finished diamonds, but the website noted that “Graff designers have envisaged a collection of striking rings, earrings and pendants that celebrate the extraordinary provenance of the Lesedi La Rona diamonds at their heart.” All will be graded and inscribed with the Lesedi La Rona provenance by GIA.

The largest portion of the rough is still being worked on, though no estimate of how large or how many more diamonds will be made from the remaining portion have been announced.
ARGYLE TENDER
The 2019 Argyle Pink Diamond Tender saw a 2.28 ct Fancy Vivid purplish red achieve the highest price for any diamond in the 34-year history of the company’s colored diamond auctions. The diamond, named the Argyle Muse, was cut from a 7.39 ct piece of rough. The buyer and the price of the diamond were not disclosed. The other highlight of the tender, a 3.14 Fancy Vivid pink, went to Glajz THG of Singapore for an undisclosed price.

All of the 63 diamonds in the tender, which weighed a total of 51 carats, were graded by GIA.
DIAMOND MARKET
The credit squeeze, high operating costs and financial problems caused a significant drop in the number of diamond manufacturing operations worldwide.

Ronnie VanderLinden, president of the International Diamond Manufacturers Association, reported at its semi-annual meeting that the decline was “changing the landscape of diamond manufacturing,” according to press reports.

VanderLinden said the decline has affected most manufacturing centers, including Africa where many operations that had begun to increase employment and skills in source countries have faltered. Many of these operations were part of large Indian firms that have experienced financial difficulties in recent years because of lagging polished prices and severe credit cutbacks. In China, he noted, diamond manufacturing employment is down to about 5,000 from a high of 40,000.

He said the health of the diamond industry depends greatly on the health of diamond manufacturing.
ALROSA
A sharp fall in the value of the Indian rupee coupled with on-going credit shortages caused Alrosa, Russia’s diamond mining and sales operation, to sharply cut its sales of small diamonds for its October allocation. Sales that month were $234 million, a 28% decline from the same period last year.

The company said its production and total yearly rough sales will be down by about 9% to 37 or 38 million carats. Last year it sold 39.6 million carats.
CONSUMERS
Consumer confidence registered a slight increase in October, despite wild fluctuations in the world stock markets, according to the Conference Board monthly survey.

“Consumer confidence increased in October, following a modest gain in September, and remains at levels last seen in the fall of 2000,” said Lynn Franco, senior director of economic indicators at the Conference Board. “Consumers’ assessment of present-day conditions remains quite positive, primarily due to strong employment growth. The Expectations Index posted another gain in October, suggesting that consumers do not foresee the economy losing steam anytime soon. Rather, they expect the strong pace of growth to carry over into early 2019.” @chapter:38