# Publication Year: -
# Title: Polki Diamonds: A ‘New’ Fashion Statement from Mogul India
# Abstract: This three-strand bracelet by Sally Agarwal, London, shows how old-style polki diamonds work well in new jewelry designs. The bracelet contains 87 polki cut diamonds, total weight approximately 11.85 ct. set into 18K gold. Photo courtesy Sally Agarwal

Celebrity jewelry designer Jade Jagger sent many jewelers to their glossaries when she introduced a line of jewels featuring “polki” diamonds a few years ago.

Polki diamonds are, in fact, one of the oldest forms of cut diamonds, originating in India long before Western cutting methods were seen there. They often retain their original rough form and have an unfaceted, polished surface. Although they have remained in use in traditional Indian jewelry designs − mainly fashioned for wedding pieces − Western designers like Jagger, who is based in London, and others have begun to incorporate these classic gems into their pieces.

The appeal, according to another London-based designer Sally Agarwal, “is that they generally are cut to follow the original rough stone so no two are alike and they impart a distinctiveness that makes each piece unique.” There’s another reason she is drawn to these diamonds. “They are very flattering to the wearer because the light they give off is much softer compared to the sparkle of modern cuts.”

A polki cut diamond of approximately 0.5 carats bezel set into a gold and enameled ring by Jade Jagger. Many polki cut diamonds are highly included, which adds to their distinctive look. Photo courtesy of Jade Jagger Studio, London
Many of Jagger’s pieces mix polki diamonds with lapis or sapphire. Agarwal’s pieces blend a traditional Mogul jewel look with floral and geometric motifs.

India is the original source of diamonds, with historical accounts of finding the gems dating back 3,000 years. It was the first major culture to value and wear diamonds and many of the world’s legendary diamonds were unearthed there – the Hope Diamond, Koh-i-Noor, Wittelsbach-Graff, Sancy and Regent are the best known.

British jewelry historian Jack Ogden noted that one of the earliest accounts of gem cutting in India was made by the noted Persian scholar al Biruni, who visited India about 1020 CE and wrote that cutters used emery, a dark granular mineral usually composed of powdered corundum, manganite and possibly spinel or hematite, “for cutting, filing and polishing stones.” Of course emery (ranging 7 to 9 on the Mohs scale), could not facet diamonds (10 on the Mohs scale), so cutters used it to polish the surface of the rough stones.

Ogden wrote that it is not entirely clear whether ancient and medieval Indian cutters knew to use diamond powder for cutting, but noted that as much as 700 years later many Indian cutters were still using emery mixed with oil, so cutting techniques had apparently changed little as well. Most diamonds and gemstones were worked on a stone wheel, set vertically. The polisher pushed and pulled on a bow attached to the wheel, turning it back and forth instead of continuously rotating, while holding the stone to be polished with his other hand.

Portuguese explorer Vasco da Gama is usually given credit for leading the first European expedition to establish regular contact with India in 1490. When John Baptiste Tavernier arrived there 200 years later on his famous voyage, he found a flourishing gem trade, including diamonds. By then, some Indian cutters had learned how to cleave diamonds and apply shallow facets using emery and diamond powder on their polishing wheels, according to Tavernier. He called these Mogul cuts, which generally took the form of near-rectangles with beveled edges, lozenge or uneven oval and pear shapes. The latter two had small, angled facets, according to Ogden. A slight adjustment fashioned a faceted crown on top of a flat base and were called polki cuts.

The following centuries saw a growing trade between the West and India; the royalty who ruled the country’s various principalities became regular patrons of the major European master jewelers. The royals purchased many diamonds cut and polished in Europe, which were the forerunners of modern brilliant cuts.

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Indian and Western cutters had a fundamentally different approach, noted Al Gilbertson, GIA’s manager of cut research in Carlsbad, California.

“Mogul cuts are without any particular facet arrangement and have an irregular and asymmetrical form as the cutter was striving for the maximum size possible, but without what they deemed to be flaws,” he said. “Early European styles wanted to follow the design of an octahedron crystal and then slowly moved towards reflecting light back to the viewer as early as the 15th century. This lead to having a large top facet (the table) and various arrangements of facets on the pavilion designed to reflect light back to the observer.”

By the early 19th century, European cutting techniques were adopted by Indian cutters. They remained loyal to cutting diamonds that stayed close to their natural forms, however, because after at least a thousand years, these traditional cutting techniques had become ingrained into the style of Indian jewels. Today, polki is the name applied to a variety of traditional Indian cuts.

“Polki diamonds are still used in most wedding jewels which are still very traditional,” said Siddhartha Sacheti, of Jaipur Gems, a Mumbai-based retailer. “Usually they are backed with silver foil and enameled at the back in the manner of most traditional Indian jewelry.”

Sacheti also explained that while the look remains similar to diamonds cut in centuries past, manufacturing polki diamonds is as up to date as their round brilliant counterparts. “They are all laser-sawn into slices and then polished or lightly faceted by machine,” said Sacheti.

Because they are usually much less expensive than round brilliants or modern fancies, diamond manufacturers use highly included or cloudy rough that still has good color. “The included stones would have a very low yield if they were made into modern cuts,” Sacheti said.

This Mogul-style necklace, by Amrapalli Jewels in Jaipur, features a large polki cut diamond set inside a carved emerald, surrounded by polki cut diamonds. The necklace also features two cabochon sapphires, cultured South Sea pearls and polki cut diamonds. Photo by Eric Welch/GIA
The lower per-carat prices don’t always translate into lower prices at the shop, said Agarwal, who markets her jewels though her own site, boutiques in London and Mumbai, and luxury websites.

“They can be challenging to work with. First, I often have to wait until I find enough stones that will compliment one another in color and shape,” she said. “Second, there are no pre-manufactured settings. Everything has to be done by hand and it is not easy to find people skilled in that kind of work.”

Contemporary polki diamond jewelry is trending back to its roots. Sacheti has begun to make contemporary-looking polki jewels because millennial buyers in India are “looking both East and West.” @chapter:28 @chapter:2 @chapter:28


# Publication Year: 2017
# Title: Diamond with Concentric Inclusions
# Abstract: This 2.34 ct Fancy Intense yellow-green diamond (left) contains abundant inclusions that outline concentric octahedral growth layers. Through the table, the layers resemble nested rhombuses (center, field of view 3.54 mm). The inclusion shapes appear to be controlled by the layering, as seen through the pavilion (right, field of view 1.99 mm). Photos by Evan Smith.
As a diamond grows, layer by layer, it may incorporate small pieces of the surrounding mantle rocks as mineral inclusions. The three-dimensional arrangement of inclusions in most diamonds has the appearance of being somewhat random, with no discernible pattern. However, GIA’s New York laboratory recently examined a noteworthy exception.

A 2.34 ct Fancy Intense yellow-green type IaAB diamond was found to have abundant silicate inclusions with a more systematic pattern delineating growth layers (see above). Collectively, the inclusions outline con centric octahedral layers. The growth layers are made even more noticeable by a sort of optical graining that could be caused by layered distortions in the diamond crystal from variations in nitrogenconcentration. Many of the individual inclusions have an elongate or flattened oblate shape that conforms to the growth layering (bottom image). Thus, both the shape of individual inclusions and the collective distribution of multiple inclusions imitate the geometry of concentric octahedral diamond growth. This kind of symmetrical, growth-outlining texture is rarely observed in diamond.

The vibrant orange and green inclusions were identified as almandine-pyrope garnet and omphacitic clinopyroxene, respectively. Such mineral inclusions are distinctive of diamonds grown in an eclogite host rock, one of two common diamond rock types in the lithospheric mantle, the other being peridotite (S.B. Shirey and J.E. Shigley, “Recent advances in understanding the geology of diamonds,” Winter 2013 G&G, pp. 188–222). Diamonds like this one with eclogitic inclusions are sometimes called E-type, while those with peridotitic inclusions are denoted as P-type.

This is an interesting sample from a geological perspective. There are still many unanswered questions about exactly how diamonds form. Detailed analysis of this sample could provide valuable clues as each layer captures successive chemical snapshots of the diamond growth process. Of particular interest here is the question of how long it takes to make a diamond. It is possible that this diamond grew over the span of millions of years and the inclusions serve as an encrypted record of the process. @chapter:39 @chapter:1 @chapter:39


# Publication Year: -
# Title: Garnet Care and Cleaning Guide
# Abstract: Garnets have been among the most popular gemstones in jewelry throughout history. They can provide a lifetime of enjoyment with proper care. - © GIA & Tino Hammid, courtesy of 23rd St. Shoppe

Hardness and toughness
Gem and mineral hardness is measured on the Mohs scale. The numbers are based on the relative ease or difficulty with which one mineral can be scratched by another. But the Mohs scale is deceptive. The steps between the minerals are not evenly spaced. For example, diamond is only one number away, but it’s many times harder than gems in the corundum family.

Depending on type, garnet hardness ranges from 6.5 to 7.5 on the Mohs scale. For example, almandine, pyrope, spessartine, and tsavorite are on the harder side while demantoid is a bit softer.

Garnets have fair to good toughness, making them durable enough for all jewelry styles as long as they are treated with the proper care. Garnets should not be subjected to any hard blows or rough wear.

	Depending on type, garnet hardness ranges from 6.5 to 7.5 on the Mohs scale.
Stability
Garnets are stable to light and chemicals. They can be attacked by hydrofluoric acid.

Cleaning
Warm soapy water is always safe for cleaning garnets. The ultrasonic cleaner is usually safe except for stones that have fractures. Steam cleaning is not recommended.

Treatment and durability considerations:
Garnets might rarely be treated by fracture filling. Only warm soapy water should be used to clean fracture-filled stones. @chapter:16 @chapter:0 @chapter:16


# Publication Year: -
# Title: Mozambique Copper Bearing Tourmaline Mine
# Abstract: Moussa KonateBC Gemas do Brazil and Mozambique Gems

Interview with Moussa Konate, BC Gemas do Brazil and Mozambique Gems
For some time, Brazil was considered the sole legitimate source of the electric-blue tourmaline known as Paraíba. As a result, Mr. Konate and his company met considerable resistance when they first started mining similar material in Mozambique.

The market soon accepted his copper-bearing Paraíba tourmaline because, he says, it became about the quality rather than the name.

Every day, miners dig out the ore and bring the material to the washing plant, where they currently wash about 11 16-ton truckloads per day, up from 6 to 7 at the beginning. Mr. Konate’s stated goal is to increase production to 30 truckloads daily. The mine, which started up in 2006, yields about 1 to 2 kg (about 2 to 4 lbs.) of good-quality tourmaline a month, mostly in 1 to 5 gram (under .20 ounce) sizes, but up to 200 grams (7 ounces) in some rare cases.

Since starting operations, his company has explored barely 2 hectares (5 acres) of their 300-hectare (740-acre) claim, leaving plenty of area still unexplored. The company’s license is in effect until 2036.

Mr. Konate’s company is also exploring for aquamarine in the mine’s northern region. They’ve had some success, finding scattered pieces of cabochon material, but they’re still looking for the pocket that will lead them to maximum yield. As he says with a smile, “Then we can invite you guys to come and see us take out 100 kilos (220 lbs) of pure aquamarine.” @chapter:30 @chapter:0 @chapter:30


# Publication Year: 2018
# Title: Book Review: Women Jewellery Designers
# Abstract: By Juliet Weir-de La Rochefoucauld, hardcover, 360 pp., illus., publ. by ACC Art Books Ltd., Woodbridge, Suffolk, UK, 2017, US$95.00.

This is a beautiful book—from the protective slipcover to the lush photography, it is a high-quality production.

The subject matter is most interesting as well. This massive volume is devoted exclusively to women designers who have made names for themselves through their vision, creativity, and pioneering of techniques and designs. The number of artists whose work is covered in the book is quite impressive—it’s a virtual “who’s who” of most of the important women in the world of jewelry design from the early 20th century through today. The book includes well-known artists along with designers that may not be familiar to everyone. Certainly a number of them were new to me.

The book begins with a very brief discussion of women jewelers of the Arts & Crafts movement. This was a period in time (at the turn of the 20th century) when women were “allowed” to make jewelry under their own names. As the curator of an exhibition on this very subject (Maker and Muse: Women and Twentieth Century Art Jewelry) I have mixed feelings about seeing such a brief section on these pioneering jewelers. I understand that the author did not want to leave them out of the book altogether because the women she does write about at length stood on the shoulders of the Arts & Crafts jewelers. But by writing such a brief section on them (only four pages of a 358-page book) versus the lengthy descriptions of later women, it seems that somehow the contribution of Arts & Crafts artisans to jewelry history is diminished. It seemed as if this early chapter was an afterthought, not a beginning.

However, this is a minor complaint. The book covers the work of an amazing number of mostly “high” jewelry designers ranging from Coco Chanel, Suzanne Belperron, and Jeanne Toussaint—who designed for Cartier in the early to mid-period of the 20th century—to contemporary jewelers including Paula Crevoshay, Anna Hu, and Elsa Peretti. Most of the artists whose work is featured in Women Jewellery Designers have (or are) creating luxury jewels. Their pieces can take your breath away with their beauty. But they also possess the opulence of jewelry laden with precious stones and precious materials that few of us will ever be able to afford. It’s a somewhat curious but interesting mix of artists whose work is discussed in the various sections of the book: “Between the Wars: The Awakening;” “Post-War to 1980s: Full Steam Ahead—The Search for the Perfect Design;” “What Is Happening Now in the Field of Jewelry Design;” and three appendices in the back, “The Designers” (additional information), “Toussaint,” and “L’Affaire Chanel.”

Several others that are included were modernist artists like Vivianna Torun Bulow-Hube and Nanna Ditzel, who designed pared-down, minimally ornamented pieces for the firm of Georg Jensen in the 1950s and 1960s. Their work was more commercially available at affordable prices. The work of Tiffany & Co., with designers like Angela Cummings, Elsa Peretti, and Paloma Picasso, were designed for the upscale mass market. To me, these women are in a totally different arena than the work of Cindy Chao, Alexandra Mor, Marilyn Cooperman, and Victoire de Castellane, to name a few covered in this book. Artists like Margaret De Patta, Margaret Craver, Wendy Ramshaw, and Gerda Flöckinger are what I would designate “studio jewelers”—artists who created one-of-a-kind handmade pieces without help from model makers, gemstone cutters, and other assistants. Craver was also well-known as an educator and for training World War II veterans in metalsmithing techniques. Line Vautrin, who made jewelry highly prized by collectors today, is perhaps best known for the bronze objects she created, especially her coveted mirrors.

All of the women included in this book produced groundbreaking work in their time or are currently making spectacular jewelry. However, if this was a book about male and female jewelers, it is unlikely the mix of artists with very different oeuvres would be included in the same book. Despite the disparate categories in which they worked the jewelers here are united by virtue of their gender and talent rather than the genres in which we normally think of their work. What does bring these artists into the same circle of importance is the quality and originality of their output. The photography—of multiple pieces by each artist—well illustrates each artist’s capabilities and dazzles the eye.

I found of particular interest the stories of the women who designed for the big houses such as Jeanne Toussaint for Cartier and Renee Puissant at Van Cleef & Arpels, who are somewhat unsung heroes of jewelry. Apparently the author was also fascinated by these women, providing additional information about Cartier’s Jeanne Toussaint in an appendix. She reproduces a recently found letter proving Toussaint become involved with Cartier at a much earlier date than previously thought. I’m sure the discovery of this letter was one of those wonderful moments that writer/researchers live for uncovering.

If you are interested in the incredible body of work by important women jewelers, whether they worked on their own or designed for important firms, this is the book for you. Even if you just love beautiful jewelry, you won’t be disappointed in this absorbing and impressive book. @chapter:20 @chapter:2 @chapter:20


# Publication Year: 1988
# Title: Chrysoberyl and Alexandrite from the Pegmatite Districts of Minas Gerais, Brazil
# Abstract: This fourth article in the author's series on the pegmatite districts of Minas Gerais, Brazil, focuses on chrysoberyl, particularly the rare but coveted varieties cat's-eye and alexandrite. Most of the cat’s-eye chrysoberyls on the gem market today come from Brazil, primarily from the region around the Americana and Santana valleys. This article examines some of the more important mines in this region, with a detailed description of the Barro Preto deposit. Farther south, the Malacacheta area has produced a number of fine alexandrites during the last 13 years. Since October 1986, however, it has been overshadowed in both quality and quantity by the small Lavra de Hematita, which produced 50 kg of fine alexandrite in less than three months. These two occurrences are also described in detail. @chapter:6 @chapter:0 @chapter:6


# Publication Year: 2015
# Title: Color Zoned Emerald
# Abstract: Figure 1. Left: When table-down, the stone is mainly colorless, showing some partially green overgrowth. Right: Face-up, the faceted stone displays an even and attractive dark green emerald color. Photos by Jonathan Muyal.

Cutting style and orientation are important considerations when cutting natural crystals with strong color zoning. Careful placement of these zones can distribute color by reflection, creating a uniformly colored finished stone when viewed face-up.

Recently, the Carlsbad laboratory received a 33.73 ct green octagonal step cut showing strong color zoning (figure 1). The gem cutter skillfully placed a thin green color zone in this emerald along the pavilion facets so that the stone would appear uniformly green when in a face-up position. Standard gemological testing revealed a refractive index (RI) of 1.571–1.578 and a specific gravity (SG) of 2.72. Chromium-related features were observed in the red end of the spectrum when examined with a handheld spectroscope. All of these properties were consistent with emerald. During microscopic examination, minute jagged fluid inclusions and growth tubes were observed, proving the stone was of natural origin (figure 2).

Figure 2. When viewed from the side, irregular green color zoning is observed along with
minute jagged fluid inclusions. Photomicrograph by Jonathan Muyal; field of view 14.52 mm.
Interestingly, the stone showed a strong green color zone very close to some of the pavilion facets, as well as hexagonal columnar-like growth and irregular zoning (figure 3). This type of zoning represents a late-stage influx of chromium and vanadium into the genetic environment, which were then incorporated into the crystal lattice of the beryl. Energy-dispersive X-ray fluorescence (EDXRF) revealed high levels of Cr and V in the green color zone, which was consistent with the observed color. Although similar zoning has been observed in emerald previously (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Volume 3, Opinio Verlag, Basel, Switzerland, 2008, pp. 433–434), the zoning in this specimen was quite distinct.

Figure 3. The colorless spots indicate parallel columnar growth of white beryl overgrown
by green emerald. Photomicrograph by Jonathan Muyal; field of view 19.27 mm.
This emerald demonstrates the significance of proper orientation and cutting style in fashioning high-quality gem materials. @chapter:10 @chapter:0 @chapter:10


# Publication Year: -
# Title: Alrosa Claims Wider Role in Diamond Market with Hong Kong Auction
# Abstract: The highlights of the Alrosa fancy colored diamond auction in Hong Kong: A 15.11 ct Fancy Vivid orangy yellow with a minimum bid of $1.2 million and an 11.06 ct Fancy Deep purple pink that carried a reserve of $3.3 million. Both diamonds were graded by GIA. Photo Russell Shor/GIA

Alrosa, Russia’s diamond mining and marketing arm, auctioned more than 250 polished fancy colored diamonds for $9 million at a tender sale during the September Hong Kong Gem and Jewellery Fair. While the auction was important, even more significant is that it demonstrates that this once-aloof diamond producer is asserting itself into the world diamond market.

The company, the largest diamond producer by volume and second largest by revenue in 2017, publicized the sale well in advance and signaled that it plans to become more involved in diamond marketing in the future – and become the world’s major source for fancy colored diamonds.

Alrosa took the unusual step of inviting members of the trade and media to view its colored diamond collection in a meeting room in a floor above the show. In the past, it kept sales low key, inviting mainly its own clients to bid on rough and polished diamonds without outside publicity.

Evgeny Agureev, director of Alrosa’s United Selling Organization, the division that sells productions of all of Alrosa’s mines, said this was the first of what will be yearly or twice-yearly auctions of diamonds that “fill the fancy colored diamond gap” after Australia’s Argyle mine closes in 2020 or 2021. He added that the company also is looking into establishing a Russian brand for its diamonds, though those plans remain “very preliminary.”

For many years, Alrosa was a passive, though major, seller of rough diamonds. Like De Beers, it sold its rough through a network of selected clients (Alrosa Alliance) in a series of 10 sales each year, but did little to stimulate demand downstream. The company rarely participated in or contributed to industry marketing initiatives until three years ago when it joined the Diamond Producers Association (DPA). Alrosa only began to contribute in a big way to the DPA last year when it kicked in $25 million, more than one-third of the group’s total marketing budget of $70 million.

Alrosa has also opened new sales offices in New York, where it plans to auction 80 large diamonds later this year, and expanded operations in its other markets.

The highlights of the Hong Kong auction were an 11.06 ct Fancy Deep purple pink that carried a reserve of $3.3 million and a 15.11 ct Fancy Vivid orangy yellow that had a minimum bid of $1.2 million. There were 146 other fancy colored diamonds ranging in weight from just over 1 ct to 26 carats, carrying a total reserve price of $10.3 million. The majority of these were yellow, with some modified by orange or brown. Among the smaller diamonds, there were 48 fancy colored pink diamonds, most weighing between 0.3 ct to 0.5 ct. Several other lots featured smaller goods down to melee sizes in various shades of yellow. Of the 250 diamonds offered, 210 were sold.

Mining at the Lomonosov deposit in Western Russia, an important source of Alrosa’s fancy colored diamonds. Photo Russell Shor/GIA
Agureev noted that Alrosa produces 7,000 to 10,000 carats of fancy colored diamonds each year.

A majority of these fancy colors were extracted from Almazy Anabara, an alluvial operation in northwest Yakutia. An increasing number come from the newly developed Lomonosov deposit in the western portion of the country near the border with Finland. GIA reported on this deposit in the Summer 2016 issue of Gems & Gemology.

Alrosa polishes these diamonds instead of auctioning them as rough in hopes of getting better prices, said Agureev, who noted that Alrosa will polish a larger percentage of fancy colored and “special” (colorless over 10.8 cts in the rough) in the future.

“All of these diamonds were polished in our Moscow facility, where we also do our large (colorless) goods,” he said. “It is more costly [to cut diamonds there] but these goods are much less sensitive to labor costs.”

The 11.06 ct Fancy Deep purple pink diamond came from a 27.27 ct rough and took five and one-half months to process from mine to auction, according to Alrosa’s cutter. He said, in a booklet accompanying the diamond, that he needed to polish 36 millimeter-sized “windows” into the mottled surface of the rough to examine the interior of the stone.

The tender sale was well-attended through the entire show, but the final day was cancelled because of Typhoon Mangkhut, which struck Sept. 16 causing some potential buyers to miss the sale.

Alrosa also auctioned 28 polished colorless diamonds over 5 carats, the highlight being a matched pair of E color round brilliants, weighing 5.18 and 5.19 cts, respectively.

The company produced 39.6 million carats of diamonds last year, 3% higher than 2016’s total of 37.4 million carats. Alrosa’s revenues were $4.3 billion, slightly below 2016’s total of $4.5 billion. @chapter:49 @chapter:3 @chapter:49


# Publication Year: 1996
# Title: Fall 1996 G&G Lab Notes
# Abstract: Aragonite
Different Colors from the Same Rough Diamond
Imitation Diamond Crystals: Cubic Zirconia
Natural Rough Diamond with Unseen "Flaws"
Fancy Intense Pinkish Orange Diamond
A Suite of Treated-Color Pink-to-Purple Diamonds
Herderite
Jadeite
Opal: an Assemblage
Assembled Cultured Blister Pearls with Thread-Like Inclusions
Single-Crystal Green Quartz
Unusual Treated Natural Sapphire
Flame-Fusion Synthetic Sapphire

To view the full section, download the PDF above. @chapter:43 @chapter:1 @chapter:43


# Publication Year: 2019
# Title: New Designs from Paula Crevoshay
# Abstract: Figure 1. Paula Crevoshay’s “Penguin” pendant features 120 white moonstones, 10.09 carats total. It also contains 152 black diamonds with a total weight of 4.22 carats, 14 yellow diamonds (0.43 carats total), and eight orange opals (0.27 carats total), set in 18K gold. Photo by Robert Weldon/GIA.

	New designs from Paula Crevoshay

Paula Crevoshay continues to delight with whimsical designs and masterful control of color and light. At the AGTA show, she introduced several new pieces in her collection of threatened and extinct species, such as the charming penguin shown in figure 1. Crevoshay currently has a one-woman exhibition at the Natural History Museum of Los Angeles County entitled Art of the Jewel: The Crevoshay Collection, which explores her exhaustive process for creating jewels depicting nature all the way back to the uncut gem materials. A collaboration with lapidary intarsia master Nicolai Medvedev yielded the breathtaking “Garden of Delight” mystery box (figure 2), replete with a blue columbine on top, gold insects on each corner, mating hummingbirds that arise when the box is opened, and a delicate string of ladybugs making their way up the hinge. Another piece that demonstrates Crevoshay’s artistry is the “Anemone” pendant/brooch, which mixes greens and blues from a variety of gems, including sphene, opal, zircon, sapphire, garnet, and apatite (figure 3).

Figure 2. The “Garden of Delight” mystery box (165 × 188 mm) contains lapis lazuli, opal, sugilite, malachite, turquoise, azurite-malachite, rhodochrosite stalactites, and maw-sit-sit. The hummingbirds and branch inside the box feature amethyst, spinel, sapphire, tsavorite, opal, and black diamond. The removable columbine brooch on the lid is set with 13.89 carats of Yogo sapphire along with yellow sapphire and diamond in 18K yellow and white gold. Photos by Robert Weldon/GIA.

Figure 3. Crevoshay’s “Anemone” features a 10.86 ct center sphene surrounded by 16 opals with a total weight of 5.37 carats: four pears, four marquise cuts, and eight rounds. The outer layer contains blue zircon, sapphire, tsavorite, and apatite. Photo by Robert Weldon/GIA. @chapter:25 @chapter:2 @chapter:25


# Publication Year: 2016
# Title: Coesite Inclusions with Filaments in Diamond
# Abstract: Figure 1. Left: A Vivid yellow 0.164 ct diamond containing coesite inclusions. The diamond is 3.52 mm in diameter. Center: Photomicrograph of a dense region of coesite inclusions with filaments; field of view 1.26 mm. Right: A photomicrograph of a single coesite inclusion, with filament gradually going out of focus to the right; field of view 100 μm. Photomicrographs by Jian Xin (Jae) Liao (left) and Evan M. Smith (center and right).
GIA’s New York lab recently encountered an HPHT-treated Fancy Vivid yellow diamond with unique inclusions. The diamond was determined to be HPHT-treated due to the presence of a strong solitary peak at 1344 cm–1 in the infrared absorption spectrum, indicating isolated nitrogen C-centers, a relatively even distribution of color, and the absence of certain peaks in the diamond’s Raman spectrum. However, the color treatment of this diamond was not its most interesting aspect. The diamond was unique for possessing many small inclusions with fine, tail-like filaments (figure 1). Visually, the filaments within this 0.164 ct round brilliant-cut diamond resembled horsetail inclusions in demantoid garnet. Raman spectroscopy of four separate inclusions gave peaks for coesite, a high-pressure SiO2 polymorph (figure 2).

Figure 2. Raman spectra of four inclusions corresponding to coesite with high remnant
pressure inside each inclusion. Spectra have been vertically offset for clarity.
The measured peaks of coesite are shifted with respect to reference spectra due to high confining pressures within each inclusion. The shift of the main peak from its unconstrained position at 521 cm–1 to the measured peak in the inclusions, at 533 ± 1 cm–1, can be used to calculate the internal pressure, which is an incredible 4.3 ± 0.4 GPa (R.J. Hemley, “Pressure dependence of Raman spectra of SiO2 polymorphs: α-quartz, coesite, and stishovite,” in M.H. Manghnani and Y. Syono, Eds., High-Pressure Research in Mineral Physics, AGU, Washington, D.C., pp. 347–359). When a diamond is carried to the surface, the diamond and its inclusions do not decompress coherently, so it is fairly common for inclusions to have some amount of “locked-in” remnant pressure. HPHT treatment is unlikely to have modified this remnant pressure, although the possibility cannot be entirely ruled out without more detailed study. These particular coesite inclusions preserve an especially high pressure because the inclusions are small. Larger inclusions are more likely to crack or deform the surrounding diamond and relieve some of the built-up pressure.

Coesite inclusions are not uncommon in diamond, and they are interpreted to indicate an eclogitic mantle host rock paragenesis. The curvilinear filaments extending from the inclusions are, however, both uncommon and unusual. They have a preferred orientation, extending to the right in figure 1 (center). This direction corresponds with the interpreted direction of growth, outward from the center of the diamond. Most filaments are singular, measuring 20–200 µm long, but a few branch into a fan-like spray of sub-parallel filaments. The thickness of each filament is less than 1 µm, making it difficult to observe or characterize them in more detail. Interestingly, the inclusions occur within discrete regions in the diamond, which correspond to cuboid {100} growth sectors when examined in the DiamondView (short-wave UV fluorescence imaging). A possible explanation for the filaments is that they are grown-in dislocations, originating from the point where the diamond just finished enveloping each inclusion. The filaments resemble the dislocations seen in X-ray topography of natural diamonds (e.g., B. Rondeau et al., “On the growth of natural octahedral diamond upon a fibrous core,” Journal of Crystal Growth, Vol. 304, 2007, pp. 287–293). A dislocation alone, however, would not be optically visible. Small amounts of solid or fluid material trapped with the dislocation might be responsible for its visibility. @chapter:22 @chapter:1 @chapter:22


# Publication Year: 1986
# Title: Spring 1986 G&G Lab Notes
# Abstract: Alexandrite with Unusual Silky Zones
Calcite Marble Beads
Golden Yellow Danburite from Sri Lanka
Diamond Alphabet
Ekanite, a Markedly Radioactive Metamict Gemstone
Emerald with Iridescent Coating
Glass Miciobilles from Arizona
Hornblende Amphibole, Magnesian Hastingsite
Lapis Lazuli Imitation, Dyed Blue Quartzite
Oolitic Opal with Chalcedony Matrix
Pearls with Unusual Drilling Features
Sapphire, Pinkish Orange ("Padparadscha")
Yttrium Aluminum Gallium Garnet

To view the full section, download the PDF above. @chapter:2 @chapter:0 @chapter:2


# Publication Year: 2022
# Title: “Fishbone” Inclusion in a Burmese Peridot from Mogok
# Abstract: The fishbone-like inclusion in the Burmese peridot. Photomicrograph by Shu-Hong Lin; field of view 1.32 mm.
Recently, an 83.25 ct cushion faceted peridot with medium dark yellowish green color and good clarity was sent to the Taiwan Union Lab of Gem Research (TULAB) for identification service. This peridot, reported by the owner as from Mogok, Myanmar, was relatively rare in the Taiwanese market because of its impressive size, color, and clarity. Microscopic examination revealed a few short needle inclusions and a fishbone-shaped inclusion (see above), the latter of which is common in peridot from this origin. The backbone appeared to be a long prismatic crystal with some vertical cleavage planes along it, while the smaller branches were composed of parallel tabular inclusions that might result from epitaxial exsolution. Due to peridot’s strong birefringence, brightfield illumination and plane polarized light were adopted to reduce the interference and obtain clear microscopic images. @chapter:6 @chapter:0 @chapter:6


# Publication Year: -
# Title: Bringing Gemology to a Bigger Stage: The 2015 GSA Annual Meeting
# Abstract: The 2015 Geological Society of America (GSA) annual meeting was held Nov. 1–4 in Baltimore. GIA hosted two gemology technical sessions in the conference. Photo by Tao Hsu/GIA.

	Deeply rooted in mineralogy, modern gemology has become increasingly multidisciplinary with the incorporation of theories and techniques from many other scientific branches, especially those in the geoscience realm.

Kate Donovan from the GIA Alumni Association and Dr. James Shigley discuss gemological research and education with visitors to the GIA booth. Photo by Tao Hsu/GIA.

	The annual Geological Society of America (GSA) meeting attracts more than 6,000 geoscientists from all over the world and is one of the best platforms for presenting recent research and finding inspiration for future work. Since 2013, GIA researchers have participated in the GSA annual meeting. At the 2015 conference, held in Baltimore Nov. 1–4, GIA hosted two technical sessions, one oral and one poster, with 26 presentations altogether. At the same time, GIA hosted a booth at the exhibition hall in the Baltimore Convention Center, where representatives from the institute were on hand to answer questions.

	GEMOLOGY ORAL TECHNICAL SESSION

	GIA’s Dr. James E. Shigley and Dr. Wuyi Wang co-hosted the oral session. Dr. George Harlow led with a talk on how gem material studies provide insights on the whole geological system of the Earth. Dr. Wang presented the discovery and distribution of [Si-V]– defects in HPHT synthetic diamonds. This study by a team from GIA’s New York lab challenged the widely accepted theory that [Si-V]– defects only occur in CVD synthetic diamonds, while also showcasing photoluminescence mapping as a powerful research technique.

Dr. James Shigley stands next to the schedule for the gemology oral technical session. Dr. Shigley and Dona Dirlam, director of the GIA library, established the gemology technical sessions at the GSA annual meeting in 2013. Photo by Tao Hsu/GIA.

	Taking a truly multidisciplinary approach, Dr. Laurent E. Cartier from the Swiss Gemmological Institute SSEF worked with a biologist to apply DNA analysis to the origin determination of organic gems. The current study is focused on pearls. For the first time, gemologists can conclusively identify the mollusk species of a pearl. Dr. Cartier and his colleagues are working to perfect this technique and exploring the possibilities with other organic gems such as coral and ivory.

	Dona Dirlam is the director of GIA’s Richard Liddicoat Research Library and Information
	Center. Dona is one of the founders of gemology technical sessions in GSA. Photo by
	Cathy Jonathan/GIA.

	Dr. Karen Smit, a postdoctoral researcher from GIA’s New York lab, studied the Re-Os isotope of sulfide inclusions in type Ib diamond from West Africa. The isotopic study was used to explain the assembly of the Gondwana supercontinent. Next, Dr. Steven Shirey from the Carnegie Institution of Washington presented his Re-Os geochronology study on a sulfide inclusion in superdeep diamond from Brazil. The age of this inclusion indicated crystal recycling facilitated by mental convection beneath. Both studies demonstrate the important role gem materials can play in earth science research.

GSA attendees wait for the gemology oral session to start. Photo by Tao Hsu/GIA.

	Gemological studies of famous stones and historical jewelry pieces are also of great interest. Alan Hart from the Natural History Museum in London explored the creation of the Mogul cut. Using the famous Koh-i-Noor (”Mountain of Light”) diamond from the British Crown Jewels as a case study, Mr. Hart found that differential hardness was the key factor that brought about the Mogul cut with the primitive cutting tools available at the time.  Dr. Raquel Alonso-Perez from Harvard University studied the tourmalines mounted in the Hamlin Necklace, a piece of 19th-century North American jewelry, using both spectroscopic and trace-element analysis.

Dr. Shigley introduces the technical session, co-hosted by Dr. Wuyi Wang. Photo by Tao Hsu/GIA.

	Inclusion study is one of the pillars of modern gemology. GIA’s leading inclusion researcher, John Koivula, pointed out the possibility of misidentifying synthetic corundum as natural heat-treated material. Experimental studies proved that heat-fused cracks generated in both pulled and flame-fusion synthetic corundum look virtually identical to the features associated with so-called flux-healed natural stones. Dr. Aaron Palke, a postdoctoral researcher from GIA’s Carlsbad lab, found some unusual glassy melt inclusions in sapphires from southwestern Montana. Dr. Palke and colleagues hypothesized that these sapphires crystallized as peritectic minerals during high-grade metamorphism that generated silica-rich melt and an alumina-rich restite. Future research on this topic may shed light on the source and transportation of Montana sapphires.

	Dr. Steven Shirey answers questions from the audience after his presentation. Photo by
	Tao Hsu/GIA.

	Phenomenal gems are especially interesting materials for scientific study. Dr. Keal Byrne and colleagues from the Smithsonian Institution investigated the luminesce of “chameleon” diamonds, which show an intriguing color-change response to temperature and/or light. Xiayang Lin from Pennsylvania State University discovered the microscopic surface feature that causes iridescence in natural quartz crystals from India.

Dr. Aaron Palke presents his research on unusual glassy inclusions found in Montana sapphires. Photo by Tao Hsu/GIA.

	Researchers also presented studies on American gem deposits. Dr. Michael Wise from the Smithsonian Institution presented his work on the hydrothermal emerald and hiddenite mined in the Hiddenite area of North Carolina. Yury I. Klyukin from Virginia Tech investigated the fluid evolution of the deposit at North American Emerald Minenear Hiddenite. Dr. William B. Simmons from Maine Mineral and Gem Museum shared the recent discovery of gem-quality pollucite in Mt. Mica pegmatite.

Presenters from the gemology oral session. Photo by Tao Hsu/GIA.

	GEMOLOGY POSTER SESSION

	The gemology poster session on Nov. 4 featured twelve posters. Although it was held on the final day of the conference, the session was very well attended. The flexibility of presentation time and format allowed for dynamic discussion between exhibitors and viewers.

The gemology poster session attracted considerable attention on the last day of the GSA conference. Photo by Tao Hsu/GIA.

	The posters covered a wide range of topics. GIA researchers displayed their studies on micro-diamonds, diamond defect formation, and low–pressure, high-temperature (LPHT) treatment of type Ia diamonds. Sarah Ostrye presented the GIA library’s rare book digitization project. Catherine McManus of Materialytics introduced her project on diamond origin determination using multivariate analysis of LIBS spectra. Gary S. Michelfelder from Missouri State University and coauthors presented their study on the origin of alluvial diamonds in the Coromandel area of Brazil.

	Sarah Ostrye from the GIA library presented the rare book digitization project. Photo by
	Cathy Jonathan/GIA.

	It was also impressive to see Chinese gemology students present their research on newly discovered gem corundum deposit in northeastern China and a color study on tanzanite. Topics and abstracts from the poster session can be found at https://gsa.confex.com/gsa/2015AM/web
	program/Session38771.html.

Dr. Rodney Ewing received the Mineralogical Society of America’s Roebling Award for his distinguished contributions to mineralogical research. Photo by Tao Hsu/GIA.

	In another highlight from the GSA meeting, Dr. Rodney C. Ewing, a professor of geological and environmental sciences at Stanford University, received the Mineralogical Society of America’s Roebling Medal. Dr. Ewing has served on GIA’s board of governors for nine years, providing insightful guidance on research activities and nurturing the institute’s postdoctoral program.

The 2016 GSA conference will be held in Denver and will once again communicate high-quality gemological research to the geoscience world. Photo by Tao Hsu/GIA.

	Since their inception at the 2013 GSA meeting, the gemology technical sessions have provided a broader stage to share important research findings with other scientists. The 2016 GSA annual meeting will be held in Denver, and the gemology session organizers will start work on it soon. @chapter:35 @chapter:1 @chapter:35


# Publication Year: 2023
# Title: 37th International Gemmological Conference
# Abstract: Figure 1. Participants at the 37th International Gemmological Conference, held in October 2023 in Tokyo. Photo by Masayuki Itokazu.
The 37th International Gemmological Conference (IGC) was held October 23–27 in Tokyo, with more than 80 delegates, observers, and special guests from 24 countries attending (figure 1). The IGC, which started in 1951 and takes place every two years, brings together international gemologists, scholars, and researchers to present their work on natural and synthetic diamonds, colored gemstones, pearls, gem treatments, geological and geographical study of gem deposits, and more. This year, IGC delegates had the opportunity to meet with researchers from various earth science disciplines as well as Japanese laboratory gemologists and gem traders at specially organized events.
The opening ceremony began with a welcome from the Japan Jewellery Association, the Japan Gem Society, the Gemmological Society of Japan, and the IGC. Six keynote presentations followed. IGC executive secretary Dr. Jayshree Panjikar discussed the past, present, and future of the conference, beginning with its formation, followed by advancements in gemological science and the latest developments in instrumentation. Dr. Panjikar announced the IGC’s goal of recruiting more young gemologists and scientists by its 100th anniversary in 2052, bringing greater knowledge to the general public and consumers. Professor Hisao Kanda (National Institute for Materials Science, Japan) described the activities of Japanese researchers from 1980 to 2000, particularly in the area of diamond synthesis. Dr. Hanco Zwaan (Netherlands Gem Laboratory/Naturalis Biodiversity Center, Leiden) discussed the differences between natural and laboratory-grown diamond in terms of growth history and conditions and properties. Yuichi Nakamura (Mie Prefecture Pearl Promotion Council) reviewed the status quo of the akoya pearl industry and initiatives for sustainable pearl cultivation in Japan. Professor Pornsawat Watanakul (Kasetsart University) emphasized the importance of research for the gem and jewelry industry, noting examples of in-depth research and advanced technology that are yielding applicable knowledge. Dr. Michael Krzemnicki (Swiss Gemmological Institute SSEF) addressed the issue of classifying colored gems into their respective varieties and presented a number of case studies to illustrate the topic from a gemological laboratory perspective.
At the main conference venue, the National Museum of Nature and Science, participants attended oral and poster presentations, along with the IGC exhibition booth and a demonstration booth showcasing recent advances. Many high-quality scientific talks were presented by IGC members, and some of the presenters were elected as new delegates. Abstracts of the 48 presentations covering topics ranging from diamonds and colored stones to technology and techniques can be viewed on the conference website at www.igc-gemmology.org/s/IGC2023_webfinal.pdf.

Figure 2. Left: IGC participants viewed a 102-ton jadeite boulder at the Oyashirazu jade museum in Itoigawa. Right: During a field trip to Ago Bay, participants observed the implanting of a bead nucleus in a Pinctada fucata oyster. Photos by Ahmadjan Abduriyim.
In addition to the academic program, the IGC Japan committee organized pre-conference and post-conference excursions (figure 2). Before the conference, 32 participants visited the jadeite gorge in the Itoigawa region of Niigata Prefecture and learned about its geological setting and formation and observed the jadeite deposit’s location in serpentinite lenses within a high-pressure metamorphosed complex. After the conference, 25 participants visited the akoya cultured pearl farm at Ago Bay, where they witnessed the bead implantation process and pearl harvesting. In addition to these conference excursions, a tour of Mount Fuji and a visit to the jewelry city of Kofu were organized. @chapter:35 @chapter:1 @chapter:35


# Publication Year: 1982
# Title: Pinpoint Illumination: A Controllable System of Lighting for Gem Microscopy
# Abstract: Pinpoint illumination uses a highly flexible but extremely durable glass fiber-optic bundle that incorporates six easily interchangeable light wands of various shapes and cross-sectional thicknesses down to one millimeter in diameter. The wands are hand held and can be used to illuminate hard-to-reach areas in complex jewelry mountings. With the pinpoint illuminator, a gemstone can be examined from any angle; the light source is placed exactly where it is needed, minimizing glare and unwanted external or internal reflections. @chapter:52 @chapter:1 @chapter:52


# Publication Year: 2023
# Title: Rare Faceted Brucite
# Abstract: A rare and very fragile 3.09 ct brucite. Photo by Annie Haynes.
Gem-quality transparent blue brucite is a very rare, very soft and heat-sensitive magnesium hydroxide (Mg(OH)2) with a Mohs hardness of approximately 2.5–3.0 and perfect cleavage. Brucite was named in 1824 in honor of the first person to describe the species: Archibald Bruce, an American mineralogist, physician, and editor of the American Mineralogical Journal.
Recently the Carlsbad laboratory received for identification services a transparent greenish blue stone weighing 3.09 ct and measuring 9.74 × 9.71 × 5.98 mm (see above). Microscopic observation revealed numerous scratches and abrasions on the surface, as well as strong doubling, some needles, and a large fracture. Standard gemological testing yielded a specific gravity of 2.37. Refractive index was not measured for fear of damaging this soft and fragile stone. A uniaxial optic character was observed with a polariscope and optic figure sphere. Raman spectroscopy confirmed the gem’s identity as brucite. Worldwide, this was the second brucite examined by GIA. @chapter:8 @chapter:0 @chapter:8


# Publication Year: 2018
# Title: Natural Blue and Black Diamonds, a Byzantine Garnet Intaglio, Yogo Sapphires, and “Kasumiga Pearls”
# Abstract: Characterization of diamond—both natural and synthetic—is a common thread for three of our Summer issue’s six papers. This large issue also contains a synthetic diamond chart and our new regular feature “Diamonds from the Deep,” which aims to demonstrate the value of the natural gem to science and our understanding of the earth’s depths.
However, we have much more besides diamond to offer, including Byzantine garnets, Yogo sapphires—which grace the cover—and cultured freshwater pearls from Japan’s Lake Kasumigaura.
First, lead authors Sally Eaton-Magaña, Christopher M. Breeding, and James E. Shigley review the science of naturally colored blue diamonds, which are among nature’s rarest and most valuable gems. This is the second in their series of papers focused on natural-color diamonds. Although boron impurities are top of mind for most people, the authors detail other causes of blue color in diamond, including radiation-induced defects and complex defects involving hydrogen.
Our second paper, by Karen V. Smit, Elina Myagkaya, Stephanie Persaud, and Wuyi Wang, turns the focus to Fancy Dark brown-black diamonds from Zimbabwe’s Marange deposits. Their dark appearance is caused by a combination of tiny, methane-associated graphite inclusions, graphite needles, and brown radiation stains resulting from the diamonds’ billion-year contact with radioactive minerals in the Umkondo conglomerate.
In our third paper, H. Albert Gilg, Karl Schmetzer, and Ulrich Schüssler tell a fascinating story. Using contemporary nondestructive analytical methods, they trace a Byzantine garnet intaglio back to its geographical source in Telangana State, India. The study reveals much about the ancient trading of Indian garnet.
Our fourth article, by Ahmadjan Abduriyim, profiles Japanese freshwater pearls, first cultivated in Lake Biwa, and then in Lake Kasumigaura, where most farms relocated in 1962. Although the production is limited, “Kasumiga pearls” are very attractive, displaying a variety of hues and very good luster.
Sapphires from Montana’s Yogo Gulch are renowned for their vibrant untreated blue color and high clarity. In our fifth article, Nathan D. Renfro, Aaron C. Palke, and Richard B. Berg offer a complete gemological characterization of these unique American gemstones.
Next, Sally Eaton-Magaña and Christopher M. Breeding present a new chart on the growth and characteristics of HPHT and CVD synthetic diamonds, including information on recent advances in technology that enable production of larger, higher-quality synthetics and colorless melee.
I’d also like to draw your attention to our three regular sections. Lab Notes includes entries on advances in the size and quality of synthetic diamonds. Gem News International has something for everyone: a green-blue Maxixe-type beryl, the trace element characteristics of “golden sheen” sapphire, and Ethiopian color-change garnets. G&G Micro-World includes a mushroom preserved in copal, microlite crystals in topaz, and a wurtzite phantom in quartz. This issue also presents a new regular column by Karen V. Smit and Steven B. Shirey on the value of natural diamond to science. In their inaugural entry, the authors examine how diamonds help researchers solve the enigma of water’s presence in the earth’s depths.
Finally, we’d like to remind everyone that we’re fast approaching the last chance to register for the GIA Symposium, so please go to symposium.gia.edu if you haven’t already.
Enjoy our summer edition! @chapter:35 @chapter:1 @chapter:35


# Publication Year: -
# Title: 10 Tips to Boost Your Career
# Abstract: Joel Schechter, CEO of Honora, shared the key attributes his father, Stanley Schechter, taught him to look for in an exemplary employee – loyalty, honesty, respect and attention to detail – at GIA’s 2009 mini Jewelry Career Fair held in Las Vegas. He said demonstrating them is critical to establishing yourself as a standout candidate, especially in a competitive job market.

These are his father’s top 10 tips:

1. Love Mondays. You may not know what your passion is now, but if you care about your work, you may gain passion for it.

2. Sweat the small stuff. You may not be able to control the economy, a lawsuit or losing a major account. But you can control how many paper clips you order if you care about that.

3. Tell the truth. There are no white lies, only white liars. The check is never in the mail. The late piece is never at the polisher. An employee never has a "stomach virus" - you just need a day. Honesty is the ultimate independence.

4. Be willing to do anything. There is no task beneath you, and on an interview profess that. It will mean more than any line item on your resume.

5. Be loyal. Loyalty is a prized commodity. Let your boss know at every opportunity that you have his/her back.

6. Embrace mistakes. Accepting blame allows you to learn to do things differently, and gives you the opportunity to grow. Employers hate every minute someone spends explaining how someone else screwed up.

7. Take risks. Every success you attain can be associated with a frightening risk. We need to take calculated risks, and never believe the only way to do things is the way we've been doing them forever.

8. Respect others. No one has more value because they have more wealth, or is above or below you because of cultural differences. Treat everyone the same until they give you reason not to. Getting along with others is important both for company harmony and increasing the performance of those around you.

9. Give back. It's not all about you. If you don't have money, you can give time, and if you have money, give both.

10. Stand up for your beliefs. Don't wait for a popular consensus that you can agree with or tell an interviewer what you think they want to hear. Let them know at the end of the day you're still a team player, willing to get behind the group decision. @chapter:45 @chapter:3 @chapter:45


# Publication Year: 2013
# Title: Unusual Dumbbell-Like Inclusion in Diamond
# Abstract: Figure 4. This 0.40 ct round brilliant diamond displayed a large, unusually shaped inclusion. Photo by Aurélien Delaunay.

              The French Gemmological Laboratory (LFG) in Paris had the opportunity to grade a 0.40 ct near-colorless round brilliant diamond with a large, unusual inclusion (figure 4). Initial inspection under the loupe showed an unusual internal feature consisting of a thin middle “bar” and two broader appendices (figure 5). Viewed under certain angles, it appeared almost metallic. This feature, which lowered the clarity grade to SI2, was reminiscent of the metallic dumbbell inclusions observed in HPHT synthetic diamonds.

	Figure 5. At first inspection, this dumbbell shape was reminiscent of the metallic flux inclusions seen in HPHT synthetic diamond. Photomicrograph by Aurélien Delaunay; magnified 120×.
DiamondView luminescence images demonstrated that the inclusion was crystallographically oriented, parallel to the edge between two octahedral faces (figure 6). Dumbbell inclusions in HPHT synthetics have a clear crystallographic orientation, often along an octahedral edge as well.

	Figure 6. DiamondView luminescence images demonstrated the diamond’s natural origin, as only traces of octahedral growth were found. The inclusion is crystallographically oriented, parallel to the edge between two octahedral faces, as highlighted by the slightly more inert elongated rectangle beside it. Photomicrograph by Aurélien Delaunay, magnified approximately 60×.
But the stone fluoresced weak blue under long-wave UV radiation and was inert in shortwave UV, a classic luminescence behavior for natural diamond and unknown in synthetic specimens. Furthermore, the infrared absorption spectrum was typical of a natural type IaAB diamond with minor hydrogen. This proved the natural origin of both the stone and its inclusion. With magnification, the inclusion appeared colorless and transparent rather than metallic and opaque, though with a high optical relief. Its morphology was not cuboctahedral—as with inclusions in synthetic diamond—but rounded octahedral. The exact nature of the crystal remains unknown, as we could not obtain a Raman spectrum due to its intense luminescence, but colorless inclusions in diamonds are often forsterite. @chapter:22 @chapter:1 @chapter:22


# Publication Year: 2010
# Title: Bastnäsite-(CE) and Parisite-(CE) from Mt. Malosa, Malawi
# Abstract: Large crystals of the rare-earth carbonates bastnäsite-(Ce) and parisite-(Ce) have been collected from alkaline pegmatites at Malawi’s Mt. Malosa, where they occur associated with aegirine, microcline, and several other unusual accessory minerals. Only small portions of some crystals are suitable for cutting into attractive gems, because most of the material is opaque or heavily fractured. This report presents the gemological and chemical properties of Mt. Malosa bastnäsite-(Ce) and parisite-(Ce) gemstones. This area shows good potential for future production of these rare-earth carbonates, although cut stones will continue to be rare. @chapter:12 @chapter:0 @chapter:12


# Publication Year: 2017
# Title: Visit Europe’s First Diamond Mine
# Abstract: If variety is the spice of life, you’ll appreciate our Summer 2017 issue. We offer six diverse articles featuring Russia’s Lomonosov diamond mine, carbonado, photoluminescence (PL) mapping, Vietnamese tourmaline, nephrite color determination, and Montana sapphire. In addition, we provide a full-color wall chart of characteristic sapphire inclusions.

Photoluminescence mapping shows great promise for detecting sophisticated diamond color treatments.

In August 2016, GIA’s Dr. Karen Smit and Russell Shor were fortunate enough to visit Russia’s Lomonosov diamond mine. This deposit is located about 60 miles (100 km) north of the historic port of Arkhangelsk, at a northerly latitude much like Canada’s Diavik mine. In our lead article, they share insight into its geology, operations, and diamond production. Rooted in younger Proterozoic rocks—similar to Australia’s off-craton Argyle lamproite pipe— Lomonosov’s two kimberlite pipes produce a high proportion of small gem-quality diamonds, including a tiny amount of highly valuable fancy colors, including pink. Named for its resemblance to charcoal, carbonado is one of the most intriguing diamond forms. In our second paper, Prof. Stephen Haggerty of Florida International University reviews his findings from a study of hundreds of examples from the only known sources: Brazil and the Central African Republic. He evaluates origin theories, including terrestrial and extraterrestrial models.

High-speed PL mapping can plot the distribution of optical centers in diamond. In his study, GIA research associate Lorne Loudin examines an unusual irradiated HPHT synthetic diamond of mixed type. He demonstrates a clear correlation between concentration of optical centers and diamond growth sectors, confirming that the technique shows great promise for detecting sophisticated diamond color treatments.

Luc Yen tourmaline is the subject of our next paper, from Nguy Tuyet Nhung of the Gemmological Center of the Vietnam Gemstone Association and a team of researchers. They survey the gem’s distribution in the area, its geology, and suitability for use as gems, carvings, or mineral specimens.

In our fifth paper, Xiaoyan Feng, senior engineer at NGTC in Beijing, and her research team use Raman spectroscopy to investigate and define color boundaries in nephrite from China and Taiwan.

Following the Winter 2016 emerald wallchart, we present the next in the series, which features some characteristic internal features of natural, treated, and synthetic sapphire. The chart is from the same team of inclusion specialists, led by GIA’s Nathan Renfro and John Koivula.

In our final article, Tao Hsu and her coauthors survey alluvial sapphire production in the U.S. state of Montana. They note the prevalence of small-scale mining and the importance of gem tourism, but indicate that larger, mechanized operations are expanding production at these sources.

Our Lab Notes section offers entries on melee-size CVD synthetics in parcels and jewelry, CVD synthetic overgrowth on natural diamond, and non-nacreous “rosebud” conch pearls. Topics in our Micro-World section include kyanite in diamond and molybdenite “phantoms” in quartz, while GNI features new gem finds such as Ethiopian sapphires and common opal from Mexico.

Please enjoy the Summer edition! @chapter:44 @chapter:1 @chapter:44


# Publication Year: 2022
# Title: Quarterly Crystal: Panasqueira Quartz
# Abstract: Figure 1. Weighing 751.95 ct, this parallel cluster of two quartz crystals contains a directional phantom plane composed of numerous green to near-colorless hexagonal inclusions. Photo by Adriana Gudino.
With its relatively high hardness and high degree of transparency, colorless rock crystal quartz is the perfect host for an abundance of fluid and mineral inclusions. As a common crustal mineral, it sometimes forms as solid single crystals and crystal clusters.

Figure 2. The translucent green-colored crystals along the phantom plane in the Portuguese quartz were identified as fluorapatite by Raman analysis. Photomicrograph by Nathan Renfro; field of view 12.47 mm.
This issue’s Quarterly Crystal, a 751.95 ct double crystal measuring 110.54 × 50.30 × 24.82 mm from Minas da Panasqueira in Portugal (figure 1), comes from the personal collection of Jordi Fabre of Fabre Minerals in Barcelona. Examination of the two parallel quartz crystals revealed numerous colorless to green, transparent to translucent euhedral inclusions, identified by Raman analysis as fluorapatite (figure 2). Some of these fluorapatite inclusions surrounded a much larger dark brownish orange protruding crystal confirmed as cassiterite (figure 3).

Figure 3. Using Raman microspectrometry, this single protruding dark brownish orange crystal was identified as cassiterite. Photomicrograph by Nathan Renfro; field of view 13.64 mm.
The colorless to green fluorapatite crystals show directional deposition and are along a phantom plane, situated only on one side of the quartz specimen. This suggests that they are syngenetic with the quartz host.
Quartz is relatively common at the Panasqueira mine. This “floater” quartz crystal group, which is recrystallized at its base, is an excellent host for the numerous inclusions of fluorapatite and the solitary cassiterite crystal. @chapter:15 @chapter:0 @chapter:15


# Publication Year: 2023
# Title: Spotlight on Natural Nacreous Pearls
# Abstract: A pair of earrings with unoiled emeralds weighing about 8 ct total, natural pearls measuring 9.5–10.0 mm, unheated Burmese rubies weighing just under 5 ct total, and diamonds set in yellow gold. Photo courtesy of ProVockative Gems Inc.
A natural pearl forms in the interior of a mollusk within a naturally formed pearl sac without human intervention. The use of natural pearls goes back thousands of years, and these biogenic gem materials have been treasured in jewelry and adornment throughout human history. In general, pearls can be separated into two varieties based on surface structure: nacreous and non-nacreous. The nacreous pearls are more common in the market. These are formed by a layered structure of aragonite platelets together with organic substances as well as water, and they normally display a pearly luster.
At the AGTA show, Alex Vock of ProVockative Gems Inc. (New York City) shared some of his expertise in natural saltwater nacreous pearls. With more than 30 years in the business, he is considered an industry leader specializing in signed collectible jewelry, natural gemstones, and natural pearls. He had several pieces on display, including an attractive pair of natural pearl earrings set with unheated Burmese rubies and unoiled emeralds (see above).
Vock discussed the global market for natural nacreous pearls, noting that it was greatly diminished by the 1980s due to the prevalence of cultured pearls. However, regions such as many of the Gulf countries and India did not feel pressure from the cultured pearl market. These countries have led a resurgence of natural pearl’s popularity, specifically with Basra pearls. These originate in the Arabian (Persian) Gulf, and their namesake is the city of Basra in Iraq. Historically, Basra was the center of natural pearl commerce, with the greatest selection of natural pearls and the most informed dealers.
Vock mentioned that the most prized natural nacreous pearls today are from either the Gulf region or Australia. Currently, both regions produce what dealers describe as “new material,” which are freshly harvested natural pearls. Natural pearls form in the mantle of the pearl mollusk shells, whereas cultured saltwater pearls grow inside the gonad of the mollusks. Many natural pearls have a large flat surface, similar to a button shape, because they grow against the mantle. For that reason, round, oval, and drop-shaped pearls are rarest and most valuable.
When comparing pearls from the two regions, Vock explained, there are some differences. Basra pearls usually have a warmer bodycolor, while Australian pearls tend to be whiter. Also, Basra pearls are often rounder than their Australian counterparts. In fact, the Gulf region has the highest percentage of round natural nacreous pearls of any producing area. He credited this to the smaller shell of the Gulf region mollusks.

	Spotlight on Natural Nacreous Pearls

To see Alex Vock explain these common appearances with examples from his current collection, see the video above. @chapter:53 @chapter:4 @chapter:53


# Publication Year: 2022
# Title: A Synthetic Moissanite Presented as Natural Diamond Rough
# Abstract: Figure 1. This 7.42 ct light bluish green synthetic moissanite, submitted as a diamond, displays triangular features on each of the octahedral faces. Photo by Jian Xin (Jae) Liao.
A 7.42 ct light bluish green specimen (figure 1) submitted to the New York lab for a colored diamond identification and origin report was identified as a synthetic moissanite crystal carved to resemble a natural diamond rough. Since synthetic moissanite resembles diamond at a glance and has a similar specific gravity and “heft,” it could easily be mistaken for natural diamond. The sample was first identified as synthetic moissanite using Fourier-transform infrared (FTIR) spectroscopy (figure 2). The resulting data displayed a distinctive moissanite spectrum, with peaks occurring at 2079, 2297, and 2392 cm–1 (A.M. Hofmeister et al., “Optical constants of silicon carbide for astrophysical applications,” Astrophysical Journal, Vol. 696, No. 2, 2009, pp. 1502–1516). This finding was confirmed with an analysis of the Raman spectrum, which showed strong 767, 788, and 798 cm–1 peaks, also consistent with synthetic moissanite (figure 3). Although natural moissanite does exist, crystals are tiny and fragmented. Gem-quality specimens have not yet been found (Summer 2014 Gem News International, pp. 160–161).

Figure 2. The peaks at 2079, 2297, and 2392 cm–1 displayed in this FTIR spectrum are consistent with synthetic moissanite.

Figure 3. Raman spectroscopy confirmed the identification as synthetic moissanite, with peaks at 767, 788, and 798 cm–1. (The sharp peak at 970 cm–1 suggests a hexagonal 6H type of silicon carbide.)
The turbid and stained 7.42 ct synthetic moissanite was shaped into a slightly rounded octahedron with prominent stepped edges. Octahedra belong to the cubic crystal class; both natural and synthetic SiC belong to the trigonal class and always display hexagonal prismatic to tabular forms. It was concluded that the synthetic moissanite rough had been carved into an octahedron, and that the detailing of the stepped edges and coarse textures were specifically chosen to imitate the appearance of a natural diamond octahedron that had been partially resorbed by kimberlitic magma, such as the natural diamond in figure 4. Although sharp and well-formed diamond octahedra are occasionally found preserved in mantle rocks entrained in kimberlitic eruptions, the vast majority of natural diamond crystals are exposed to corrosive kimberlitic fluids during their ascent through the cratonic mantle and display a wide variety of resorption textures (R. Tappert and M.C. Tappert, Diamonds in Nature: A Guide to Rough Diamonds, 2011, Springer Verlag, Heidelberg, Germany).

Figure 4. Exposure to kimberlitic fluids rich in O2 and H2O creates varied shapes and textures in natural diamond octahedra. This natural green diamond, known as the “Matryoshka” (Spring 2020 Lab Notes, pp. 127–129) has resorbed points and edges as well as trigonal etching on the {111} faces. Photo by Jian Xin (Jae) Liao.
This investigation is a reminder to take caution when identifying gemstones, as intentional material processing steps such as these may be used to deceive consumers and could damage the integrity of the gem trade. @chapter:43 @chapter:1 @chapter:43


# Publication Year: -
# Title: Bench Tip #10: Use Vector Tightening to Overcome Metal Memory in Prongs
# Abstract: Vector tightening

Gemstones that become loose can cause damage to both the gem and the setting. A regular inspection of jewelry can catch this problem in its early stages, before too much damage is done. Vector tightening prong-set stones is a quick, safe, and effective way to secure gemstones.

We will use a four-prong head with a round brilliant-cut stone as an example. If you try to tighten the stone by simply pushing the prongs in toward the center of the stone -- seemingly the most direct way -- it probably won’t be secure. That’s because the “memory” of the metal in the prong will cause it to spring back to its original position, and the stone will still be loose. In vector tightening, you move the prongs in two different directions (vectors) to overcome the metal memory.  The prongs end up closer to the center of the stone, and are able to hold it tightly. You can use flat or chain-nose pliers to vector tighten, but parallel-jaw pliers work best.

Imagine the setting in a fixed position to help you better visualize the procedure; however, at the bench you would turn the setting around to get the best leverage. This way, the prongs being adjusted won’t get mixed up.

First, gently squeeze the two prongs on the right side (upper and lower right) toward each other. Next, do the same thing with the prongs on the left side. As you squeeze the prongs toward each other, they will “slide” around the contour of the stone. Don’t squeeze too hard -- just reduce the distance between the side prongs by roughly one-third.

At this point, the space between the top two prongs and the bottom two prongs should appear too large, and the space between the two prongs on the right and left sides should appear too small.

Next, squeeze the top two prongs (upper left and upper right) toward each other so they end up with what looks like the original spacing. Repeat with the bottom prongs. The gemstone is now tight, with the prongs evenly spaced around it.

The movement of the prongs in two directions, first toward the sides and then toward the top and bottom, provides tension in the prongs so they are somewhat spring-loaded and hold on to the gemstone securely. @chapter:50 @chapter:3 @chapter:50


# Publication Year: 2013
# Title: Zircon and Geikielite from Sri Lanka with Artificial Stars
# Abstract: Two asteriated cabochons acquired in Sri Lanka were identified as natural zircon and geikielite. But the six-rayed star had not been observed in natural star zircons, and the eleven-rayed star of the geikielite was crystallographically “impossible.” Microscopic observation clearly showed both had been created by a fine scratching of the cabochon domes.

										In both cases, the surfaces appeared to have been produced by short parallel scratches. The center of each star was a white spot, and their branches were short, sometimes missing or undulating and hatched. The effect is formed mainly by diffraction at the scratches rather than reflection from needles or hollow tubes, like in natural stones. When the focus of the microscope is lowered some millimeters from above the cabochon surface through below the surface, the star gets finer and is sharpest below the surface, in contrast to natural stars, where the sharpest star seems to hover above the surface.

										The features described above, along with some other characteristics mentioned by Steinbach (2011), allow a safe distinction of scratched star stones from their natural counterparts mostly by simple observation with the naked eye.

Abstracted by Rolf Tatje @chapter:26 @chapter:0 @chapter:26


# Publication Year: -
# Title: De Beers Raises Prices at April Sight, Basel Business Report
# Abstract: Mozambique ruby, which rivals Burmese ruby in color, was readily available at Baselworld and helped temper the lofty prices Burmese dealers have been asking in recent years. These small, high-quality clean rubies are from Montepuez, Mozambique. Photo by Vincent Pardieu/GIA

                      De Beers, as expected, boosted prices at its April 1-4 sight, which totaled about $740 million. The increase, averaging 2.5% to 3%, was concentrated in a relatively narrow range of goods ‒ mainly those that would polish out to half- or one- carat gems‒ that were in high demand.

The price increase was expected given concerns in the past two months that the rough market was “overheating” and once again falling into speculative buying. Polished prices also have edged up a few percentage points from January, but are still lagging behind rough increases, which have again squeezed profits.

The activity in the rough market has prompted the industry’s leading lenders to restate the new credit policies they announced last fall: they will provide funding for 70% of the value of rough purchases, not 100%, to dampen speculative buying. As the results of recent tender sales indicate, however, a number of companies remain willing to bid up rough prices even with reduced credit.

Unlike last year, sightholders did not defer any purchases at this sight. One reason is that the most of the rough could still bring a small profit after polishing. Another is that De Beers begins its selection process for the next sight period in June and clients may want to make a favorable impression.

Most diamond traders believe the rough market will be quiet for the next several months to see how the year shapes up.

BASEL REPORT: Business was subdued overall at the recently concluded Baselworld (March 26-April 3). Sales in the gemstone hall were slightly up from last year, but buyers generally passed on many of the extreme high end pieces: colorless diamonds over 10 carats in high colors and clarities and larger pink and blue fancies.

Large colorless diamonds were priced 15% to 20% higher than last year and fancy colors were up 20% - 30%, but these prices apparently went beyond the limit for many well-heeled buyers. Large fancy yellow diamonds were in abundance at the show, but dealers reported that demand was much weaker than in the past.

What did sell were colorless diamonds in the 3 carat to 5 carat range, which were up about 10% in price from last year. Buyers felt these goods were moving well in consumer markets in the U.S. and Asia. China demand has slowed considerably, but is still reasonably healthy, while the U.S. is showing signs of a much better year.

In colored stones, Mozambique ruby, which rivals Burmese ruby in color, was quite abundant in high colors. This has helped temper the lofty prices dealers of Burmese material were asking in recent years.

Demand for no-heat sapphire remained strong. That “anti-treatment” sentiment has spread to emeralds, with a number of dealers offering “no-oil” goods. Prices for untreated top goods, with the exception of ruby, were 20% to 30% higher than last year, but, as with diamonds, buyers were very selective.

Indeed, dealers and buyers alike said that prices of colored stones, especially the higher qualities, have risen beyond what can be justified by demand, so they are limiting buying to only what they can immediately sell. “No one wants to be caught with lots of goods in a price correction,” one exhibitor said.

This year, two additional shows opened to capitalize on the overflow from Baselworld.

The Rapaport Diamond Show, held near the main rail station in Basel, featured nearly 70 exhibitors, including a delegation from the New York Diamond Dealers Club. Business at the three-day show appeared to be slow, though some reported a pickup in traffic on the final day.

The Jewellery & Gem Fair-Europe, in Freiburg, Germany (about 50 miles from Basel), was also new, with approximately 200 exhibitors from around the world. The organizer, UBM Asia, which runs the Hong Kong shows, branded it as a sourcing show (in contrast to Baselworld as a branded merchandise show). Accordingly, most of the exhibitors and products were aimed at the middle- and lower-priced markets. The show was well-attended for the first day, though some buyers complained about the transportation to and from Baselworld.

A number of exhibitors at Baselworld said they hope the Freiburg show succeeds so they can jump the costly ship in Basel and move into this show, for one-tenth to one-eighth of the cost.

AUCTIONS: Cartier helped set a price record for one of its signature pieces at its April 9 Hong Kong sale. The jewelry house paid $27.4 million for the Hutton-Mdivani jadeite bead necklace; the highest price ever paid for a piece of jadeite jewelry at auction.

The necklace, formerly owned by Woolworth heiress Barbara Hutton who died in 1979, features 27 “highly translucent green jadeite beads” ranging from 15.4 mm to 19.2 mm in diameter.

In addition, a 29.62 carat Burmese ruby set by Cartier, sold for $7.3 million, the highest price ever paid for a ruby at auction. @chapter:37 @chapter:3 @chapter:37


# Publication Year: 2001
# Title: Jeremejevite: A Gemological Update
# Abstract: The submission of a large (4.54 ct) jeremejevite of an unusual—yellow—color to the AGTA Gemological Testing Center prompted a search of the available gemological literature and a detailed examination of five additional samples to learn more about this rare gemstone. It was found that the information in some English-language texts was either confusing or contributed little to our gemological knowledge. The authors confirm the available standard gemological properties and add pertinent data for the UV-visible, infrared, and Raman spectra, as well as for trace elements measured by EDXRF. @chapter:2 @chapter:0 @chapter:2


# Publication Year: -
# Title: Moonstone Description
# Abstract: The beautiful shimmer of light that's characteristic of moonstone is apparent even in its rough form. This special property is maximized by a quality cut. - David Humphrey

                      Moonstone’s delicate beauty and its long-established heritage make it perhaps the most familiar gem-quality member of the feldspar group.

Feldspars are the most widespread minerals in the earth’s crust, as well as some of the most diverse. You can pick up a rock anywhere in the world, and you’ll probably find that it contains a mineral or two from the feldspar group.

	Blue sheen against a colorless background is a prized moonstones combination. This
	suite of finely crafted moonstones is arranged for a designer ensemble.
	- Courtesy Temple Trading Company
Moonstone is a variety of the feldspar-group mineral orthoclase. It’s composed of two feldspar minerals, orthoclase and albite. At first, the two minerals are intermingled. Then, as the newly formed mineral cools, the intergrown orthoclase and albite separate into stacked, alternating layers.

When light falls between these thin, flat layers, it scatters in many directions, producing the phenomenon called adularescence. Adularescence is the light that appears to billow across a gemstone, giving its surface a glowing appearance.

Perhaps the most captivating aspect of adularescence is its appearance of motion. The misty light seems to roll across the gem’s surface as you change the viewing angle.

Other feldspar minerals can also show adularescence. One is a labradorite feldspar found mainly in Labrador, Canada. Another labradorite—found in Madagascar—has a multicolored adularescence over a light bodycolor. It’s known in the trade as rainbow moonstone, despite the fact that it’s actually a variety of labradorite rather than orthoclase.

	A variety of labradorite is sometimes called rainbow moonstone.
Sanidine is another feldspar mineral that can include adularescent gems called moonstones. To be called moonstone, a mineral’s actual identity is not as important as the beauty of its adularescence. @chapter:2 @chapter:0 @chapter:2


# Publication Year: 2024
# Title: Historical Relics Repurposed into Jewelry
# Abstract: Figure 1. An 18K yellow gold and blackened sterling silver shagreen wide cuff bracelet, pendant, earrings, and ring set with antique mother-of-pearl gaming counters. Courtesy of Sarosi by Timeless Gems.
One theme that emerged at the AGTA, GJX, and Pueblo shows was the repurposing of historical artifacts to produce new jewelry items. We saw the incorporation of Chinese, Greek, Viking, and medieval European artifacts into various jewelry pieces at all three shows. Many attendees were drawn to the idea of having a connection to the past in a wearable form.
At GJX, Sarosi by Timeless Gems (Los Angeles) exhibited eye-catching carved mother-of-pearl jewelry (figure 1). While the sheer beauty of the pieces initially caught the authors’ attention, the craftsmanship and story behind them enabled this collection to stand out among a sea of designs. At the center of all the pieces in the collection were hand-engraved mother-of-pearl Chinese gaming counters, once used like modern-day gambling chips. The eighteenth-century counters were commissioned by British royalty and nobility during the Qing Dynasty. Most were engraved on one side with family crests or monograms, with the reverse side illustrating some aspect of Chinese life. The counters were surrounded by a combination of 18K yellow gold, polished sterling silver, and blackened sterling silver, handcrafted by jewelers in Los Angeles to evoke traditional Chinese architecture.

Figure 2. Three ancient artifacts repurposed by Zaffiro. Top left: Medieval silver-gilt strap end from the thirteenth to fifteenth century, set in granulated 22K yellow gold with a 0.07 ct red spinel. Center: Gilded bronze medieval mount from the twelfth to fourteenth century, set in 22K granulated and 18K yellow gold with 0.15 carats of tsavorite garnet and an 11.5 × 14.0 mm black Tahitian pearl. Bottom right: Gilded bronze belt mount from the tenth to twelfth century, set in granulated 22K yellow gold with a 0.13 ct blue sapphire. Photo by Robert Weldon; courtesy of Zaffiro.
In the AGTA designer showroom, Zaffiro (Walla Walla, Washington) devoted a section of their case to their artifact collection, comprising sixth- to fifteenth-century Viking, Anglo-Saxon, and European medieval relics that they incorporated into jewelry (figure 2). These one-of-a-kind pendants integrate actual buried treasure purchased from a reputable auction house in the UK. Zaffiro founders Jack and Elizabeth Gualtieri explained that they like to use items from before the advent of the printing press. Many of the antiquities, originally used to decorate items such as belts, clothing, and horse tack, have retained their original gilding. The Gualtieris set the artifacts in 22K gold frames or rivets and decorate with granulation, sometimes accenting the pieces with colored stones. The appeal of these pieces is in the stories that they tell.
Back at the GJX show, Shans Premier (New York City) offered a large selection of antiquities, including coins in addition to colored stones and jewelry. This multi-generational business has been dealing in antiquities for more than 100 years and in the U.S. for about 40 years. This was their thirtieth year in Tucson. They typically sell more gemstones at U.S. shows, but in Tucson they have a strong following for their antiquities.

Figure 3. A silver Greek Athenian owl tetradrachm from the fifth century BCE weighing approximately 17.2 g with an approximate diameter of 24 mm set in an 18K yellow gold pendant, which cleverly allows the rotation of this coin to face upward on both sides even though the two sides are not stamped in the same orientation. The left image shows the coin obverse with a profile of Athena, and the right image shows the coin tail featuring her patron animal, the owl, which was also a symbol of ancient Athens. Photos by Jennifer Stone-Sundberg; courtesy of Shans Premier.
Sason Shan described a particularly intriguing pendant incorporating one of the most circulated coins from the height of classical Greek civilization: the silver Athenian owl tetradrachm (figure 3). This surprisingly heavy coin was used throughout the ancient world around the time of the Peloponnesian War. Greece minted enormous quantities of these coins using silver from Laurion. Worth several days’ wages, they were too valuable for basic transactions (R.A. Augustin, “Ancient coins – The most famous coin of antiquity – The Athenian owl,” Coin Week, 2022, accessed February 10, 2024, https://coinweek.com/ancient-coins-famous-coin-antiquity/).
With sustainability at the forefront of many consumers’ minds, these upcycled designs extend the life of antiquities, allowing them to be displayed for many years to come. @chapter:25 @chapter:2 @chapter:25


# Publication Year: 1995
# Title: Summer 1995 G&G Lab Notes
# Abstract: Azurite and Antlerite Rock
Diamond with Strain Phantom
Treated-Color Pink Diamond
Unusual Diamond Crystal
Synthetic Diamond Suite
Jadeite Jade with Misleading Inclusions
Omphacite Rock Carving
Cultured Pearl with a Damaged Nucleus
Dyed Quartzite Imitating Jade
Synthetic Ruby with Diffusion-Induced "Fingerprint" Inclusions and Asterism
Cat's-Eye Sapphire
Color-Change Synthetic Sapphire with Twin Lamellae

To view the full section, download the PDF above. @chapter:18 @chapter:1 @chapter:18


# Publication Year: 2014
# Title: Jewelry Shanghai 2014
# Abstract: Figure 1. Top-quality stones, including purple and green jade, were offered at Jewelry Shanghai 2014. Photo by Jennifer Stone-Sundberg.

Organized by the Gems & Jewelry Association of China, Jewelry Shanghai 2014 took place May 8–12 at the Shanghai World Expo Exhibition & Convention Center. The two exposition halls held over 1,000 vendors representing more than 22 countries in 4,200 square meters of exhibitor space. A wide variety was offered, including exceptional examples of tourmaline, jade (figure 1), and ruby, as well as phenomenal stones such as cat’s-eye chrysoberyl and star sapphire. Additionally, superb craftsmanship was on display in the form of fine jade and quartz carvings (figure 2), gold work, and cloisonné enameling. This year saw the addition of top-level fossil, mineral, and gem collector specimens. Other popular items for sale were amber, turquoise, and moonstone.

Figure 2. This clear quartz carving seen at the Shanghai show demonstrates the exceptional craftsmanship sought by Chinese collectors. Photo by Jennifer Stone-Sundberg.
The show featured lectures on topics such as Chinese jade carving, diamond, and Burmese rubies. As Shanghai is China’s diamond import center, the Shanghai Diamond Exchange (which handles every diamond imported into the country) and the Hoge Raad voor Diamant (HRD) were present. Several other gem- and jewelry-related agencies, including the Shanghai Gold Exchange and the International Gemological Institute (IGI), also attended. Mainland China posted jewelry retail sales of 295.9 billion yuan (approximately US$47 billion) in 2013 (http://www.stats.gov.cn/tjsj/zxfb/201401/t20140120_502082.html), and this show certainly indicated the quality and diversity of items the Chinese gem and jewelry market demands today. @chapter:42 @chapter:3 @chapter:42


# Publication Year: -
# Title: Patrick Mohs Jewelry, 2013 JCK Rising Star
# Abstract: View Gallery

Background

	We are Patrick Mohs Jewelry – husband and wife jewelry designers and creators, Patrick Nelson and Mary Kay Mohs. We both grew up in small towns in Minnesota and studied at GIA in Carlsbad, but didn’t cross paths until a few years later. We met in 2005, happy to find out we had so much in common, especially our love for jewelry, gems and design.

	Patrick grew up in his mother’s jewelry store, so he had a fascination with jewelry from a young age.  Mary Kay always admired her mother’s beautiful jewelry and loved learning about rocks and gemstones and how they were formed in the earth. She knew that it was something that she wanted to be a part of.

	Patrick earned his Graduate Gemologist and Graduate Jeweler diplomas in 2000; Mary Kay earned her Graduate Gemologist in 2004.

	We have been married since 2006 and have been designing and making jewelry together ever since. Our studio is in Wayzata, Minnesota, where we bring all of our jewelry to life – from pencil and paper to metal and gemstones.

The Design Process

	It is a constantly evolving tug of war! It all starts with a concept, often taken from nature, then multiple sketches and many variations on paper. From there it’s back and forth between us until we settle on the final design to bring to life in our studio. We continue to make changes until it gets the feel we have in our minds. It has to be just right for both of us – this is our art.

	The look and feel of our jewelry is natural in its flowing lines and movement. Waves are a central theme we are working on. Other themes are natural shapes like volcanos, flowers and snow drifts, along with lakes (we are from Minnesota after all!).

	We are trying to say “explore” with our jewelry, in the hopes of making each piece striking and captivating. We see each design as an adventure we are sharing together. We want to create pieces that make people wonder and make the wearer feel special.

Favorite Gemstones and Metals

	One of our favorite gems is the golden South Sea pearl, which we find to be warm, delightful and unexpected -- especially in contrast to diamonds. We are always on the hunt for unique gemstones – such as Koroit opal, tsavorite, chrysoprase, purple sapphire, kunzite, gem silica – and enjoy contrasting them with another vivid color to bring a piece to life. Color brings a design to life!

	The metal we use the most is 18K yellow gold. We love the richness of its color and the way it contrasts with and highlights many gemstones. We also enjoy exploring with platinum and palladium.

	You can only imagine the “discussions” we’ve had about selecting gemstones since we are business partners, jewelry designers, married and both Graduate Gemologists!

Motivation

	We’re doing what we love and in turn, creating art.  We love having the freedom to challenge what might be the norm, explore what might be possible, and bring to life a vision. Every piece truly is an adventure.

	Mary Kay and Patrick Mohs. Photo provided by Patrick Mohs Jewelry. @chapter:20 @chapter:2 @chapter:20


# Publication Year: 1982
# Title: Tugtupite: A Gemstone from Greenland
# Abstract: The red variety of the mineral tugtupite, a rare silicate closely related to sodalite, has been used as a gemstone since 1965. This article presents the history of the mineral and details of its mineralogy and gemology. A recently discovered light blue variety of tugtupite is also described. Thus far, tugtupite has been found in only two localities: (1) Lovozero, Kola Peninsula, U.S.S.R., where it occurs as very small grains; and (2) Ilimaussaq, South Greenland, where it has been located at several places within the Ilimaussaq intrusion. Gem-quality tugtupite has come almost exclusively from one occurrence, a set of hydrothermal albite veins from the Kvanefjeld plateau in the northwestern corner of the Ilimaussaq intrusion. @chapter:0 @chapter:0 @chapter:0


# Publication Year: 2023
# Title: Heliodor with a Large Schorl Inclusion
# Abstract: Morphological features of the tourmaline crystal included in the heliodor are visible; striations and triangular growth marks are present. A band of fluid inclusions is visible near the tip of the schorl tourmaline. Photomicrograph by Rhiana Elizabeth Henry; field of view 2.90 mm. Gift of Mark Mauthner, GIA Museum no. 37772.
An 8.33 ct long rectangular heliodor, the yellow variety of beryl (ideally Be3Al2Si6O18), was examined by the author. It was reportedly from the Zelatoya Vada mine in Murgab, Tajikistan; however, it was likely from Pakistan (J.S. White, “Let’s get it right: Tajikistan heliodor,” Rocks and Minerals, Vol. 80, No. 4, 2005, pp. 285–286). The heliodor had a large schorl tourmaline inclusion prominently under the table facet (see above) and a small schorl tourmaline near one corner. A thin band of fine fluid inclusions ran parallel to the length of the stone adjacent to the tourmaline. The stone was clearly cut to highlight the interesting inclusion rather than hide or remove it; aside from the two tourmaline inclusions and the thin band of fluids, the beryl had high clarity.
Both the heliodor and the tourmaline were analyzed by Raman spectroscopy and laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) to better understand the structure and chemistry of the minerals. Analyses were conducted on the girdle of the heliodor and on the back end of the tourmaline inclusion where it intersected a pavilion facet. The heliodor had low-moderate water bound in its structural channels, as determined qualitatively by Raman spectroscopy, which is expected for heliodor with low sodium content (R.E. Henry et al., “Crystal-chemical observations and the relation between sodium and H2O in different beryl varieties,” Canadian Mineralogist, Vol. 60, No. 4, 2022, pp. 625–675). The heliodor fit well within the expected chemistry; it had low overall cation substitutions, with minor or trace iron, magnesium, lithium, sodium, and cesium content. The tourmaline was confirmed to be schorl dominant due to its predominant sodium and iron content; however, due to high vacancy at the X structural site, the tourmaline had a high foitite component (D.J. Henry et al., “Nomenclature of the tourmaline-supergroup minerals,” American Mineralogist, Vol. 96, 2011, pp. 895–913).
After data collection for research, this stone will be used in the GIA GemKids program as an educational piece for young students at the Carlsbad campus. It will represent the heliodor variety of beryl, showing fascinating inclusions as well as evidence of LA-ICP-MS laser pits on the girdle of the stone (not shown in the photomicrograph). @chapter:8 @chapter:0 @chapter:8


# Publication Year: 1992
# Title: Natural-Color Nonconductive Gray-to-Blue Diamonds
# Abstract: Two new categories of gray-to-blue diamonds are described. First, two type IIb blue crystals with what appears to be a type IIa outer skin were not electrically conductive in the rough, but conducted electricity once faceted. Second, some non-electrically conductive gray-to-grayish blue diamonds from the Argyle mine, Australia, were determined to be type Ia and to contain unusually high amounts of hydrogen. This latter type of coloration, not previously reported for diamonds, may be due to hydrogen-related defects in the crystal structure. @chapter:29 @chapter:1 @chapter:29


# Publication Year: 2008
# Title: The Color Durability of “Chocolate Pearls” by Ballerina Pearl Co.
# Abstract: Treated-color brown Tahitian cultured pearls, known in the trade as “Chocolate Pearls,” have become increasingly prevalent in the market. As a result, it is important that the durability of the color treatment is well understood. Seven Chocolate Pearls supplied by Ballerina Pearl Co. and 12 untreated Tahitian cultured pearls (for comparison) were exposed to conditions of consumer care and wear—heat, household chemicals, daylight, and some typical cosmetics—to determine their effects on the color. The results were similar for both groups: They did not change color when exposed to daylight, cosmetics, and some chemicals; subtle changes were noticed after exposure to heat; and more significant changes were observed when the samples were exposed to chemically reactive household cleaning solutions. @chapter:53 @chapter:4 @chapter:53