Title: Recycled Gemstones from Perpetuum Jewels Abstract: Figure 1. This 2 ct Old European cut diamond has a color grade of N and a clarity grade of VS1. The faceted girdle is not original to the stone; originally this would have had a bruted girdle. Photo by Albert Salvato, courtesy of Perpetuum Jewels.

The Tucson shows were busy for Perpetuum Jewels (New York and San Francisco), a wholesaler specializing in post-consumer recycled diamonds and colored stones in original, antique cuts. They also work with mine-to-market gemstones and estate jewelry. Co-founder Jared Holstein spoke to us about the importance of recycled gems to the industry (figure 1).
Perpetuum works mainly with designers and jewelry stores in the bridal market. The company originally sought to provide alternatives to newly mined material, focusing on stones cut before 1940. They are active on social media and with organizations such as the Women’s Jewelry Association and Ethical Metalsmiths, which drives traffic their way. Holstein and his partner, Jay Moncada, enjoy working with antique stones because each one is different. Rather than achieving a “mathematical ideal of what a stone should look like,” each is cut to different proportions and has a history and character all of its own. Holstein teaches his clients the progression from the first point cut (with eight facets) to today’s multifaceted cuts. While they have a good deal of stock for center stones, they also have antique melee for eternity bands and other pieces.

	Recycled gemstones from Perpetuum Jewels

Their clients seek the smallest possible environmental footprint—as Holstein points out, “Diamonds are the ultimate recyclable material, because they are so hard,” allowing them to be used in jewelry again and again—or choose, for other reasons, to avoid newly mined gems. Many simply love the appearance and mystique of large antique-cut diamonds. The oldest one in stock was a Peruzzi-cut diamond with a double-cut bottom and a triple-cut top; the diamond came from a Victorian ring that it clearly predated. Diamond’s hardness allows a long journey through many cuts and several mountings. Holstein explained, “I like to think that there is probably a modern brilliant, which was a transitional cut, which was an Old European cut, which was an old cushion, which was a Peruzzi, which was a Mazarin, which was a table cut, and which was a point cut.”

Figure 2. This 3.74 ct unheated sapphire was removed from a vintage 1960s platinum pendant. The sapphire was refaceted by Jean-Noel Soni of Top Notch Faceting. Photo by Albert Salvato, courtesy of Perpetuum Jewels.

Figure 3. This 1.28 ct blue-green sapphire is from Montana’s Eldorado Bar deposit. Photo by Kevin Schumacher, courtesy of Perpetuum Jewels.
With the emergence of the “alternative bridal market,” Holstein and Moncada see designers choosing to work with colored stones instead of diamonds. In these cases, they work with a large supply of corundum. While they carry fine classic and antique blue sapphire (figure 2), their clientele gravitates toward softer blues, teals, and greens (figure 3); Montana and Australian bi- and parti-color sapphire are also popular. Holstein would like to see a move toward spinel and garnets by their bridal clients.
Perpetuum is the only company to achieve the SCS Recycled Gemstone Standard, a third-party certification for 100% post-consumer recycled diamonds and gemstones. The SCS annually audits all aspects of a business to ensure it is a responsible source before awarding this certification. A company must prove, for instance, that its environmental footprint decreases every year while recycled inventory increases annually. The latter has become difficult for Perpetuum, as they now carry recently mined Montana and Australian sapphire to meet their clients’ needs. Doing so has lowered their level of recycled gemstones to below 100%.
Holstein said he has never been able to separate the jewelry pieces he loves from the issues endemic to the industry. He has always been aware that the makings are “from someone else’s backyard.” He considers it his responsibility to engage in ethical, environmentally sustainable and responsible practices because they are better for the communities that mine and cut the metals and stones that help him make a living; this is at the core of his business practices. Perpetuum’s booth in Tucson allows him to meet with new and existing clients and educate them on these matters that are close to his heart. Source: GIA @topic:7


Title: Guizhou Jade from Qinglong, China Abstract: Figure 1. Qinglong, the site of the Guizhou Jade deposit, is located in southwestern China.
A green-blue quartzite produced in the Qinglong antimony deposit, in southwestern Guizhou Province, is called Guizhou Jade in the trade. The source area is located in the middle of the Yunnan-Guizhou Plateau at 25°N latitude, rising 1,600 meters (5,250 ft) above sea level (figure 1). This material was discovered in the 1950s, when the antimony deposit was economically more important to the area. The accompanying blue quartzite was only commercially mined as a decorative material. Later, it was used as a gem material, and it has been popular in Chinese jade markets since about 2011 (figure 2).

Figure 2. This Guizhou Jade ornament, typical in the Chinese jade markets, stands about 11 cm high. Photo by Yushan Dai.
In June 2018, the authors went to the source to inspect the antimony deposit and conduct exploration and collection for Guizhou Jade in the mine. The host rocks are mainly pyroclastic (breccia) rocks, breccia clay rocks of the Dachang layer, and bio-limestones of the Maokou Formation. The Dachang layer is the main ore-bearing layer of the antimony deposit, which is a set of pyroclastic and chemical deposits, and subjected to alteration to siliceous and clay rocks (J.C. Cao, “The dyeing mechanism and cause of Guicui,” Acta Mineralogica Sinica, No. 3, 1983, pp. 183–192).

Figure 3. Left: In the mine, Guizhou Jade is mostly developed in the interlaminar fissures and closely related to stibnite. Right: Guizhou Jade, which develops between layers of stibnite, is massive and can be seen in some small holes in the surface. Photos by Yushan Dai.
The authors observed that in the mine, this material has a close relationship with stibnite. It is mostly developed in the interlayer fissures, fracture zones, and areas where brecciation has taken place. The material occurs as blocks and/or veins (figure 3). In the ores, there are calcite- and gypsum-filled cracks and voids. Green or white clay minerals are often found in the micro-cracks or small holes in the gem material.

Figure 4. The infrared spectrum of a Guizhou Jade sample.
Guizhou Jade is translucent to opaque, with a refractive index of about 1.54 (spot reading), a specific gravity of 2.62, and a Mohs hardness of 6.5–7. According to the infrared spectrum, the main constituent mineral is quartz, and its infrared spectrum matches the α-quartz standard infrared spectrum, including several obvious absorption peaks at 1172, 1124, 1085, 798, 781, 540, and 478 cm–1 (figure 4). Quartzite is generally cryptocrystalline. Its colors range from light green-blue to dark green-blue. The most sought-after color is ocean blue, as shown in figure 2.

Figure 5. The UV-Vis-NIR spectra of both Guizhou Jades show a 415 nm absorption band and a strong absorption band at 590–620 nm.
UV-Vis-NIR absorption spectra (figure 5) of both samples show an obvious 415 nm absorption band and a strong absorption band at 590–620 nm, located in the blue-green range of visible light. The absorption intensity of the light-colored sample is significantly lower than that of the deep-colored sample. The 415 nm absorption band is caused by 4A2g→4T1g transition and 4A2g→4T2g transition of Cr3+. The strong absorption band at 590 to 620 nm is caused by charge transfer between Fe2+→Ti4+ and 4A2g→4T2g transition of Cr3+ (J. Liu, “The color formation of common green quartz jade,” Ming Ri Feng Shang, No. 3, 2017, pp. 368–371).
High-quality Guizhou Jade is rich in color and loved by collectors. It has been widely used in necklaces, bracelets, earrings, and other items. Source: GIA @topic:12


Title: Rare Emerald from China and Pink Sapphire from Sri Lanka Abstract: Figure 1. This 5.06 ct emerald from China’s Yunnan province is one of the finest from this source. Photo by Robert Weldon/GIA, courtesy of 100% Natural Ltd.

	At the AGTA show, David Nassi of 100% Natural Ltd. (New York) showed the authors a 5.06 ct bright yellowish green emerald from China’s southwestern Yunnan province. The stone had some eye-visible inclusions, mainly fissures (figure 1). Other than a few tiny chips along the girdle, the cut gave the emerald a very elegant appearance. Mr. Nassi purchased the stone from a reliable Thai gem dealer who bought it from a Pakistani merchant who obtained it along the China-Pakistan border. Since Mr. Nassi is a cutter who deals with many antique jewelry pieces mounted with stones, he usually recuts stones before selling them. He kept this emerald “as is” due to the superb quality and size for this specific source. The stone was certified by the American Gemological Laboratory as without oil treatment, with China as the country of origin.

	China’s only economically viable emerald deposit is located in Malipo County in Yunnan province. The deposit was first discovered in the early 1990s but has never been extensively prospected or mined. Emerald specimens and crystals are extracted as the byproduct of the tungsten and tin deposit. Geologically, the ore body occurs in a core complex and is related to granitic intrusions in that area. Geochemical studies revealed that the trace element vanadium concentration is about one magnitude higher than that of chromium, indicating that V is the predominant chromophore in Yunnan emerald.

	The size and quality of this emerald are rare for Yunnan. Since the stones contain abundant fissures, most of the production is sold as mineral specimens or ornamental pieces (figure 2). A very small percentage can be faceted for jewelry. As the local government pays more attention to this emerald resource, new development and further exploration are expected.

Figure 2. Due to the fissures in Chinese emerald, stones are usually marketed as mineral specimens. This emerald crystal is still in the matrix. Courtesy of Yunnan Emerald Magazine.

	Mr. Nassi also showed us an intensely saturated 24.69 ct Sri Lankan pink sapphire (figure 3), from a necklace he had obtained from another estate jewelry dealer. Although the necklace itself was unattractive, Mr. Nassi immediately saw potential in the sapphire. He estimated the weight of the mounted stone and made an offer to buy the necklace. The stone, which was abraded with multiple scratches, lost two carats in its recutting but showed a dramatic improvement.

Figure 3. This 24.59 ct Sri Lankan pink sapphire was removed from an estate necklace and recut to bring out its full potential. Photo by Robert Weldon/GIA, courtesy of 100% Natural Ltd. Source: GIA @topic:1


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. Source: GIA @topic:7


Title: Exhibition Review: Spectaculaire Second Empire Abstract: Figure 1. Gold bracelet, enamel, natural pearls and citrine, Mellerio dits Meller, ca. 1870. Mellerio collection, Paris. Photo courtesy of Mellerio dits Meller.

France’s Second Empire lasted less than 20 years, from 1851 to 1870, between the Second and Third Republics. Louis Napoléon Bonaparte, the first president of the French Republic, could not seek another mandate. On December 2, 1851, after a military coup, he dismissed the National Assembly, and a year later he named himself Napoleon III, head of France’s Second Empire.  Paris’ Orsay Museum has developed an exhibition, Spectaculaire Second Empire, showing how crucial these years of social disruption and economic euphoria were for France. Often linked to imperial celebrations, this period is typically described as decadent. But it was a time of crisis, when moral and aesthetic habits changed and an old way of life was faced with major technological change, expanded public infrastructure such as railways and inland waterways, and growing industrial activity. The exhibition displays notable relics to reflect the era, including artwork, furniture, and jewelry (figure 1).
During this period many modest craft workshops became factories for luxury goods, including jewelry and objets d’art, as the French imperial family ordered interior design embellishments to enhance homes. Aristide Boucicaut created the first modern department store, Le Bon Marché, in 1852. Sophisticated women changed their dresses and jewels many times a day to avoid wearing the same outfit twice. The dress ball in the northern town of Compiègne became one of the best places to admire the latest creations from jewelers and dress tailors, marking the beginning of high fashion as we know today.

Today only three of the jewelry houses that thrived during the Second Empire continue to produce fine jewelry. Of these three, the museum has chosen to exhibit the work of Mellerio dits Meller, along with pieces by jeweler Alexandre-Gabriel Lemonnier. Napoleon III appointed both Lemmonier and the House of Mellerio crown jewelers; the emperor had become familiar with their talents after they displayed at the Great Exhibition of 1851 in London (also known as the Crystal Palace Exhibition).

Alexandre-Gabriel Lemonnier (1808–1894) was employed by the Bury jewelry shop before opening his own business. Thanks in part to the sponsorship of then-President Bonaparte, Lemonnier opened a more prominent Parisian workshop on Place Vendôme, first at No. 6 and later at No. 25 (a location that is currently occupied by Bulgari) and had clients such as Queen Isabella II of Spain and the Demidoff family of Russia. Among his creations, an impressive diadem with “La Regente” featuring a 337-grain natural pearl now preserved in a private collection. His company closed after the Franco-Prussian War, and he died in 1884. It is exceptional to see pieces he designed on display, particularly the diadem and crown that both belonged to Napoleon III’s wife, Empress Eugénie (figure 2, left and right).

Figure 2. Left: Crown of Empress Eugenie, by Alexandre-Gabriel Lemmonier, 1855. Leather, diamonds, emeralds, and gold. Gift of Mr. and Mrs. Roberto Polo, 1988, inv. OA 11160 © RMN-Grand Palais, Louvre Museum/Pierre and Maurice Chuzeville. Right: Diadem of Empress Eugenie, by Alexandre-Gabriel Lemmonier, 1853. Silver, gold, diamonds, and natural pearls. Gift of the Friends of the Louvre, 1992, inv. OA 11369 © RMN-Grand Palais, Louvre Museum
The Italian Mellerio family first arrived in France in 1515; in 1613 Queen Marie de Medici granted the jewelers the right to trade without the customary administrative restrictions. Prior to the French Revolution of 1789, Marie Antoinette and her friends became regular customers. In 1815, Mellerio became the first jewelry store on the Rue de La Paix. During the Second Empire, the House of Mellerio displayed their creations in many “Expositions Universelles,” highlighting technical and artistic innovations such as flexible gold wires used to give stones an oscillating movement (patented in 1854) and colorful enamels.

Nature is one of Mellerio’s favorite inspirational sources: roses, oak leaf, olive leaf, chestnuts. One example is a gold and silver rose brooch set with diamonds that Princess Mathilde ordered in 1864. Perhaps one of the most impressive pieces is the lilac brooch (figure 3) first displayed during the 1862 Exposition Universelle. Handmade with enameled gold and diamonds, its realistic appearance cannot leave anyone indifferent to its artistic brilliance.

Figure 3. “Broche fleur de lilas,” Mellerio dits Meller, 1862. Green, pink and violet enameled
gold, and diamonds. Private collection. Photo courtesy of Wartski, © Wartski Ltd., London.
Another innovation was transformable jewelry to be worn for different occasions. Mellerio introduced this technique in 1830, and it has been used by jewelers ever since. Tiaras can be transformed into pendants, bracelets, necklaces, or brooches. The exhibition displays a gold diadem composed of eight brooches set with turquoise and diamonds. Mellerio also created flexible snake bracelets to be worn around the wrist or arm. Princess Mathilde ordered many of these pieces symbolizing life and death, force and purity. The enameled gold bracelets set with diamond, emerald, and ruby (figure 4) also introduce another of Mellerio’s favorite inspirations: archaeological discoveries.

Figure 4. Serpent bracelets, Mellerio dits Meller, ca. 1860. Gold, enamel, diamonds,
rubies and emerald., Mellerio collection, Paris. Courtesy of Mellerio dits Meller.
Along with nature- and archaeology-inspired pieces, the house is also familiar with Gothic revival jewelry. Mellerio family members traveled to Rome several times a year in search of the best craftsmen to create cameos or micro-mosaics. Many patterns between 1850 and 1870 were influenced by Egyptian, Greco-Roman, Byzantine, and Paleo-Christian styles. This scarab pendant/brooch shown in figure 5 is set with Burmese rubies from Mogok and natural abalone pearl. The Gothic revival style, seen throughout the 19th century, was especially linked to romanticism, the Middle Ages, and Renaissance rediscovery. A perfect example is the transformable enameled gold bracelet with natural pearls and citrine seen in figure 1.

Figure 5. Scarab brooch/pendant, Mellerio dits Meller, ca. 1865. Silver, pink gold, abalone pearl, diamonds, and Burmese rubies from Mogok. Private collection. Photo courtesy of Mellerio dits Meller.
The most amazing piece in the exhibition may be a transformable peacock feather brooch (figure 6) crafted by Mellerio master jeweler Henri Foullé. Empress Eugénie commissioned this piece after the original, shown at the 1867 Exposition Universelle, was bought by Duchess Medina Coeli. The emerald—Eugénie’s favorite gemstone—can be removed to become a pendant, and the brooch itself is said to protect its wearer.

Figure 6.“Plume de Paon” silver and gold transformable brooch, Mellerio dits Meller,
1868. Diamonds, rubies, sapphires and emeralds. Mellerio collection, Paris. Courtesy
of Mellerio dits Meller.
Spectaculaire Second Empire at the Orsay Museum runs from September 27, 2016, through January 15, 2017. The recommended admission fee is 12€ for adults, and children under 18 are free; admission is free on the first Sunday of the month. The museum is open Tuesday to Sunday from 9:30 a.m. to 6:00 p.m. and Thursdays from 9:30 a.m. to 9:15 p.m. It is closed on Mondays and on Christmas Day. Source: GIA @topic:6


Title: The Beauty of Birthstones Connects Us All Abstract: The birthstone for August is peridot.

                      We all have one. What’s yours?

We’re talking birthstones here and GIA is showcasing them in a big way through spring 2013 at the Carlsbad campus. The GIA Museum team decided to focus on birthstones because people connect with them as they search for the gem that represents their birth date.

“Birthstones are a fun, popular and colorful area of gemology and resonate with all audiences regardless of gender, age, nationality or religion,” said Terri Ottaway, curator of the GIA Museum. “The lore, origins, attributes and characteristics associated with various gems are educational and hold universal appeal for all of us.”

“GIA Celebrates Birthstones” contains more than 250 objects from around the world, including gemstones, minerals and jewelry pieces. Each month of the year and its birthstone is represented, along with fun facts about the gems. For example, did you know that garnets can be green, topaz can be blue and sapphires can be pink? Or that ancient people believed wearing amethyst would keep them sober, while emeralds were thought to have healing properties for the eyes?

Here are some more traits associated with modern-day birthstones:

January: garnet/calm
February: amethyst/power
March: aquamarine/unity
April: diamond/endurance
May: emerald/joy
June: pearls/clarity
July: ruby/harmony
August: peridot/purity
September: sapphire/loyalty
October: opal/hope and tourmaline/strength
November: topaz/prosperity and citrine/awareness
December: turquoise/peace and tanzanite/balance

Why do some months have more than one birthstone? Different traditions are often cited, but the most significant reason is that some gemstones are too rare and expensive to be attainable for a majority of people, and others just aren’t that popular. Source: GIA @topic:7


Title: Ancient Tourmaline and Beryl from Afghanistan Abstract: This 9.52 ct pink tourmaline is part of an extensive private collection of ornaments claimed to be from ancient Afghanistan. Photo by Jaroslav Hyršl.

              A large private collection of beads and carvings from antique excavations, assembled in the 1970s by a collector in Afghanistan, was recently examined. The pieces were claimed to be found near the ancient city of Bactra (modern-day Balkh), 300 km northwest of Kabul near the border with Uzbekistan. Bactra was a center of the Bactrian civilization, which flourished from 2500 to 1500 BC. The collection contains several thousand drilled beads, mostly agate, carnelian, and rare blue chalcedony. The next most abundant materials are turquoise—some as small as 1 mm in diameter—and lapis lazuli. Less common are garnet (two types of almandine), rock crystal, amethyst, serpentinite, and steatite, as well as organic materials identified as amber, pearl, and mother-of-pearl. Other very interesting finds are treated rock crystal and milky quartz, both containing blue glass spots on their surfaces, similar to medieval sapphire imitations (Fall 2001 GNI, pp. 243–245).

The two most interesting pieces, a pink bird (above) and a very pale blue bead (below), were studied in detail. The bird had a light green bottom section, measured 13.9 × 13.6 × 7.6 mm, and weighed 9.52 ct, with a refractive index close to 1.63. It was strongly pleochroic (pink and colorless), and it was uniaxial negative in a conoscope. In both short- and long-wave UV light the center was inert, but a thin triangular zone of light blue fluorescence was visible near the surface. These tests confirmed the stone’s identification as tourmaline. It was originally a “watermelon” tourmaline, pink with a green rim, but only a small part of the green rim had been preserved.

	This aquamarine bead, reported to be from Afghanistan, weighs 20.28 ct and is likely one of the oldest of its kind. Photo by Jaroslav Hyršl.
The pale blue bead was set in a heavily corroded metal, probably bronze. The entire piece measured 20.7 × 12.3 × 6.7 mm and weighed 20.28 ct, with an RI close to 1.59. The stone was weakly pleochroic (very light blue and colorless), inert in UV light, and uniaxial negative in a conoscope. These results indicated a very pale aquamarine. The identification of both beads was confirmed by their Raman patterns, collected by A. Gilg (Technical University of Munich).

Both beads are possibly among the oldest of their kind. Large and historically significant rubellites have been reported from the 14th and 16th centuries, and a single beryl bead from Nubia has been dated back to Predynastic time (before 3200 BC), but few details are known. The first beryl locality of significance was reportedly the Egyptian emerald deposit exploited as early as the Ptolemaic era (after 332 BC).

Both tourmaline and aquamarine are typical pegmatite minerals. Gem-bearing pegmatites have been mined since the 1970s in the Nuristan province of eastern Afghanistan and northern Pakistan—the possible origin of both beads. Source: GIA @topic:1


Title: Corundum Source Types Abstract: GIA Identification and Origin Reports for ruby and sapphire include an opinion on the geographic origin of the stone, if determinable. The chart below and the downloadable PDF include more information about corundum sources and GIA’s source type classification system, detailing the relationship between source type and geographic origin.

	This information was included with GIA Corundum Reports (now GIA Identification and Origin Reports for ruby and sapphire reports) until March 2013. Source: GIA @topic:1


Title: De Beers Optimistic as Sales Revive; Luxury Houses Remain Cautious Abstract: De Beers and Alrosa sold more than $1 billion into the rough market in January, the largest monthly quantity in three years. These rough diamonds – from Brauna, Nordestina City, Brazil – have a total weight of 62.78 carats. Courtesy Aftergut N. & Zonen. Photo by Robert Weldon/GIA

	De Beers issued a dose of optimism recently with its largest cycle (sight) in more than two years. Additionally, luxury sales have begun to rise again, albeit hesitantly, after a negative year.

	The company’s January cycle totaled about $720 million and the Feb. 20-23 cycle is expected to be similar.

	De Beers CEO Bruce Cleaver said demand for rough diamonds remained “healthy,” adding that the company would exercise caution if necessary, especially at the lower end of the market where Indian manufacturers are still trying to adjust to the demonetization of 500 and 1000 rupee notes (worth US $7.50 and $15 respectively) which hit some of the smaller firms that deal mainly in cash.

	While rough demand remains firm, inventories of polished diamonds have been increasing as sales have not kept pace with production of new goods. This is creating concern that the trade may encounter difficulties in the second half of the year.

	Alrosa, which mines and markets the majority of Russia’s diamond production, sold $358.2 million in rough diamonds at its January sale. The company expressed caution, especially for melee goods that have been affected by India’s demonetization.

	The large luxury houses – including LVMH, which owns the majority of shares in De Beers’ retail operations, Italian jewelry brand Bulgari, and Fred Joallier − posted a 5% worldwide sales increase for the year, with an especially strong final quarter.

	LVMH chairman Bernard Arnault warned against “irrational exuberance” as the company’s stock climbed about 10% in the final quarter, saying potential trade and currency wars and continued difficulties in Europe − coupled with the fact that the world is coming to the end of a 10-year growth cycle − could bring “difficult trading conditions” during the second half of the year. LVMH noted it would mount a strong marketing push to counteract this challenging economic and geopolitical environment in 2017.

	Richemont, which owns Cartier and Van Cleef & Arpels, had an 8% sales increase in its jewelry division during the first fiscal quarter of 2017, after a 13% decline for fiscal 2016 that ended Sept. 30. While improved business in the Chinese mainland was one factor for the upturn, strong demand from upscale U.S. consumers also accounted for a significant portion of the increase. Source: GIA @topic:8


Title: The Sinkankas Library Abstract: The world-renowned Sinkankas collection of books and other publications is now available to the public as part of the Richard T. Liddicoat Gemological Library and Information Center at GIA Santa Monica. Acquired by noted author and lapidary John Sinkankas and his wife Marjorie over the course of 40 years, the approximately 14,000 items include virtually all of the major works related to the study of gems and jewelry. This review of the important works in the Sinkankas library also serves to highlight the historical development of gemology – in art, in culture, and as a science. Source: GIA @topic:10


Title: Dumortierite In Rock Crystal Quartz Abstract: Figure 1. This group of rock crystal quartz from Brazil shows vibrant blue dumortierite inclusions. The largest rough crystal weighs 139.79 ct, and the faceted stone weighs 15.47 ct. Photo by Kevin Schumacher.

              Dumortierite, which commonly occurs as a blue borosilicate mineral, is of gemological interest when present in quartzite, making an attractive blue ornamental material. Recently examined by GIA’s Carlsbad laboratory were several examples of dumortierite inclusions in rock crystal quartz (figure 1) provided by Luciana Barbosa (Asheville, North Carolina). According to Mrs. Barbosa, the material is reported to be from the Brazilian state of Bahia, in the Serra do Espinhaço Range near the Vaca Morta quarry.

Figure 2. Clusters of vibrant blue acicular dumortierite were observed in this rock crystal quartz. Note that some dumortierite crystals are brownish due to epigenetic mineral staining along the interface of the quartz host and the dumortierite inclusions. Photomicrograph by Nathan Renfro; horizontal field of view 7.38 mm.
Much of the material examined by the authors showed phantom planes and clusters of acicular needles with a vibrant blue coloration (figure 2). Polarized light revealed very strong blue to colorless pleochroism in the blue mineral inclusions. Raman analysis confirmed the identity of the needles as dumortierite. Also observed in one sample were colorless acicular crystals on a phantom plane, which were also identified by Raman as dumortierite (figure 3).

Figure 3. Unusual pale blue to colorless needles of dumortierite were also observed in the rock crystal quartz. Photomicrograph by Nathan Renfro; horizontal field of view 2.24 mm.
Blue color in dumortierite has previously been reported to be caused mainly by Fe2+-Ti4+ charge-transfer (see http://minerals.gps.caltech.edu/FILES/Visible/dumortierite/Index.htm). The chemical composition of the blue and colorless dumortierite inclusions was analyzed by LA-ICP-MS to look for any prominent differences that might explain the variance in observed color. The most significant difference was in the magnesium content, which was almost 10 times higher in the colorless dumortierite inclusions (1070 ppma, compared to 127 ppma Mg in the blue dumortierite). While more research is needed to fully understand the role this higher magnesium content has on color, the authors speculate that the titanium preferentially charge-compensates with magnesium instead of iron. If there is not enough excess titanium relative to magnesium, it may not be possible for titanium to pair with divalent iron, and this would prevent the formation of blue color.

These are the first examples of prismatic blue and colorless dumortierite inclusions in rock crystal quartz we have encountered. Source: GIA @topic:2


Title: Jade Description Abstract: Jadeite jade, often cut as a cabochon, is one of the most valuable and culturally significant gemstones. - Courtesy Mason-Kay Fine Jade Jewelry

Among gemologists, jadeite and nephrite have long been considered the materials that may be referred to as jade. More recently some green omphacite has also been included in the definition. These are actually metamorphic rocks made up of tiny interlocking mineral crystals which make the gems exceptionally tough.

Jadeite can be semi-transparent to opaque and comes in a wide range of attractive colors: many shades of green, yellow, and reddish orange, plus white, gray, black, brown, and lavender (often a light purple or light grayish violet). The coloration is often unevenly distributed, giving jadeite an interesting visual texture carvers use to create imaginative and intriguing effects.

Nephrite ranges from translucent to opaque and can be light to dark green, yellow, brown, black, gray, or white. Its colors tend to be more muted than jadeite.

Jadeite jade comes in a variety of colors. Green is the most valuable. - Courtesy Mason-Kay Fine Jade Jewelry
Omphacite has typically been thought of as dark green to black. However, some green omphacite has been seen in the GIA laboratory that not only has a similar color to fine green jadeite but also has the same gemological properties as jadeite. Omphacite can be identified by its Raman spectra, which requires advanced testing techniques.

Modern gemologists use the word “jade” as a generic term for nephrite, jadeite, and under certain conditions green omphacite. “Fei Cui” is a traditional Chinese term for jadeite jade but is not universally accepted. Today the term is used in many places in Asia to refer to several materials including jadeite, kosmochlor and omphacite.

Rough jadeite jade often takes the form of boulders. This one from Myanmar weighs 23 metric tons.
These gems have been linked throughout history. In fact, the term jade has sometimes been erroneously applied to a number of gems and ornamental materials resembling jade, and even some manmade equivalents. Source: GIA @topic:12


Title: James Shigley Abstract: The Face of GIA Research

For almost 40 years, Dr. James Shigley has been widely recognized as the face of GIA research. Since 1982, he has represented the Institute around the world, lecturing and publishing extensively on topics related to diamonds, colored stones, and gem identification.

After graduating from the University of California, Berkeley, Shigley served on active duty in the U.S. Army from 1971 to 76, eventually retiring from the Army Reserve as a lieutenant colonel. He joined GIA as a senior research scientist after earning a doctorate in geology from Stanford University. He quickly proved his mettle in the laboratory, becoming manager of the research department within three years of his arrival. In 1987, he became GIA’s director of research; today, he serves as the Institute’s first and only distinguished research fellow.

Shigley has been a prolific contributor to gemological research. As of September 2014, he has authored or coauthored 59 articles for Gems & Gemology alone; 29 of those have received the journal’s Most Valuable Article award. He serves as a contributing editor for G&G, and as the editor of the G&G in Review book series. His studies have identified methods of separating natural from synthetic diamonds, documented important gem localities, and established characteristics of HPHT synthetic diamonds. Shigley was instrumental to the creation of the GIA Gem Project, a collection of 2,800 stones (representing 225 minerals) from the Edward J. Gübelin Collection that is available as a free research and identification resource to the trade and the public.

Shigley has mentored countless GIA staff members during his 32-year tenure, passing the torch of practical skills and hard-won experience to the next generation of gemologists. His contributions have earned industry recognition, including AGA’s Antonio Bonnano Award for Excellence in Gemology (2007) and GIA’s Staff of the Year award (2006). Jim Shigley’s work has solidified the Institute’s reputation for groundbreaking research. Source: GIA @topic:7


Title: Aquamarine Quality Factors Abstract: This 3.74-ct. princess-cut aquamarine’s prized medium-blue color is highlighted by the 22 diamonds that surround it. The ring is an original, copyrighted design by Zoltan David. - Robert Weldon, courtesy of Nancy's Collection

                      In the commercial market, aquamarine competes with treated blue topaz for attention, but fine aquamarine sells for far more than equivalent-quality treated blue topaz.

Color
Aquamarine’s color range is very narrow: It can be blue, very slightly greenish blue, greenish blue, very strongly greenish blue, or green-blue. The gem’s most valuable color is a dark blue to slightly greenish blue with moderately strong intensity. In general, the purer and more intense the blue color, the more valuable the stone. Most aquamarine is a light greenish blue.

	This superb 32.10-carat heart-shaped Brazilian aquamarine shows the gem's finest color, a moderately strong, medium-dark, very slightly greenish blue. - Courtesy M.Chung Gemstones and Fine Jewelry Co.
Although some buyers prefer the more greenish natural color, most of the aquamarine in the market was heat-treated to give it more of a pure blue.

Fashioned aquamarines often have to be fairly large—generally over 5 carats—to show intense, dark color. Although small gems are rarely saturated enough to be attractive, stones from some mines in Africa—Nigeria, Madagascar, and Mozambique, for example—are known for intense color in sizes under 5 carats. For this reason, smaller, top-color stones might sell for more per carat than larger stones of the same color.

Clarity
Most faceted aquamarines are eye-clean. Some crystals might contain liquid inclusions, but clarity characteristics are few or absent in most finished gems. Stones with eye-visible inclusions are usually fashioned into cabochons, beads, or carvings.

	Carvings are popular for translucent to opaque aquamarine. - Courtesy Neoart Peru

	Faceted aquamarine usually has no eye-visible inclusions. - Courtesy Dudley Blauwet
In some beryl crystals, there are enough parallel inclusions—usually long hollow or liquid-filled tubes—to allow cutters to fashion the rough to show a cat’s-eye.

	This very greenish aquamarine cabochon has enough parallel inclusions to display a cat’s-eye.
Cut
Aquamarines can be cut into almost any shape, but cutters often fashion them as emerald cuts or as round or oval brilliants. The rough is fairly plentiful, so well-cut stones are fairly common. The gemstone’s hardness and transparency make it popular with designers, artists, and carvers. Gem sculptors use aquamarine for fantasy cuts and ornamental objects.

	Aquamarine can be cut in a variety of standard shapes.

	Emerald cuts are among the common aquamarine cutting styles. - Courtesy ICA
The gem is pleochroic, which means it shows different colors in different crystal directions—in the case of aquamarine, they’re near-colorless and strong blue. Fortunately, the blue pleochroic color corresponds with the cutting orientation that retains the most weight, with the table facet aligned parallel to the length of the crystal.

	Aquamarine is a great medium for artistic designer cuts like this 10.37-carat beauty. - Lydia Dyer, gem courtesy John Dyer & Co.

	Aquamarine that’s too included for faceting is often carved and set into designer jewelry. - © GIA and Tino Hammid
Carat Weight
Aquamarine crystals come in sizes from very small to very large—some even up to 100 lbs. (45 kg). While large stones are readily available, it’s difficult to use them in jewelry, so there’s less demand for them, except as center stones. As a result, per-carat prices tend to decrease for sizes above 25 carats.

Many very large aquamarine crystals have been discovered. The largest Brazilian aquamarine on record was found in 1910, in Minas Gerais, Brazil. It weighed 244 lbs. (110 kg) and measured 19 in. (48 cm) long and 15 in. (38 cm) in diameter. Source: GIA @topic:1


Title: De Beers’ Sight: Recovery or Overload? Abstract: De Beers’ CEO Phillipe Mellier noted that demand for both rough  and polished diamonds has improved. The company released its largest sight in many months in April, citing the upturn. Photo by Robert Weldon/GIA

	De Beers reportedly raised rough diamond prices by an average of 2% at its April 4-8 sight cycle. The $660 million total announced by De Beers was larger than expected.

	The price increase caused some concern in the market from manufacturers who have just begun to return to profit after nearly two years of struggle. Since there have been no reports of clients refusing goods as they did last year, however, most were still on the profitable side and have accepted the deals.

	De Beers’ CEO Philippe Mellier said polished diamond demand has been reasonably positive at the wholesale level and that “rough demand is significantly stronger” than last year. He hinted that the May 16-20 cycle will be smaller because seasonal demand usually declines mid-year.

	Alrosa announced it was sitting on a 22 million carat (valued at $2.5 billion) stockpile of rough left from last year, when it cut back sales by nearly 25%. The company will reduce its mining output this year by 5% to 7%, but noted that it sold $780 million worth of rough in January and February, slightly less than De Beers by value.

	Some analysts worry that De Beers and Alrosa may be compromising the recovering market by selling more rough than world demand warrants.

	In addition, the credit situation in the diamond industry continues to tighten even as the trade recovers from the difficulties of last year. Bankers − and most diamond people − acknowledge that the recovery is fragile, based on a reduction of excess inventory and firming polished prices.

	This week, Standard Chartered Bank, which holds about $2 billion in loans to the industry (about 12% of the industry’s total outstanding credit), reportedly informed its clients that they would have to provide collateral for 100% of their outstanding loans or obtain payment insurance for their outstanding balances. The bank said it will not accept receivables as collateral as it (and other banks) had done in the past.

	Standard Chartered blamed its action on an increased regulatory and compliance environment, but the bank has been struggling with non-performing loans across the board, particularly in commodities – especially oil and gas – that have fallen sharply in price since the China bubble burst. Bloomberg reported that the bank is trying to shed or restructure about 40% of its $261 billion loan portfolio. The new CEO also replaced all of the bank’s senior managers.

	The presidents of the Israel Diamond Exchange and International Diamond Manufacturers Association both called for a concerted action to lobby industry lenders to ease credit restrictions at the upcoming World Diamond Congress in May.

	China’s largest jewelry retailer, Chow Tai Fook, reported continued declines in sales, both in Hong Kong and the Mainland. The company said same store sales were down 26% for the quarter that ended March 31, compared to the same period last year.

	COLORED STONES

	Gemfields reports that its April auction of quality emerald rough achieved near record prices: 469,000 carats sold for $33 million or about $70.68 per carat.

	CEO Ian Harebottle said the company was shifting its marketing strategy to get closer to retail markets. It did not renew the three-year contract with actress Mila Kunis, who it previously featured in its advertising. The company is putting that money into partnering with top retailers, such as Bergdorf Goodman in the U.S., to promote emerald and ruby jewelry, much of it under the Faberge brand it acquired two years ago.

	The company earned $12.3 million on revenues of $171.4 million in 2015, selling 30.1 million carats of emeralds from its Kagem mine and 8.4 million carats of ruby from its Montepuez mine. Harebottle said the company is committing 20% of its revenues to growing demand, 11% on advertising, and 9% on exploration, with projects in Colombia, Sri Lanka, Madagascar and Ethiopia.

	AUCTIONS

	This spring auctions will bring potentially record-breaking sales of fancy colored diamonds and a major ruby to market.

	On April 20 in New York, Christies will offer the 15.99 ct. Jubilee Ruby set by Verdura and a 10.07 ct. Fancy Intense purple pink diamond, graded by GIA. On May 18 in Geneva, Christie’s will auction the 14.62 ct. Fancy Vivid Blue Oppenheimer diamond, which is expected to bring $38 to $45 million.

	Sotheby’s Geneva auction on May 17 will offer the “Unique Pink” a 15.38 ct. GIA-graded Fancy Vivid pink diamond, which is expected to sell for $28 to $38 million. And, earlier this month, the 10.1 ct. De Beers Millennium 4 Fancy Vivid blue diamond brought $3.1 million per carat ($31.8 million total) at Sotheby’s Hong Kong sale. The same sale brought a $2.47 million price for a Fancy Vivid orange diamond and a similar price for an imperial jadeite ring with matching earrings. Source: GIA @topic:8


Title: Market Reaction to the Pandemic: Insights from Exhibitors Abstract: Figure 1. The majority of the 35 exhibitors surveyed have a small-scale business and more than 20 years in the industry.
When COVID-19 evolved from a regional crisis to a global pandemic, the gem and jewelry trade abruptly paused for a short period and then gradually recovered to the pre-pandemic level. To investigate the trade’s reaction, the impact on business, and market trends over the past two years, the authors took advantage of the Tucson show to survey the exhibitors.
This brief report presents outcomes from written surveys conducted with 35 randomly selected AGTA and GJX show exhibitors. The survey consists of two portions: general information about the business, and six pandemic- and market trend-related questions. All 35 exhibitors based their responses on their own experiences, with a very limited number of “not applicable” answers that were not included in the findings.
Nearly all respondents identified themselves as wholesalers, with a couple of exceptions as designers or miners. The authors noticed that some exhibitors played multiple roles: wholesaler, retailer, and sometimes even designer. While traditional roles in the gem and jewelry industry still carry on, the boundaries between them have become blurred. More than 70% of the exhibitors surveyed have fewer than 10 employees, and 85% of them are industry veterans with more than 20 years’ experience in the trade (figure 1). Although the pool is small, it aptly reflects the nature of the gem and jewelry business in general, with small-scale business as the majority, but often with generations of commitment to the industry.
When asked about the impact of the pandemic on their business, most responded that it was most impactful at the beginning of the crisis, but recovery has been quite smooth since then. Some did express concern about the post-pandemic supply issues. Two-thirds of the interviewees stated that more business shifted online over the past two years, resulting in marketing and selling strategy changes (figure 2). Notably, the relatively new businesses, many with less than five years in the trade, often started with more business online than offline. Though sellers mostly embraced online trading of gems and jewelry, some had difficulties capitalizing on it, particularly with colored stones since buyers still prefer to check the quality in person.

Figure 2. Due to mobility restrictions caused by the pandemic, most companies have shifted at least some business online to adapt to the new normal. This often required changes in sourcing, marketing, and selling strategies.
To investigate the types of stone and jewelry sales over the past two years, the authors asked the selected exhibitors to circle the corresponding items, with many circling multiple answers in each category. These questions covered gemstone species, jewelry, precious metal, and pearl types, with the understanding that while diamond sales continue to dominate the market, they are not the focus for the exhibitors surveyed. Not surprisingly, the “big three” still dominate sales, with sapphire leading the trend (figure 3, top), and tourmaline and spinel immediately following the big three. As for jewelry types, rings and earrings lead the way (figure 3, middle). Yellow gold still sells the best, with platinum as the second best seller (figure 3, bottom). Several pearl dealers circled their best sellers, but the authors found that overall sales were quite evenly distributed among the four major cultured pearl types.

Figure 3. The best sellers over the past two years during the pandemic, according to gemstone species, jewelry type, and precious metal type.
As traceability is a hot topic in the trade, the authors also asked two related questions about whether respondents noticed increased consumer concern on traceability. If they answered yes, they were asked whether it affected how they do business. The result shows that about two-thirds of them noticed the concern, and two-thirds of those who noticed the concern did not feel that it affected their business (figure 4).

Figure 4. Many of the exhibitors surveyed noticed an increase in consumer concern about traceability, but the majority of them said it does not impact their business.
As the world enters the post-pandemic era, it is worthwhile to continue monitoring how the market reacts to the changes and how tradespeople adapt to the new normal. Source: GIA @topic:8


Title: De Beers’ Sight Highlights Market Disarray Abstract: Many diamond dealers are facing high rough inventories in all sizes and qualities, except the largest goods. Some estimates place the stock overhang at three to four months. Photo by Robert Weldon/GIA

	De Beers’ Oct. 5-8 sight was estimated at between $250 million and $400 million, but that figure is complicated by a significant percentage of refusals and, reportedly, discounted side deals the company made with several large clients shortly beforehand.

	While the sight disappointed most De Beers’ sightholders, who were expecting further cuts in prices (they wanted at least 10% across the board), a core group of clients holding huge inventories opposed any price cuts out of fear of devaluing their stocks. There was little consensus regarding the original allocation totals once the sight was over, and agreement only that most manufacturers had little appetite for rough that could not be cut profitably. Dealers were also reportedly unhappy over reports that De Beers had sold previously refused goods to certain clients at reduced prices.

	The issue most dealers are facing is high rough inventories in all sizes and qualities, except the largest goods. Some estimates place the stock overhang at three to four months.

	This was the final De Beers’ sight for goods destined to be sold for Christmas. The Nov. 2-6 sight occurs just on the eve of India’s Diwali festival, when diamond companies traditionally close for two or three weeks. Analysts expect many Indian diamond operations to remain closed after Diwali, potentially through the rest of the year.

	De Beers has sold 26% fewer diamonds into the market during the first half of 2015, compared to the same period last year, and will likely end the year selling about 28 million carats, nearly 5 million down from last year’s total of 32.7 million carats.

	Alrosa, the Russian producer that is the world’s largest by volume, said its first half sales this year totaled just under 18 million carats with revenues of $2.1 billion, which is close to last year’s results. The company said, however, that revenues will likely fall short of that total in the second half because of the September price cuts and a provision that allows clients to refuse or defer purchases.

	Alrosa sells the vast majority of its production – 38.3 million carats last year – in regular sales similar to De Beers’ sights, through contracted sales and tenders.

	The Russian company’s sales last year totaled $3.7 billion, but because of the diamond market difficulties, the company sold just over $232 million to Gokhran, the Russian government stockpiling agency, instead of selling into the market. Gokhran, in turn, holds periodic auctions of its diamond stocks.

AUCTIONS

	Both Christie’s and Sotheby’s reported that the market remains robust for ultra-high-end jewels as the fall season got under way.

	One lot in Sotheby’s Oct. 7 Hong Kong auction set a record: A 27.68 carat (ct.) Kashmir sapphire achieved a record per-carat price $242,145 ($6.7 million total). Two other top lots included a natural gray pearl necklace that sold for $5.26 million and the Viscountess Harcourt Diamond Necklace, produced by Tiffany & Co. in the 1880s, went back to Tiffany for $1.55 million.

	First half jewelry sales for Christies ($313.2 million) and Sotheby’s ($286 million) were a little short of last year’s pace. Looking at the pre-sale estimates, expectations for top stones have eased from last year’s record prices ($120,000 to $130,000 per carat for large D flawless, compared to $140,000 to $160,000 last year). However, last year saw some ultra-extraordinary pieces come up for auction.

	On Nov. 10, Christie’s will auction a 16.08 ct. cushion-shaped Fancy Vivid pink diamond, which is expected to realize $23 to $28 million. As a run-up to that sale, the auction house compiled a gallery of extraordinary fancy colored diamonds it has sold in recent years.

HONG KONG

	The prevailing takeaway from the Sept. 16-23 Hong Kong Gem and Jewellery Show is that business exceeded low expectations.

	In diamonds, there was a lot of inter-dealer buying at the onset of the show – mainly stronger firms buying goods at deep discounts from dealers who were in difficulty and needed cash.

	Actual buying from retailers and jewelry manufacturers was above expectations and generally concentrated into very specific quality categories (i,e. SI and good I1 clarities) for very specific inventory needs. All told, business was down 40% to 70% from last year for most dealers.

	More buyers than usual came from the U.S., Middle East and Europe, presumably to take advantage of perceived bargains. Apart from the inter-dealer activity already mentioned, there was not a great deal of give on prices, meaning that many deals were not completed until the very end of the show. As a result, manufacturers were able to get acceptable prices for the goods they sold and buyers could get some needed inventory.

	High-end dealers were showing fewer large colorless stones, but more fancy intense and vivid yellows.

	Colored stones were in demand, but many buyers felt prices for better quality ruby, sapphire and emerald were unrealistic, given the reduced demand from China and other key gem markets. This pushed demand for substitute colored gems, such as rubellite and spinel for ruby, Tanzanite for sapphire and peridot and green tourmaline for emerald. Source: GIA @topic:8


Title: Kämmererite Cabochons from India Abstract: Figure 1. This 57 mm wide kämmererite rough and 0.57 ct faceted stone are from the Kop Daglari Mountains of Turkey. Photo by Jaroslav Hyršl.

Kämmererite is a purple variety of clinochlore, a mica-like Mg-Al-silicate with the formula (Mg,Fe)5Al[(OH)8|AlSi3O10]. Its color is caused by chromium. Kämmererite is always found in fractures of ultrabasic rocks, usually with chromite ore. The only known locality for transparent crystals is the Kop Krom chromite mine in the Kop Daglari Mountains of Turkey. Transparent crystals from this area (figure 1) can measure up to 2 cm. Some of this material has been faceted as rare collector gemstones (H. Bank and H. Rodewald, “Schleifwürdiger, roter, durchsichtiger Chlorit: Kämmererit,” Zeitschrift der Deutschen Gemmologischen Gesellschaft, Vol. 28, No. 1, 1979, 39–40, in German).

An unknown location in India recently yielded massive kämmererite that was used to carve interesting cabochons (figure 2); 10 such samples were examined in this study. The cabochons have an attractive light to dark purple color; some thinner pieces are translucent. Some of the material shows a folded texture, and this type is visually similar to charoite, a well-known ornamental stone from Siberia. The measured refractive index (RI) of the new kämmererite is approximately 1.57, very close to charoite, but clinochlore has a much lower Mohs hardness (about 2.5, rather than charoite’s 5–6). This new kämmererite is inert under UV light, but white layers in the samples show creamy fluorescence under both long-wave and short-wave UV. Raman spectroscopy revealed a characteristic group of peaks at 3877, 4063, 4175, 4500, and 4920 cm–1 in the spectrum (figure 3), confirming the material’s identity. Visible spectra further supported this conclusion. The amount of new massive kämmererite rough is unknown, and the material may remain rare.

Figure 2. These kämmererite cabochons, with widths of 27 mm and 21 mm, are from an undisclosed location in India. Photo by Jaroslav Hyršl.

Figure 3. Raman spectra showing characteristic peaks of kämmererite at 3877, 4063,
4175, 4500, and 4920 cm–1. Source: GIA @topic:2


Title: Optical Effects of Phenomenal Cabochons Abstract: Spectrolite, the trade name for labradorite from Finland, exhibits the phenomenon labradorescence − a broad flash of color across the surface caused by the internal structure of the stone. Similar to flashes of color in the Northern Lights, the blue and green hues in this spectrolite are fantastic. Left: labradorite from Madagascar.  Center and right: spectrolite from Finland. Courtesy of Black Star Trading Company, Flagstaff, Arizona. Photo by Robert Weldon/GIA

The definition of a phenomenon as “an object or aspect known through the senses,” according to Webster’s dictionary, might explain why some gemstones are called phenomenal. Or it could be because these gems are “exceptional, unusual or abnormal.”

In reality, however, it is how the structure, inclusions and properties of these gemstones interact with light to return an unusual visual effect, or phenomenon, in the parlance of gemology, that make them phenomenal.

Regardless, we experience these gemstones as fascinating and recognize that they are, in fact, extraordinary.

There are several varieties of opal: black, white, crystal, jelly, boulder and boulder matrix, to name a few. Opals can be found in Queensland, New South Wales and South Australia. This black opal cabochon has excellent play-of-color, brightness and pattern. Courtesy of Lightning Ridge Opal, Glendora, California. Photo by Robert Weldon/GIA
Phenomena Caused by Structure
Opal, labradorite and moonstone form in microscopic layers of material that are successively stacked upon each other, giving rise to phenomena based on these unique structures. When light interacts with the different structures of gem material it causes flashes of color.
Let’s see how their different structures interact with light properties.

Opal is made up of millions of tiny silica spheres stacked in layers and held together by a mixture of slightly different silica and water. When light interacts with the silica spheres, a diffraction of light causes flashes of spectral colors. These colors depend on the size of the silica spheres. Smaller spheres produce blue to green spectral colors and larger spheres produce red. This phenomenon is called play-of-color.

Labradorite is formed by alternating layers of two feldspars that have different chemical compositions. When light interacts with labradorite, the diffraction of light causes the phenomenon known as labradorescence. The perceived colors are dependent on the thickness of the alternating layers and their refractive indices.

Moonstone is composed of two different types of feldspars that vary in thickness and regularity. In moonstone, the light is scattered in many directions giving it the characteristic cloudy bluish-white light, known as adularescence.

Iridescence happens when light passes through a thin, transparent film that has a different refractive index from the surrounding material. The color patterns in soap bubbles or on a thin film of oil on water are examples of iridescence. Pearl nacre and mother-of-pearl can have just the right structure to display iridescent optical effects. Orient is a special term used to describe pearl iridescence.

This chrysoberyl ring features a very fine cat’s-eye, which visually divides the cabochon in half and reflects a light and dark color called “milk and honey.” These attributes make the cat’s-eye chrysoberyl a collector gemstone. Courtesy Richard Krementz Gemstones. Photo by Robert Weldon/GIA
Phenomena Caused by Inclusions
A star or cat’s eye is the type of phenomena caused by inclusions of tiny bands of parallel needles or hollow tubes. When the bands of needles or hollow tubes are parallel, it’s called chatoyancy or cat’s eye. When they cross, a star is formed, called asterism. For best results in star and cat’s eye material, the base of the cabochon should be cut parallel to the inclusions to produce an even effect across the dome of the cabochon. Many gemstones possess the phenomena of chatoyancy and asterism: chrysoberyl, ruby, sapphire, spinel, garnet, tourmaline, diopside and quartz are examples.
Aventurescence is a type of phenomena caused by light reflecting from small, eye-visible, plate-like inclusions of copper or sometimes hematite inclusions in sunstone feldspar. (In sunstone feldspar the aventurescence is also known in the trade as schiller). In aventurine quartz, spangles of green mica produce the glittery effect and may also give the gem its perceived body color.

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Phenomena Caused by Light Properties
Color change is another type of phenomena that occurs most dramatically in alexandrite. Chromium causes alexandrite’s color, which accounts for a close balance between red and green, varying with the type of viewing light. The finest Russian alexandrites appear green in daylight and under fluorescent light. Under incandescent light, alexandrites appear red. This phenomenon coined the romantic phrase “emerald by day, ruby by night.” Although alexandrite, named after the Russian tsar Alexander II, is the most valued color change gem, certain sapphire, spinel and garnet varieties can also show color change.
Why Are Some Gems Fashioned as Cabochons?
The term cabochon comes from the French word “caboche,” meaning “head” and refers to a gemstone that has been shaped and polished as opposed to faceted. It is also common to carve softer stones as cabochons since minute scratches show much less on a cabochon than on a faceted stone.
Light properties and opacity — the ability of light to pass through the gem, are the main factors that come into play when deciding how to cut a gemstone. If a gemstone is opaque it is usually fashioned as a cabochon. Stones with asterism and chatoyancy are cut as domed cabochons to best portray the fine, needle-like inclusions that produce these two phenomena, which would otherwise not be visible in a faceted cut.

The final decision ultimately falls on the lapidary artist or the client’s preference, but they are often fashioned into cabochons to show them off to their best — phenomenal — advantage. Source: GIA @topic:11


Title: GSA Meeting – GIA Session Abstract: Figure 1. Speaking at the GSA annual meeting, Shiyun Jin of GIA presents his research on the rapid diffusion of copper in Oregon sunstones. Photo by Robert Weldon.
A session of presentations on gemological research topics, organized by GIA, took place during the recent annual meeting of the Geological Society of America (GSA) in Portland, Oregon (October 10–13, 2021). Aaron Celestian of the Natural History Museum of Los Angeles began the oral presentations with a description of a famous piece of furniture—the Borghese-Windsor Cabinet—created in Italy around 1620. The large, multi-drawer wooden cabinet was decorated with semi-precious gems, including agate and lapis lazuli. A study of the geographic origin of the agates indicated that most were from the Idar-Oberstein area of Germany, with the remainder from another source. The early construction date of the cabinet makes Brazil an unlikely source for the agate; another possibility would have been India.
Cisil Badur of the Department of Geosciences of Auburn University in Alabama reported on plagioclase sunstones from the Columbia River basalts in Oregon that exhibit a schiller effect due to oriented copper inclusions. Argon-argon geochronological data indicate that the sunstones are younger in age than the host basalt. The author suggests this age discrepancy might be due to argon loss over geological time from the feldspar crystals, or it could be explained by the host basalt having been formed during a younger period of regional volcanism. A second talk on copper in Oregon sunstones was given by Shiyun Jin of GIA (figure 1). Rapid diffusion of copper in labradorite feldspars can induce red or green colors and aventurescence depending on the size of the exsolved copper particles. These tiny particles produce a red color by selective absorption of incident light or, in larger specimens, a green color by scattering red and orange light.
Rhiana Henry of the Department of Earth, Ocean and Atmospheric Sciences of the University of British Columbia investigated the sodium and water contents of the main varieties of beryl to develop a method to calculate water contents in beryl based on the more easily measured sodium contents. Rachelle Turnier of the Geoscience Department of the University of Wisconsin in Madison investigated oxygen isotope contents of sapphire from a variety of primary and secondary sources in Montana. She found a wide range of δ18O values in the corundum samples. This large range suggests that the Montana sapphire deposits originated from corundum formation in a variety of protolith source rocks. Aaron Palke of GIA studied what was initially thought might represent a rare new group of sapphire from the Rock Creek deposit in Montana. Although displaying a crystal shape and inclusions typical of sapphires from this area, these new sapphires exhibited low iron and gallium compositions. Dr. Palke emphasized the need for caution in using trace-element contents to decipher the geological origins of gem corundum and reported that these pale or yellow-colored sapphires do not represent a new group of material. Rather, they are typical Rock Creek sapphires that exhibit very low iron and gallium contents.
Zinc-enriched, fracture-filled, and fibrous overgrowths on classic Paraíba tourmaline crystals from Brazil were described by Darrell Henry from the Department of Geology and Geophysics at Louisiana State University in Baton Rouge. Such features are not observed in cuprian tourmalines from Nigeria or Mozambique, and thus they may be diagnostic of the original Paraíba material. Yicen Liu of the Gems and Technological Material Laboratory of Tongji University in Shanghai detailed the color mechanism and effects of heat treatment on spectral features and color for pink spinel from the famous Kuh-i-Lal deposit in Tajikistan. Che Shen of the Munsell Color Science Laboratory at the Rochester Institute of Technology described a method to calculate the color appearance of optically uniaxial colored gemstones.
Gabriela Farfan of the Department of Mineral Sciences of the Smithsonian Institution in Washington, DC discussed the effect of environmental factors on freshwater pearl mineralogy and chemistry. In a study of a lake in Kentucky, the pearl samples recorded oxygen isotope ratios and crystallographic signatures that could be correlated with seasonal variations in lake temperature, dissolved oxygen, and light levels at a one-meter depth. Chunhui Zhou of GIA reported the discovery of disordered dolomite crystals in the central internal structure of a natural pearl from a Cassius species mollusk.
Matthew Hardman of GIA discussed the use of multidimensional statistical analysis of the peak intensities of certain visible and near-infrared spectral features of irradiated green diamonds with and without green radiation stains. This type of spectral analysis offers a new approach to understanding the lattice defects in diamonds that result from natural and artificial radiation exposure. Roy Bassoo of GIA reported on a study of deuterium-hydrogen ratios in the low water content of nominally anhydrous minerals (such as olivine, enstatite, and garnet) found as inclusions in diamonds from the Guiana Shield in South America. This isotopic information could provide evidence for the geological conditions of diamond formation and growth in the upper mantle. Ira Litvak-Kochavi of the Department of Chemical Sciences at Ariel University in Israel discussed the results of a study of the influence on paramagnetic defect centers in diamond at the high temperatures (900°C or higher) that occur during facet polishing.

Figure 2. A poster illustrating the spectroscopic characteristics of blue spinel before and after heat treatment. Photo by Cathy Jonathan.

Figure 3. Dona Dirlam (left) and Barbara Dutrow (right) pose in front of a map highlighting colored stone and pearl sources utilized in seventeenth-century Indian jewelry. Photo by Robert Weldon.
In addition to the talks, GIA staff members prepared several poster presentations for the session. Jennifer Stone-Sundberg reviewed a quantitative description of the causes of color in corundum in terms of six major chromophore elements. Stephanie Persaud described five diamonds that exhibited a temporary color change from gray to yellow or blue when subjected to extremely low, liquid-nitrogen temperatures. Wasura Soonthorntantikul discussed the spectroscopic characteristics of both unheated and heat-treated blue spinels (figure 2). Heating tended to produce a less desirable grayish blue color. Paul Johnson reported on several light blue to purple type Ia diamonds that owe their color to a lattice defect associated with artificial irradiation. Dona Mary Dirlam presented a map that showed localities in Central Asia, Southeast Asia, Africa, and Sri Lanka (as well as Europe and the Americas) that were the sources of colored stones and pearls used for jewelry purposes in India during the seventeenth century (figure 3). Troy Ardon reviewed the different spectral features found in type I and type II pink diamonds. Evan Smith discussed the discovery of metallic inclusions with a heavy iron isotopic composition in high-quality type IIa colorless diamonds. This composition is attributed to the subduction of iron minerals formed by serpentinization of oceanic peridotite. Yusuke Katsurada described a study of iron and copper absorptions in the spectrum of blue/green Paraíba tourmalines and a method to determine whether a particular elbaite would correctly be classified as a cuprian tourmaline.

Figure 4. Robert Weldon talks with visitors at the GIA booth. Photo by Cathy Jonathan.

Figure 5. Nathan Renfro (left) and James Shigley (center) chat with conference attendees. Photo by Cathy Jonathan.
Overall, the 2021 GSA annual meeting saw strong attendance and notable interest in the gemology sessions and exhibits (figures 4 and 5). The 2022 event is scheduled for October 9–12 in Denver. Source: GIA @topic:1


Title: Tucson 2015: Gemologists Share the Latest Research Activities Abstract: GIA field gemologist Stanislas Detroyat, lower right, visits a sapphire mining pit worked by a group of artisanal miners near Bepeha village in the Ilakaka sapphire mining area in Madagascar. Photo by Vincent Pardieu/GIA

                      GIA’s research program has grown significantly in the past decade – in both the number of full-time researchers and the scope of activities. The team is comprised of nearly 50 staff members and consultants whose extensive academic and gem-testing backgrounds support the Institute’s wide-ranging research goals. Dr. James Shigley, distinguished research fellow at GIA in Carlsbad, presented an overview of GIA research activities at the 2015 AGTA GemFair in Tucson, Arizona.

He began with a summary of GIA’s major research efforts: to collect and characterize new gem materials to support GIA’s gem identification capabilities; to conduct experiments to determine new methods for identifying treated diamond; to develop standards for calibrating instruments across GIA’s gem identification and grading laboratories; and to examine the appearance of the major categories of fancy-shape diamonds.

One of the most important activities is to build GIA’s gem database by cataloging information from gems submitted to GIA for testing and those collected by GIA field gemology teams at the source in locations around the world. GIA has routinely conducted field expeditions – nearly 60 trips to 16 countries in the last five years – to collect material. Last year, researchers traveled to Brazil, Cambodia, Madagascar, Malawi, Mozambique, Myanmar, Sri Lanka, Thailand, Vietnam and Zambia.

“Travelling to these countries and collecting gem specimens directly at the source – seeing them come from the earth – ensures they have not been treated and are not synthetic,” Shigley said. Knowing without question where a gem was sourced and understanding its distinctive characteristics also helps researchers make country-of-origin determinations, he said.

Researchers archive the rough specimens they collect, characterize them using specialized instrumentation, then record the results in a database shared with all GIA laboratories.

Shigley said one of the biggest challenges is how to identify gem treatments. In a recent study, researchers collected data on unheated (brown) zoisite, and then heated the gems to known temperatures to examine differences in color and spectra after the treatment. The heated gems turned a dark blue and purple color – a variety of zoisite known as tanzanite. Researchers examined the visible spectra and inclusions then compared this information to the data from the same stone before it was heated.

These experiments determined that visible spectra are inconclusive in determining whether a tanzanite has been heat treated or not; the absence of three pleochroic colors may suggest that a tanzanite is unheated, but it can be difficult to observe all three colors in a cut stone; and unaltered fluid inclusions are perhaps the best indication that a stone has not been heat treated, while ruptured fluid inclusions are an indication of heat treatment.

Shigley explained the importance of accurate and efficient instruments in gemological research and the GIA laboratory. Instrumentation at all GIA lab locations are regularly monitored and calibrated to ensure consistent measurements. He mentioned the GIA DiamondCheck, a device introduced in early 2014 that differentiates natural diamonds from those that are potentially synthetic or color-treated, as an example. GIA, working with the World Federation of Diamond Bourses (WFDB), has made the DiamondCheck available on a lease basis at no cost to 20 diamond bourses and industry organizations around the world.

Shigley also reviewed the progress on a cut evaluation system for fancy-shape diamonds. GIA introduced the cut grading system for standard round brilliant diamonds (in the D-to-Z color scale and the Flawless-to-I3 clarity range) in 2006. Since then, the research team has investigated the cut and appearance for the most common fancy-shape diamonds. Researchers interviewed more than 440 experts from different backgrounds in Antwerp, Hong Kong, Mumbai, New York, Tel Aviv and Tucson in 2014. Participants were asked to examine fancy-shape diamonds and record what they saw to help determine industry preferences for certain aspects of diamond appearance.

A GIA laboratory team continues to evaluate client-submitted stones on a daily basis, noting results in a database that contains more than 9,000 observed fancy-shape diamonds. While no decision has been made to offer a cut grade for these diamonds, some basic concepts for an evaluation system are beginning to be uncovered.

Shigley asked Dr. Christopher M. Breeding, a research scientist at GIA in Carlsbad, to share research updates on diamond fluorescence, and synthetic and irradiated diamonds.

Approximately 35% of diamonds on the D-to-Z color grade scale exhibit fluorescence under long-wave ultraviolet (UV) light, Breeding said. Blue is the most common color, followed by yellow. Of the diamonds that fluoresce, 38% are faint and 62% display medium or strong fluorescence. For the majority of diamonds, the strength of fluorescence does not have an effect on appearance except in rare instances of very strong blue fluorescence. Fluorescence is recorded on a GIA Diamond Grading Report as an identification feature.

There are several UV sources that can be used to detect long-wave fluorescence, including hobbyist UV lamps, mercury UV lamps and LED UV loupes. Variations in wavelength in lamp output can affect the observed fluorescence by shifting the fluorescence color. Breeding said GIA is developing a new long-wave LED UV source with no side-bands, a longer operating life, no glass filter and more consistent illumination conditions between units. This new, compact and light-weight source will help standardize the way fluorescence is observed to ensure accuracy and improve consistency.

Breeding also discussed synthetic diamonds, which have become more prevalent and available in recent years. Companies that create colorless HPHT (high pressure, high temperature) and CVD (chemical vapor deposition) synthetic diamonds have produced relatively large diamonds with good color and clarity, he said. The full results of one of the studies – HPHT diamonds from the AOTC Group – were published in the Spring 2014 issue of Gems & Gemology (G&G).

Next, Breeding shared new research on irradiation color treatments, which he said can be challenging to identify because natural radiation in diamond produces a similar green coloration as when one is treated. In recent years, naturally irradiated, light-colored diamonds have been treated to create slightly more intense colors. Research on diamond color treatments remains an ongoing process, but GIA is constantly exploring new ways to ensure that these treatments can be identified.

Shigley closed by stressing that all of GIA’s research efforts – from field expeditions to experiments – serve to protect those who buy or sell gems. The information gained from research ensures GIA’s grading and identification reports are accurate and complete, and is also shared through education, G&G and GIA’s website.

	Dr. James Shigley, left, and Dr. Christopher M. Breeding. Photos by Kevin Schumacher/GIA Source: GIA @topic:7


Title: GIA Alumni Collective Abstract: Deeta Thakural, Mélanie Matthes, Yolette and Briana Hodge, and Aldis Hodge are some of GIA’s featured graduates on the Alumni Collective website.
The GIA Alumni Collective offers an exciting new networking platform for GIA graduates. The online community at collective.gia.edu allows a diverse group of users to access both live and self-paced continuing education seminars, join virtual chapters, connect with global alumni, and more. The site also puts GIA alums in the spotlight (see above), celebrating those who uphold the highest standards of GIA’s consumer protection mission.
Deeta Thakural earned her Graduate Gemologist diploma at GIA’s Mumbai campus. As a fourth-generation jeweler, Thakural was drawn to design. Her award-winning collections blend organic shapes and rich hues that reflect the natural world.
Mélanie Matthes studied at GIA’s Carlsbad campus, receiving Graduate Gemologist, Pearls Graduate, and Applied Jewelry Professional diplomas. Her education, fascination with gemology, and love of history led to her career with a well-known auction house, handling some of the world’s most extraordinary jewelry pieces.
Learning from GIA guided each member of the Hodge family down a different path. Aldis, a self-taught watchmaker and business owner, and his sister Briana, a visual specialist and photographer, encouraged their mother, Yolette, to explore her childhood fascination with diamonds and earn a Diamonds Graduate diploma.
Visit https://collective.gia.edu/meet-the-collective.html to read stories from these alumni and more. Source: GIA @topic:9


Title: Puzzle-Like Gemstone Designs Abstract: Figure 1. Trays of Steve Walters’s unique gemstone carvings displayed at the 2022 AGTA show in Tucson. Photo by Tao Hsu; courtesy of Rare Earth Mining Co.
At the AGTA show, Rare Earth Mining Co. (Trumbull, Connecticut) offered a vast array of fine and unusual gem materials unavailable anywhere else in the trade. Among the opalized wood, Tiffany stone, honeycomb petrified wood, and many other varieties was one of the most expansive Steve Walters collections seen at Tucson (figure 1).
While Walters himself did not attend the show this year, Rare Earth Mining Co. was eager to detail his work for us. A master gemstone carver specializing in one-of-a-kind gemstone designs in Utah, Walters has been in the business for more than 50 years. He creates his carvings for jewelry designers, to help them achieve a unique look.
Walters’s designs feature a perfect mix of traditional and exotic gemstones, expertly paired and carved to create a dramatic shape and color story. All done by hand, Walters uses titanium to bridge together and inlay the different gemstones.
Among the wide variety of gemstones used in Walters’s carvings were onyx; chrysocolla; tourmalinated and rutilated quartz; amethyst, citrine, and ametrine with striking color zones; rock crystal quartz backed with onyx and gold foil; lapis lazuli; various agates; Australian and pink opals; and meteorite. Every piece is finished with a mother-of-pearl backing with his signature (figure 2), ready to be set into a showstopping piece of jewelry.

Figure 2. Left: This citrine “flame” top is connected to a chrysoprase “main body.” Next to the chrysoprase is a portion made of a black chalcedony backing, covered by 24K gold leaf and capped by rock crystal quartz. The piece is completed with a freeform ametrine. Right: All pieces have a mother-of-pearl backing with Steve Walters’s signature. Photos by Kevin Schumacher. Source: GIA @topic:10


Title: G&G Announces Most Valuable Article Awards Abstract: A matched pair of Kashmir sapphires, approximately 7 carats total. Photo by Robert Weldon/GIA. Courtesy of Amba Gem Corporation

Gems & Gemology is pleased to announce the winners of the Dr. Edward J. Gübelin Most Valuable Article Awards for 2019. G&G’s Most Valuable Article Award recognizes the three most groundbreaking articles from the previous year. For the first time in the competition’s history, the ballots were cast by the journal’s editorial review board.
First place went to “Geographic Origin Determination of Blue Sapphire,” by Aaron Palke, Sudarat Saeseaw, Nathan Renfro, Ziyin Sun and Shane McClure. This article, from the Winter 2019 special issue on geographic origin, detailed GIA’s methodology for establishing the origin of blue sapphire.

Aaron Palke is senior manager of research at GIA in Carlsbad, California. He holds a Ph.D. in geology from Stanford University.

Sudarat Saeseaw is a senior manager of colored stone identification at GIA in Bangkok. Saeseaw received her master’s degree in analytical chemistry from Mahidol University in Thailand.

Nathan Renfro is manager of colored stones identification at GIA in Carlsbad. He earned a bachelor’s degree in geology from Appalachian State University in North Carolina.

Ziyin Sun is a research associate in the gem identification department at GIA in Carlsbad. He holds a bachelor’s degree in chemistry and a master’s degree in analytic chemistry from Nanjing University in China.

Shane McClure is global director of colored stone services at GIA in Carlsbad and co-editor of G&G’s Lab Notes section. He is well known for his many articles and lectures on gem identification.

A variety of rubies from Niassa and Montepuez in northern Mozambique that were mined in 2009–2010. They include untreated and heated stones weighing between 1.07 and 4.62 ct. Photo by Robert Weldon/GIA. Courtesy of Tommy Wu, Shire Trading Ltd
Two articles tied for second place. From the Summer 2019 issue was “A Decade of Ruby from Mozambique: A Review,” by Wim Vertriest and Sudarat Saeseaw. This report reviewed the mining history, market impact and properties of ruby from northern Mozambique near Montepuez, now the world’s most productive source.
Wim Vertriest is supervisor of field gemology at GIA in Bangkok. Vertriest has visited gemstone mining areas worldwide and oversees the field gemology department and curates GIA’s colored stone research collection in Bangkok. He obtained a master’s degree in geology (geodynamics and geofluids) from KU Leuven in Belgium.

Sudarat Saeseaw was profiled in the first-place entry.

Tranquil reflecting pools add to the symmetry of the Taj Mahal. Photo by Robert Weldon/GIA
Sharing second-place honors was “Gemstones in the Era of the Taj Mahal and the Mughals,” by Dona Mary Dirlam, Chris Rogers and Robert Weldon. This Fall 2019 piece explored the gem ornamentation of an iconic landmark, with a look at the jewels of the Mughal dynasty.

Dona Dirlam is librarian emerita at GIA’s Richard T. Liddicoat Gemological Library and Information Center in Carlsbad, California, where she established and expanded the collection known as the world’s leading resource center for gems, gemology and jewelry. Dirlam holds a master’s in geology and geophysics from the University of Wisconsin, Madison.

Chris Rogers is a research librarian at GIA’s Richard T. Liddicoat Gemological Library and Information Center. She holds a bachelor’s degree in English from San Diego State University and a master’s in library and information science from San Jose State University.

Robert Weldon is director of GIA’s Richard T. Liddicoat Gemological Library and Information Center. He is well known for his gem photography and has contributed to scores of international publications and several gem-related books.
Congratulations to all of this year’s winning authors! Source: GIA @topic:1


Title: Iridescent Abalone Shell Abstract: The surface of this colorfully iridescent abalone shell resembles a topographic map. Photomicrograph by Michaela Stephan; field of view 23.14 mm.

The glowing rainbow-colored image resembling a topographic map in the figure above was captured over the polished surface of an abalone shell. Abalone is a common marine gastropod (univalve mollusk) belonging to the family Haliotidae and the genus Haliotis. Abalone mollusks are distributed along coastal waters worldwide and associated with rocky habitats. They are well known as nutrition-rich seafood, and their ear-shaped shells are also popular in jewelry owing to their uniquely vibrant iridescent nacre known as mother-of-pearl.
Iridescence is an optical phenomenon frequently observed in gem materials, as well as in nacreous shells and pearls. Orient is the specific term for the iridescent effects attributed to interference and diffraction of light in the multilayered aragonite platelet structure. Shells and pearls produced by the Haliotis species generate the highest degree of iridescence, with a full range of distinct rainbow colors. These colors are caused by the fine grating structure created by the thin and closely packed nacre layers, similar to that of a diffraction grating (T.L. Tan et al., “Iridescent colours of the abalone shell (Haliotis glabra),” Journal of Gemmology, Vol. 29, No. 7/8, 2005, pp. 395–399). This extraordinary property lends a charming appearance to shell, pearl, and assembled cultured blister “pearls” (mabe) produced by abalone mollusks and makes them widely popular in the gem and jewelry industry. Source: GIA @topic:5


Title: Changes Coming for De Beers’ Sights Abstract: These diamonds – 22.32 ct macle, left, and 1.01 ct round brilliant – are from the Oppenheimer Collection. Gift of DeBeers, photo by Robert Weldon/GIA

	This week’s De Beers’ sight is unlikely to feature significant price increases, but company executives are laying out a series of major changes in the sight system that will begin in January.

	First, De Beers will tighten the credit reporting requirements for each client. The company has reportedly backed away from a more strict policy proposed by major industry banks that would sharply reduce a client’s acceptable debt-to-equity ratio. Many major clients, however, continue to struggle with high debts and slow collections and would be unable to meet those more stringent requirements.

	Earlier this year, the banks financing the diamond industry sharply reduced their credit exposure. They began to require that sightholders and other rough dealers fund a minimum of 30% of their purchases themselves, instead of the banks providing 100% funding.  In addition, they trimmed their lending ratio to as little as 60% of receivables.

	Second, the company reportedly introduced new client selection criteria for existing sightholders based, in part, on previous buying. During the past several years, clients have been refusing some rough diamond assortments they believe are too expensive for the market. Some also deferred purchases in hopes that De Beers would lower prices on those goods in future sights.

	De Beers also is reportedly introducing a new class of client, an Accredited Buyer, who will be able to purchase rough that is not contracted to existing clients. It is likely that most of the Accredited Buyers will be selected from buyers who participate in De Beers’ rough diamond auctions. The company already has appointed three sightholders from its auction buyer list.

SYNTHETICS: Concern over the infiltration of undisclosed synthetics into the diamond pipeline has prompted the Indian government, at the urging of the leading Indian industry organization, to propose a 10% import duty on synthetic polished diamonds.

	All, or nearly all, synthetic diamonds are manufactured outside of India. The Gem and Jewellery Export Promotion Council in India is pushing the extra duty to reduce the price differential between natural and synthetic diamonds, it said in a statement. The government is also considering a 5% duty on synthetic rough diamond imports.

	Although concern over the advent of synthetics is rising following several reported discoveries of undisclosed stones mixed in parcels of naturals, GIA remains confident it can differentiate all lab-grown diamonds from natural stones. In addition, GIA and other firms have developed detection equipment to screen parcels of diamonds that are generally too small to be sent to gemological labs for grading. Source: GIA @topic:8


Title: New Azurite-Malachite Mixture from Peru Abstract: Figure 1. This polished vein of azurite with malachite and chrysocolla mined from Cochapata measures 8.5 cm wide. Photo by J. Hyršl.

Green malachite, Cu2(CO3)(OH)2, is very popular as an ornamental stone, with huge quantities coming every year from deposits in the Katanga Province of the Democratic Republic of Congo. Blue azurite has a similar chemical composition, Cu3(CO2)2(OH)2, but is much more rare. Cabochons of pure azurite are usually quite dark and not very attractive. A blend of the two is much more appealing for jewelry, but this combination is seldom found. Attractive azurite-malachite mixtures are known mainly from old finds in Bisbee and Morenci, both in the U.S. state of Arizona. There was also a find of malachite-azurite-gypsum mixture from Peru’s Moquegua region in 2012 (J. Hyršl, “Malachite-azurite from Peru,” Journal of Gemmology, Vol. 34, No. 7, 2015, p. 564).

Another new azurite-malachite mixture appeared in 2016 and was originally described as from Puno, in southeastern Peru. In fact, it is from Cochapata, in the Cotabambas Province about 50 km southwest of Cuzco, situated in high mountains. According to a dealer who visited the locality, there are several outcrops of oxidized copper veins on a steep hill exploited by artisanal miners. The veins are up to about 20 cm wide, but the parts most useful for cutting are usually only a few centimeters wide. Several tons of the rough have already been sold in Lima to foreign dealers, with the largest piece weighing 80 kg.

Figure 2. These azurite-malachite cabochons, fashioned from Cochapata material, measure up to 31 mm. Photo by J. Hyršl.
Deep blue azurite is the main mineral found today in Cochapata, accompanied by light green malachite and, less commonly, light blue chrysocolla (figure 1). The most attractive specimens have malachite with a banded structure, but some possess a brecciated structure (figure 2). The rarest samples are stalactites of malachite up to 5 cm in length. Some were sliced perpendicular to the elongated growth direction to prepare very attractive stones with an agate-like structure (figure 3).

Figure 3. A cross-section of a 25-mm-wide malachite double stalactite from Cochapata. The stalactite on the right shows malachite with an azurite center. Photo by J. Hyršl. Source: GIA @topic:2