# Publication Year: 2015
# Title: Pezzottaite Debuts as the Newest Trapiche Gem Mineral
# Abstract: Figure 1. As viewed through the pinacoid face, strong oblique fiber-optic lighting illuminates the six-legged trapiche structure emanating from the c-axis of this doubly terminated 2.33 ct pezzottaite crystal. Photo by Kevin Schumacher.

Since the first enigmatic six-spoked emeralds were sent to GIA in the mid-1960s for analysis (H.L. McKague, “Trapiche emeralds from Colombia,” Fall 1964 G&G, pp. 210–213, 223), the family of trapiche-type gem minerals has grown to include a variety of species and morphologies. One of the latest mineral varieties to exhibit the rare trapiche form is a relatively new and rare mineral itself: pezzottaite.

Following its appearance at the 2003 gem shows in Tucson, pezzottaite has quickly become an item coveted by gem and mineral collectors around the world. A member of the beryl group and with trigonal symmetry (the beryl species has hexagonal symmetry), it was approved by the International Mineralogical Association in September 2003 as a unique species and named after mineralogist Dr. Frederico Pezzotta (see B.M. Laurs et al., “Pezzottaite from Ambatovita, Madagascar: A new gem mineral,” Winter 2003 G&G, pp. 284–301).

In 2004, while working in the gem markets of Mae Sai and Mae Sot along the border of Thailand and Myanmar, Elaine Rohrbach of Gem-Fare obtained a small collection of pale pink trapiche crystals and crystal fragments reported to be of Burmese origin. Laboratory analysis later proved these crystals to be the cesium-containing mineral pezzottaite (previously confirmed localities include Madagascar and Afghanistan).

Figure 2. Another well-developed, doubly terminated pezzottaite crystal from the same
locality, weighing 6.17 ct and measuring 11.19 × 10.71 × 8.61 mm, has separate crystals
growing at random angles on each pinacoid face. Each of these smaller crystals also
exhibits trapiche growth. The white trapiche growth reaches all six prism faces in both of
the tabular crystals, as well as those faces on the secondary growth crystals. Photo by
Elise A. Skalwold.
A doubly terminated, well-developed crystal obtained by one of the authors (JIK) exhibits the tabular prismatic habit characteristic of the species, but with a complete six-spoke trapiche structure that is clearly visible in both reflected and transmitted light (figure 1). Another doubly terminated crystal obtained by author EAS from the same parcel shows secondary crystals growing out of each pinacoid face, each of which are also trapiche crystals (figure 2). Similar to trapiche crystals of other mineral species, each of the spokes radiates from the central c-axis toward the prism faces and in a plane parallel to the basal pinacoid. Exploring the former crystal’s inner world revealed not only the details of the white spokes and a spray of golden brown needles and eye-visible black needles, but also a delightful surprise: minute euhedral blue crystals (figures 3 and 4). Unfortunately, the black needles were not identifiable despite their distinct Raman spectrum. Due to their depth within the host, the brown needles and blue crystals remain mysteries as well. Let this be a lesson that nondestructive testing cannot always provide answers, but we can be content with exploring the beauty of the micro-world while leaving some mysteries for the future.

Figure 3. Eye-visible dark needles were seen throughout the pezzottaite crystal with diffused transmitted illumination. Despite a clear Raman signal, the features could not be conclusively identified. Photomicrograph by Nathan Renfro; field of view 1.10 mm.

Figure 4. Using diffused transmitted and oblique fiber-optic illumination, a golden-brown spray of needles is shown deep in the crystal, along with a bright blue crystal to its right. Their depth precluded analysis by Raman spectroscopy. Photomicrograph by Nathan Renfro; field of view 0.91 mm. @chapter:7 @chapter:0 @chapter:7


# Publication Year: -
# Title: Diamond Care and Cleaning Guide
# Abstract: Consumers know diamond from the slogan “A Diamond is Forever”. With some care considerations this is relatively true. The Asscher cut was popular decades ago and is again a very popular cut style. This stone has exceptional quality being D color and VVS2 Clarity.

                      “A Diamond is Forever” is one of the world’s best-known advertising slogans. It has many different meanings. It refers to diamond’s timeless appeal. It refers to diamond’s icy beauty. And it also refers to diamond’s durability. One result of the diamond formation process is its incredible durability.

Durability is a gemstone’s ability to withstand wear, heat, and chemicals. Durability consists of three properties: hardness, toughness, and stability. Hardness means how well a gemstone resists scratches and abrasion. Toughness describes how well a gemstone resists breaking and chipping. Stability means how well a diamond resists chemicals and temperature changes.

Hardness
Gem and mineral hardness is measured on the Mohs scale. The scale originated in 1812 when German mineralogist Friedrich Mohs chose ten minerals and assigned numbers to them, based on the relative ease or difficulty with which one could be scratched by another. But the Mohs scale is deceptive. The steps between the minerals are not evenly spaced. For example, diamond is only one number away, but it’s many times harder than gems in the corundum family. Only a diamond can scratch a diamond.

Something the Mohs scale doesn’t show, but that’s equally important to the diamond industry, is that diamond can also scratch any of the precious metals used for settings. That means a diamond that’s loose in its setting can wear through a prong over time.

	Diamond rates highest on the Mohs hardness scale, at number 10.
Toughness
Any stone, including a diamond, will break if it’s hit hard enough in the right place. Toughness is a measure of how well a gem can survive an impact and resist breaking, chipping, or cracking.
Diamonds are tougher in the directions where the atoms are bonded tightly together, less tough where they’re not so tightly bonded.

	Cutting styles with pointed corners or ends are often set with prongs to protect the corners from chipping. - Courtesy Ambar Diamonds
The weakest directions are the ones where the atoms are farthest apart. It’s easier to break a diamond in those directions, which are called cleavage directions. A cutter can cleave a diamond by hitting it sharply in the cleavage direction. But even after cutting, a hard blow can still cleave a diamond. This can happen during the setting process, or even when it’s being worn.

Stability
Stability is a term that describes how well a diamond resists temperature changes and chemicals. Diamonds are very stable. They’re invulnerable to virtually all acids, for one thing. The cutting process generates a lot of heat, but diamonds usually endure intact. Situations that are more threatening to a diamond’s stability are those that involve sudden and extreme temperature changes. Those changes can cause thermal shock and create new fractures and cleavages or cause existing ones to spread.

Diamonds will burn at about 1562°F (850°C). House fires and jewelers’ torches can reach that temperature.

	A house fire caused the white, cloudy appearance of this diamond (left). The stone was recut to remove the burned area, reducing the diamond’s size, but leaving no sign that it was ever damaged (right).
Cleaning
Diamonds can be cleaned safely with lint-free cloths, commercial jewelry cleaning solutions, and household detergents.

Harsher cleaning methods are not recommended for home use. These include powdered abrasive household cleansers, ultrasonic cleaners, and steam cleaners.

	Ultrasonic cleaners and steam cleaners can loosen gemstones in their settings. Jewelry professionals carefully examine jewelry for loose stones before using these devices. @chapter:41 @chapter:1 @chapter:41


# Publication Year: 2021
# Title: Melo Pearl Found in a Melo Shell
# Abstract: Figure 1. A Melo pearl measuring 20.50 × 19.25 × 18.85 mm and weighing 55.10 ct. A fine crack is visible across the center of the surface. Photo by Nutapol Kitdee.

Over the years, there have been a number of reports relating discoveries of natural pearls in edible oysters (e.g., Fall 2019 Gem News International, pp. 439–440; Fall 2020 Lab Notes, pp. 420–422). However, similar discoveries are much rarer in gastropods, such as species of the Melo genus. Such finds often make headlines, as was the case recently in Thailand when a few discoveries were reported on social media. One of these remarkable stories, titled “A delicious find,” was posted on www.facebook.com/GIAEducation on April 9, 2021. It detailed the discovery of a large oval orange Melo pearl measuring 20.50 × 19.25 × 18.85 mm and weighing 55.10 ct that was submitted to GIA’s Bangkok laboratory for testing in September 2020 (figure 1). The owner claimed to have accidentally found this pearl in an inexpensive Melo shell he purchased with another shell from a local market in Rayong Province, eastern Thailand.

Figure 2. Various flame structure patterns visible on the pearl’s surface: short patchy flames with a fine surface-reaching crack (left), thin elongated flames with some minor natural features (center), and flames reminiscent of Christmas trees (right). Photomicrographs by Kwanreun Lawanwong; fields of view 19.20, 7.20, and 3.60 mm, respectively.
This note offers additional detail on the pearl that was the subject of that story. To the eye, the pearl looked exactly as a Melo pearl should. Its size and color were consistent with that type of pearl, and it exhibited various flame structure patterns on its surface: short patchy flames, thin elongated flames, and “triangular” flames reminiscent of Christmas trees (figure 2). These features were consistent with flame structures previously observed on Melo pearls (D.J. Content, Ed., Pearl and the Dragon: A Study of Vietnamese Pearls and a History of the Oriental Pearl Trade, Houlton, Maine, 1999, pp. 90–92; H. Htun et al., “Melo ‘pearls’ from Myanmar,” Fall 2006 G&G, pp. 135–136; V. Pardieu, “Concise Field Report: Melos and their pearls in Vietnam,” GIA Research News, https://www.gia.edu/ongoing-research/melo-pearls-from-vietnam, 2009). Some other associated minor surface features were visible, together with a long fine crack traversing one area (figure 2, left).

Figure 3. Microradiographs in two directions showed no obvious internal growth structure. Only a fine dark line showed in one orientation, which corresponded to a surface-reaching crack (left, indicated by the white arrows).
Microradiography revealed no obvious internal growth structure (figure 3). Only the fine crack previously mentioned showed as a dark fine line in the correct orientation (figure 3, left, indicated by the white arrows). The absence of any surface modification and the presence of natural surface features, in addition to the lack of banded structure typically observed in shell samples, proved this was a pearl and not an imitation fashioned from Melo shell (Summer 2006 Lab Notes, pp 166–167; N. Sturman et al., “An imitation Melo pearl,” GIA Research News, https://www.gia.edu/gia-news-research/imitation-melo-pearl, 2011).
Spectral analyses using Raman, photoluminescence (PL), and UV-Visible (UV-Vis) spectroscopy proved the pearl’s color was of natural origin. Raman spectra revealed features at 701, 705, and 1085 cm–1 identifying aragonite, together with polyenic peaks at 1130 and 1520 cm–1 responsible for the orange coloration. These polyenic peaks are consistent with other naturally colored porcelaneous pearls (S. Karampelas et al., “Polyacetylenic pigments found in pearls and corals,” 30th International Gemmological Conference Proceedings, 2007, pp. 49–51; Summer 2018 Lab Notes, pp. 211–212).
An interesting declaration made by the pearl’s owner probably explains the presence of the fine eye-visible surface crack. The Melo shell containing the hidden pearl was boiled, and the Melo pearl was only discovered when the meat was being prepared for consumption. Hence, it is likely that the temperatures and duration applied during the cooking process caused the crack’s formation. This point has been mentioned by a number of pearl traders during discussions with lab gemologists over the years, so it seems an important consideration when such cracks are observed. Even so, the notable size, unmodified surface, perfectly formed oval shape, and intense natural color all combined to make this a desirable and special pearl. @chapter:11 @chapter:4 @chapter:11


# Publication Year: 2016
# Title: Iridescent Inclusion in Tanzanite
# Abstract: Figure 1. The iridescence in this tanzanite hints at the complex and dynamic world just below the surface, in the form of crystallographically aligned iridescent cleavage. Photomicrograph by Danny Sanchez; field of view 3 mm.

	Gemmy blue zoisite, more commonly known as tanzanite, is valued for its pleasing violet to blue hue. One tanzanite specimen from Merelani, Tanzania, was purchased by the author for an entirely different aesthetic feature: its well-defined, minimally damaged crystal faces. Microscopic observation uncovered a hidden bounty of color just below the surface, particularly when subjected to metal halide oblique lighting. Crystallographically aligned, vividly iridescent colors resulting from fine separations along the stone’s cleavage planes (figure 1) were visible using fiber-optic light.

	Photographing inclusions can be challenging, to say the least. When light enters the host material, each delicately nuanced feature is affected in unpredictable ways. Documenting surface textures or crystal faces is equally difficult; the challenges are manifold when attempting to photograph both simultaneously. Knowledge of lighting techniques is useful in such situations (N. Renfro, “Digital photomicrography for gemologists,” Summer 2015 G&G, pp. 144–150). In this instance, a combination of diffused lighting and direct pinpoint lighting was used to illuminate both features. Low-intensity diffused light was reflected from the surface of the stone so as to illuminate the crystal faces without overpowering the iridescent colors brought from below. Once lit, a short “stack” of images captured the appropriate amount of depth into the stone. @chapter:2 @chapter:0 @chapter:2


# Publication Year: 1989
# Title: Spring 1989 Gem News International
# Abstract: Tucson ‘89
            "Angelite"
            Garnet
            Man-Made "Inclusion" Specimens
            Mother-of-Pearl Gambling Chips
            Plastic Cameo Imitations
            Synthetic Quartz
            Tourmaline from Nigeria
Colored Stones
            A Beautiful New Form of Orthoclase
            New Emerald Deposit near Nova Era, Brazil
            Record-Size Spessartine Garnet
            Star Almandine Garnet from Idaho
            Wollastonite for Carving
Instrumentation
            New Developments in Spectroscopy
Synthetics and Simulants
            Recent Advances in Gem Diamond Synthesis
            Synthetic Diamonds by Detonation
            Synthetic Diamond vs. Cubic Zirconia
            Emerald Imitation from Quartz
            Heat-Treated Lepidolite?
            Imitations from Africa
            "Reconstructed" Azurite-Malachite
            Synthetic Amethyst Alert
Erratum
            Mr. Francisco Muller Bastos: 1988 G&G Challenge
In Memoriam
            Irwin Moed 1918-1988 @chapter:16 @chapter:1 @chapter:16


# Publication Year: 2006
# Title: Winter 2006 G&G Lab Notes
# Abstract: Lizards in Imitation Amber
Large Demantoid Garnet of Exceptional Color
Unusually Large Fancy White Diamond with Whitish Banding
Prolonged Change of Color in Pink Diamond
Strand of Natural Nacreous and Non-nacreous Pearls
Poudretteite
Pyroxmangite, an Unusual Gem

To view the full section, download the PDF above. @chapter:18 @chapter:0 @chapter:18


# Publication Year: -
# Title: Liddicoatite: Vibrant Gem Honors Father of Modern Gemology
# Abstract: Most liddicoatite comes from Madagascar, including this slice from the Anjanabonoina pegmatite. Coutresy Harvard Mineralogical Museum, photo by Robert Weldon/GIA

                      Liddicoatite – a calcium-rich lithium tourmaline – is revered for its complex color zoning that often displays several vibrant colors. The common trigonal pattern comes to life when the gem is fashioned as polished slices that highlight the characteristic red, purple, green and yellow hues of this striking gem. Multicolored zoning – what gemologists refer to as parti-colored – occurs when the trace elements change in concentration or composition during a crystal’s growth.

First recognized as a separate mineral in 1977, liddicoatite was named in honor of Richard T. Liddicoat (March 2, 1917 – July 23, 2002), the second president of GIA who is often referred to as the “Father of Modern Gemology.” Dr. Pete J. Dunn and his colleagues from the U.S. National Museum of Natural History identified liddicoatite as a distinct mineral and chose the name in recognition of Liddicoat’s many contributions to gemological knowledge and education, including his creation of the International Diamond Grading System and its well-known and universally recognized scales for measuring the color and clarity of diamonds.

Liddicoatite – along with elbaite, dravite, uvite and schorl – is one of the major tourmaline species. Its appearance is similar to elbaite, and it can only be distinguished through chemical analysis. Most known liddicoatite comes from the Anjanabonoina pegmatites in central Madagascar.

View Gallery @chapter:7 @chapter:0 @chapter:7


# Publication Year: 2024
# Title: New Sapphire Material from Kashmir
# Abstract: Figure 1. Left: Two Kashmir sapphire rough crystals: 77.00 ct unheated (left) and 25.20 ct heated (right). Right: Unheated Kashmir sapphires. Left to right: 1.29 ct pear shape, 2.60 ct cushion cut, 21.09 ct dragon carving, and 4.08 ct oval cut. Photos by Robert Weldon; courtesy of Eddie Cleveland of KashmirBlue and Jeffery Bergman of EighthDimensionGems.
The legendary and remote sapphire mines of Kashmir, the disputed Himalayan territory between India and Pakistan, produced the finest-quality sapphires from 1890 through the 1920s. These coveted gems made their way south to Mumbai and eventually to Europe and America. Now, 100 years later, rough stones are still found, deposited through erosive processes. During the summer months, Kashmiri shepherds migrate north through the higher Himalayas, where they occasionally find sapphires in the riverbeds and on the hillsides. The glacier-tumbled rough typically exhibits rounded surfaces, affectionately referred to as “plums in pudding” by English geologist C.S. Middle in the 1930s (figure 1, left). Many in the trade believe the best available material dates back to five productive years in the 1880s.

Figure 2. Two untreated Kashmir sapphire rings. Top: 1.59 ct cushion-cut cornflower blue sapphire set in white gold with VVS baguette diamonds. Bottom: 1.00 ct oval-cut medium lighter blue sapphire set in an Art Deco style diamond platinum ring. Photo by Robert Weldon; courtesy of Eddie Cleveland of KashmirBlue and Jeffery Bergman of EighthDimensionGems.
Exhibited at the AGTA show by Jeffery Bergman (EighthDimensionGems, Bangkok) and Mayer & Watt (Maysville, Kentucky), this selection of newly found rough crystals, loose cut gems (figure 1, right), and mounted Kashmir sapphires (figure 2) was all recently faceted by lapidary artisan Eddie Cleveland of KashmirBlue, who lived in Kashmir researching the historic mines for more than a decade. Cleveland uses his heat-treating experience to turn much of the pale grayish geuda-like rough to rich, well-saturated blues through standard high-temperature heating techniques. A limited amount of new material is found each year, and only a few pieces find their way to market. @chapter:1 @chapter:0 @chapter:1


# Publication Year: 1983
# Title: Fall 1983 G&G Lab Notes
# Abstract: A Large Cat's-Eye Alexandrite
Amber, in Plastic
Diamond Simulant
Mysterious Wear on a Diamond Ring
Painted Diamonds
Diaspore, a Rare Gem Material
Emerald
Jade Substitute
Lapis Lazuli, a New Imitation
Synthetic Opal
Cultured Button Pearls
Pinite, a Massive Form of Muscovite
Zoisite (Tanzanite)

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


# Publication Year: 1995
# Title: Fall 1995 G&G Book Reviews
# Abstract: “Standard Catalog of Gem Values, 2nd Edition”
By Anna M. Miller and John Sinlzankas, 271 pp., illus., publ. by Geoscience Press, Tucson, AZ, 1994. US$24.00

“Diamond Exploration into the 21st Century”
Edited by W.L. Griffin, 367pp., illus., publ. as Vol. 53 of the Journal of Geochemical Exploration, Elsevier Science, Amsterdam, 1995, US$250.

 “The New Alchemists: Breaking Through the Barriers of High Pressure”
By Robert Hazen, xvi, 287pp., illus., publ. by Smithsonian Press, Washington, DC, 1993. US$23.00

To view the full section, download the PDF above. @chapter:35 @chapter:1 @chapter:35


# Publication Year: -
# Title: Retailers, Diamond Trade Still Vying Over Prices
# Abstract: The octahedron rough weighs 15.98 carats; the faceted diamonds are between 3.00 and 3.50 carats. Photo by Robert Weldon/GIA

	The tug-of-war between retailers, diamond miners and manufacturers over prices continues even as the world economy slowly improves.

	A number of diamond price monitoring services reported that diamonds have given up most of the price gains made earlier in the year. Additionally, Blue Nile Chief Financial Officer David Binder, speaking in a news conference announcing first quarter results, said that consumers are resisting paying high prices for polished, making it difficult for diamond manufacturers and wholesalers to pass on their increased costs.

	The pressures on middle-class consumers have been well-reported and have affected retail demand for many products, including jewelry. However, one recent report notes a growing caution among U.S. luxury buyers as well.

	Unity Marketing’s survey of luxury buyers – who have driven the increase in diamond and jewelry buying in the U.S. over the past several years – found that those consumers plan to hold the line on spending, putting more of their discretionary funds into investments and savings.

	Online retailer Blue Nile reported its first quarter sales rose 6.8 percent compared to the previous year, with its strongest business being its core engagement ring pages. However, this is below the average of about 11 percent growth the company has reported in each of the past four years.

	Press reports from China indicate that retail jewelry sales continue to slow from the heady growth of previous years. These year-on-year comparisons of retail results may not accurately reflect the market as last year’s steep drop in the gold price created a buying spree that caused an abnormal spike in sales. However, diamond dealers and manufacturers noted that Chinese retailers have begun trading down on quality to hold the line on prices as consumers there grow more cautious.

AUCTIONS: Consumer reticence does not appear to be having an effect on the extreme top end of the market, as recent jewelry auctions continue to command extreme prices.

	Sales at Christie’s April 19 New York auction totaled $60.6 million. Major items included a pair of GIA-graded round brilliant, D color, Internally Flawless diamonds, a 22.6 carat and 22.31 carat, which brought $8.56 million; and a 40.43 carat, D color, potentially Flawless GIA-graded oval-cut diamond which brought $7.7 million, or nearly $190,000 per carat.

	On April 29, William Doyle Galleries in New York sold a pair of natural drop pearls believed to have been owned by Empress Eugenie of France for a record auction price of $3.3 million. The same day, Sotheby’s New York sold a 28.18 carat Kashmir sapphire for $5.09 million, or $180, 731 per carat, a world record price for such a stone.

	As reported last month, on April 6 in Hong Kong, Sotheby’s sold the jade-bead Hutton-Mdivani necklace for a record $27 million, double its pre-sale estimate and the record auction price for a jadeite jewel. The piece contained 27 “high-translucent” jade beads, ranging from 15.4 to 19.2 mm.

	The week of May 12 will feature two major auctions in Geneva. On May 13, Sotheby’s will offer the 100.09 carat Graff Vivid Yellow Diamond, expected to sell for $15 to $25 million, and the 31.34 carat D, potentially flawless Victory Diamond, which carries a pre-sale estimate of $5 to $8 million.

	On the following day, Christie's will offer a 13.22 carat Fancy Vivid Blue diamond, named “The Blue,” the largest Flawless, Vivid Blue diamond to come up for auction (the 27.64 carat Heart of Eternity is the largest known Fancy Vivid Blue), which it expects to sell for $25 million; and the 5.5 carat Fancy Vivid bluish green The Ocean Dream, the largest vivid blue-green diamond ever to be auctioned. It is expected to bring between $7 and $10 million. @chapter:32 @chapter:3 @chapter:32


# Publication Year: -
# Title: Rare Books Project Puts Gem and Jewelry History Within Reach
# Abstract: Digital Transitions’ BC100 is highly specialized equipment enabling GIA technicians to safely digitize rare works such as this text from 1648 by Ulisse Aldrovandi. Photo by Robert Weldon/GIA

The feeling of responsibility washing over Sarah Ostrye as she carefully turned the book’s pages was “nerve-wracking,” she admits.

Then again, the manuscript in her hands was no ordinary book, but a 516-year-old copy of Pliny’s “Natural History” – the oldest in GIA’s 64,000-volume collection.

Ostrye, a research librarian and digital archivist for GIA’s Richard T. Liddicoat Gemological Library and Information Center, is helping lead the Institute’s multi-year effort to bring thousands of the rarest, most venerated books in gemology, mineralogy and jewelry from the shelves of the library’s Cartier Rare Book Repository and Archives into easy reach of the global community.

To date, more than 200 historically significant books housed in the library have been digitized and made available for free through the nonprofit digital library Internet Archive. The public is responding: since the project was unveiled in July 2015, there has been a steady increase in monthly book views – from 378 views in July 2015 to 1,922 in September 2016.

That’s encouraging news for Dona Dirlam, director of the GIA library and architect of the digitization project.

“We can better serve the public trust by providing these resources,” she says. “The current and future state of gemology and the jewelry industry relies on having in-depth knowledge of our history – it’s the foundation for understanding the science and business of our industry.”

Dona Dirlam, director of GIA’s Richard T. Liddicoat Gemological Library and Information Center, says that an early group of supporters, including Richard T. Liddicoat, Glenn Nord, Kurt Nassau and Bill Boyajian, believed the Library could become “a world-class center for information” for the gem and jewelry industry. “Now, because we can digitize books from this collection, we’re able to bring these precious resources to the global community,” she says. Photo by Emily Lane/GIA
Access for All
What the project aims to do, in essence, is to make it as easy to enjoy an 1817 copy of Sowerby’s “British Mineralogy” with your morning coffee as it is to pick up a newspaper. What once required an appointment and a trip to the Institute’s Carlsbad, California world headquarters now takes a few clicks of the mouse.

Dirlam has spent nearly three decades planning how to expand the reach of the library’s collection, which represents 85 years’ worth of curation on the part of GIA librarians. (The collection’s size increased exponentially when the Institute acquired the John and Marjorie Sinkankas Gemological Library in 1988.)

“Once we had the Sinkankas collection, we began to think about how to provide greater access to it, and to GIA’s existing rare book collection, beyond the physical walls of the library. And one of John Sinkankas’ key desires was to enable as many people as possible access to his life’s work,” Dirlam says. “Because of advances in technology, this project is opening up the reach of this library and providing access to a global audience.”

Dirlam and her team, including library manager Paula Rucinski, consulted with multiple digitization experts through the years, from geoscience librarians to staff at Los Angeles’ Getty Conservation Center. Plans finally crystallized in late 2014 and GIA’s executive team gave its stamp of approval for resources – including the purchase of specialized equipment, and the hiring of Ostrye – in December 2014.

GIA librarians began to reach out to scientists and jewelry industry leaders for recommendations on which books in the library’s collection should be the highest priority for digitization. They added the rarest titles, and only those that were out of copyright.

In addition to Pliny’s encyclopedia – a work that was the foundation of all science until the Renaissance, and one of the largest single works from the Roman Empire to have survived – other early digitized titles include an 1801 copy of Renée Just Haüy’s “Treatise of Mineralogy” and Bishop Marbode’s 1511 treatise, “Book of Precious Stones.” Marbode’s work is the earliest lapidary (book on gemstones) from the Middle Ages, and the first of his works printed on a Gutenberg movable metal type press.

An especially rare, 1925-26 catalog of Russia’s Romanov dynasty’s regalia and crown jewels was the 200th book to be digitized, and gave the public its first look at the 406-piece collection.

The digitization project also ensures that these rare, delicate books are safeguarded for all time.

“We take every precaution to carefully preserve and secure this collection,” Dirlam says. “The Sinkankas Library and other rare books are housed in a temperature- and humidity-controlled room. If a natural disaster, such as a flood or fire, occurred and the books were damaged, however, we have the digital files that capture every word, photo and illustration. These books tell the story of gems and jewels and will be accessible for generations to come.”

GIA research librarians Augustus Pritchett, left, and Sarah Ostrye have digitized more than 200 rare books from the Institute’s collection in the last two years. Photo by Emily Lane/GIA
A Painstaking Process
The digitizing process is a delicate one, full of potential complications for the technicians – including Ostrye and research librarian Augustus Pritchett – who are charged with creating digital files from often-challenging sources.

“Sometimes the text is very close to the gutter of the book, or there is fragile binding, delicate tissue paper overlays, or foldouts that may not fit under the glass platen,” says Ostrye. “Those require extra time and attention.”

The pair takes turns working in a secure room near the Cartier Rare Book Repository and Archives. The room houses a high-tech digitizing machine (Digital Transitions’ BC100 Book Capture system), that makes it possible to gently cradle the books instead of forcing them into a flat, spine-damaging position. Technicians turn each page manually to avoid skipping or tearing them, and capture high-resolution images that they edit and convert to TIFF files. Post-processing software even enables them to create searchable PDFs and e-books regardless of alphabet – including Roman, Cyrillic, Chinese, Japanese and Korean.

Visitors to the site are downloading more and more of the books every month, and Ostrye says it’s helping the library track trends in research.

“Based on which books are viewed the most, we can get an idea of which topics are most popular,” says Ostrye. “Many of our most-viewed books deal with the history of gemstones and jewelry design.”

Dirlam, who says the library will also begin to increase the availability of e-books and e-catalogs, notes that the public is welcome to submit recommendations for books to digitize. It’s one more way the library can engage the trade and public in the project, which she sees as imperative to ensuring the public trust in gems and jewelry.

“It is mission-critical that we preserve the important books, documents and other materials of the global gem and jewelry industry by digitizing them,” she says. “As Marjorie Sinkankas said, ‘We are only caretakers for a short time.’ It is our mandate to see that these materials are cherished and available for generations in the future.” @chapter:28 @chapter:2 @chapter:28


# Publication Year: 2023
# Title: Solid Laboratory-Grown Single-Crystal Diamond Ring
# Abstract: Figure 1. The 4.04 ct ring fashioned from a single-crystal CVD-grown diamond. Photo by Towfiq Ahmed.
Carved single-crystal diamond rings are rare, with few examples to reference (see Spring 2020 Lab Notes, pp. 132–133). But with advancing technology in the laboratory-grown diamond industry, the creation of solid faceted diamond rings is now a reality. Recently submitted to the New York laboratory was a 4.04 ct single-crystal laboratory-grown diamond ring (figure 1). The 3.03 mm thick band had an inner diameter of 16.35–16.40 mm and an outer diameter of 20.32–20.40 mm. The ring was produced by Dutch Diamond Technologies in collaboration with the Belgian jewelry store Heursel, established in 1745.

Figure 2. OpenCV software was used to draw perfect circles from the center of the ring, marked by a green dot. Photo by Towfiq Ahmed.
This laboratory-grown diamond ring was cut from an 8.54 ct plate grown by chemical vapor deposition (CVD). Laser cutting produced a near-perfect circular ring, as demonstrated using digital imaging analysis to measure its inner and outer circumferences (figure 2).
The manufacture of a solid single-crystal diamond ring is a complex and challenging process. Once material is removed from the crystal, very fine fractures and imbalanced strain can have severe consequences, and the ring can shatter. Processing can take more than six months. Creating the ring from a single-crystal laboratory-grown diamond involved about 1,131 hours of processing (including pre-grinding) in the Dutch town of Cuijk, followed by 751 hours of polishing in Belgium.
Infrared absorption analysis revealed it was a type IIa diamond (no detectable nitrogen), and no hydrogen-related peaks were detected at 3107 or 3123 cm–1. Photoluminescence spectroscopy showed interesting vacancy-related defects indicative of a multi-step growth process. A very strong emission from the silicon vacancy (SiV–) defect was observed with 633 nm laser excitation; this is a common feature used to identify CVD-grown diamond. The conclusion was that this ring had not undergone post-growth treatment; nevertheless, it was notable that the ring showed relatively low nitrogen-related defects such as NV centers, along with no detectable 468 nm peak or the 596/597 nm doublet. P. Martineau et al. (“Identification of synthetic diamond grown using chemical vapor deposition (CVD),” Spring 2004 G&G, pp. 2–25) observed the 596/597 doublet with a 514 nm laser. Also of note, there were no H3 or 468 nm centers detected with 457 nm laser excitation.

Figure 3. Strong birefringence observed under cross-polarized light (left) and blue fluorescence observed in the DiamondView (right). Images by Paul Johnson (left) and Madelyn Dragone (right).
Strong birefringence was observed using cross-polarized light under microscopic analysis, with an unusual radial pattern (figure 3, left) signifying unique growth conditions compared to typical CVD diamonds available in the market today. The deep ultraviolet illumination of the DiamondView (figure 3, right) confirmed these unusual growth features with a lack of post-growth fluorescence colors such as green produced by the H3 center.
The solid laboratory-grown diamond ring was studied by GIA and determined to have VVS2 clarity based on dark non-diamond carbon pinpoint inclusions (growth remnants typical of CVD-grown diamonds) with Good polish (polishing on the interior surface of the ring precluded Very Good). Although the ring was a near-perfect circle (figure 2), symmetry was considered not applicable. The diamond had an E color specification based on GIA’s color grading scale. The ring was laser inscribed “Laboratory-Grown” on a side facet.
The quality and size of this solid diamond ring (see the video below) provide a great example of the advancing technology in laboratory-grown diamonds and changing trends in the jewelry industry. This is the first time a GIA laboratory has examined a colorless diamond ring fashioned entirely from a laboratory-grown diamond.

	Solid CVD-Grown Diamond Ring @chapter:36 @chapter:1 @chapter:36


# Publication Year: 2018
# Title: Microlite Crystals in Topaz from Pakistan
# Abstract: Figure 1. A 16 mm topaz crystal and an 8.69 ct faceted topaz, both with microlite inclusions, from Pakistan. Photo by J. Hyršl.

Microlite, NaCaTa2O6(OH), is a typical mineral of highly developed lithium pegmatites, known from many localities worldwide. It always forms yellow to orange octahedral crystals. It was already known as inclusions in quartz from Pakistan (J. Hyršl and G. Niedermayr, “Einschlüsse im ‘Allerweltsmineral’ quarz,” Mineralien-Welt, Vol. 18, No. 2, 2007, pp. 44–55), but much more beautiful are microlite inclusions in topaz (figure 1), examples of which were sold in Tucson in January 2018. Shigar Valley in northern Pakistan was reported as the locality. Both minerals were confirmed by Raman spectroscopy.
Topaz forms loose, very light brown crystals up to about 2 cm, and microlite forms sharp transparent orange octahedrons in sizes up to about 1.5 mm. The inclusions grew both on the surface and inside the topaz crystals (figure 2). Several topaz crystals were faceted, and the stones host some of the most aesthetically pleasing inclusions found during the several last years.

Figure 2. A microlite crystal, measuring 1 mm across, in a topaz from Pakistan. Photo by J. Hyršl. @chapter:15 @chapter:0 @chapter:15


# Publication Year: -
# Title: Aquamarine Journey
# Abstract: Few people outside the gem industry realize the true nature of a gemstone’s journey from the mine to the counter of a store. Whether the gem is being offered to consumer’s at a traditional jewelry store’s counter, an internet shopping site, or a television broadcast the journey always involves a great deal of effort.  Tons of earth and countless hours of labor are needed to being a gem from mine to market. @chapter:38 @chapter:2 @chapter:38


# Publication Year: 2024
# Title: Dubai's diamond trade to reach $38.3 billion in 2023
# Abstract: Dubai and the United Arab Emirates (UAE) play a crucial role in the global diamond and jewelry business due to their advantageous tax policies, robust financial infrastructure, and logistics. The diversity of products and prices, easy accessibility, and genuine support from the government make them pillars for successful businesses across all industries.

The Dubai Multi Commodities Centre (DMCC), overseeing trade, business, and consumer goods for Dubai, disclosed that the total trade value of rough and polished diamonds in Dubai reached 38.3 billion USD in 2566, marking a growth rate of 2% compared to the previous year. This translates to an average Compound Annual Growth Rate (CAGR) of 11.0% over the past five years.

Diamond Trade

In 2566, the total trade value of rough diamonds for the UAE amounted to 21.3 billion USD. Despite a global decrease in rough diamond prices by about 20%, the UAE's rough diamond trade declined by only 13% compared to the previous year. Ahmed Bin Sulayem, the CEO of DMCC, stated that the total trade value of rough and polished diamonds was 8.3 billion USD in the previous year, with polished diamonds accounting for almost half of the total diamond trade. This demonstrates that Dubai is not merely a middleman but has developed infrastructure and technology to enhance market value and attractiveness. The Dubai Diamond Exchange (DDE) is the world's largest diamond trading floor, accommodating at least 200 interested buyers and sellers for auctions and ensuring the highest product quality through specialized equipment for diamond cleaning as per buyers' demands.
Dubai has been supporting the trade of Lab Grown Diamonds (LGDs) or synthetic diamonds, which are created from pure carbon. This involves simulating the natural diamond formation process within a laboratory using state-of-the-art technology. The UAE saw a 10% increase in trade value in 2566 compared to the previous year, totaling 1.6 billion USD. This growth is attributed to the changing preferences of newer generations like Millennials and Gen Z, influenced by global economic fluctuations, societal changes, and environmental concerns. Surveys from various sources globally indicate a growing trend among newer generations to prefer and purchase jewelry made from "synthetic diamonds" produced in laboratories.

In recent years, the UAE has become a key driver in the growth of global diamond trade and industry development. Ahmed Bin Sulayem, representing the UAE, assumed the chairmanship of the Kimberley Process for the year 2567, focusing on the "Year of Delivery" to ensure the efficient and independent functioning of the Kimberley Process. This marks his second term as chairman since 2559.

In 2543, as a measure to eliminate and prevent the trade of diamonds from areas under legitimate government opposition control, an international conference was held to establish guidelines for issuing certificates between countries for diamonds. These measures, known as the Kimberley Process, were established by an international organization comprising all major diamond industry countries, totaling 52 nations. Their objective is to set guidelines and establish a certification system for non-polished diamonds to maintain consistent standards and international acceptance. This helps eliminate and prevent income from unpolished diamond trade originating from areas under legitimate opposition control, which might be utilized for acquiring weapons and warfare equipment, safeguarding the diamond trading industry from potential future repercussions of other measures that could be implemented.

Importing gold, diamonds, and pearls is a lucrative business for the UAE, as evidenced by the latest statistics from UNCOMTRADE, which show imports valued at 91.573 billion USD, accounting for 24.5% of total imports. This sector has experienced a growth rate of 24.0%, with imports primarily coming from the top 10 countries including India, Russia, Turkey, Malaysia, Ghana, South Africa, Switzerland, Belgium, Zimbabwe, and Botswana.

On the export front for Thailand, jewelry and gems sent to the UAE include genuine gold, diamond, and pearl jewelry, sterling silver jewelry, synthetic pearls, and unprocessed gold. In 2566, exports were valued at 265 million USD, declining by 3.7%, and in 2567 (January), the value was 15.5 million USD, declining by 7.9% compared to the same period of the previous year. @chapter:37 @chapter:3 @chapter:37


# Publication Year: 2003
# Title: Red Beryl from Utah: A Review and Update
# Abstract: There is only one known commercial occurrence of gem-quality red beryl in the world: the Ruby Violet (or Red Beryl) mine in the Wah Wah Mountains of Beaver County, Utah. The beryl is found mostly along fractures (often clay-filled) in a topaz rhyolite. It crystallized as a vapor-phase mineral from the reaction between rhyolite-derived gases, vapors originating from heated ground waters, and preexisting minerals and volcanic glass in the rhyolite. Production of red beryl over the past 25 years is estimated to be more than 60,000 carats, of which about 10% was facetable. Exploration and evaluation programs undertaken by two mining companies from 1994 to 2001, combined with field studies by some of the authors and others, have resulted in a greater understanding of the geology of the Ruby Violet deposit and the potential for productive areas beyond the current mine site. @chapter:2 @chapter:0 @chapter:2


# Publication Year: 2003
# Title: Spring 2003 G&G Lab Notes
# Abstract: Diamond with Fracture Filling to Alter Color
Intensely Colored Type IIa Diamond with Substantial Nitrogen-Related Defects
Diamond with Unusual Overgrowth
Euclase Specimen with Apatite and Feldspar
"Cherry Quartz” Glass Imitation
Cat’s-Eye Opal
“Blue” Quartz
Heat-Treated Ruby with a Large Glass-Filled Cavity
Play-of-Color Zircon

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


# Publication Year: 2017
# Title: Book Review: Ruby
# Abstract: By Joanna Hardy, 368 pp., hardcover, illus., publ. by Thames & Hudson, New York, 2017, US$125.00.

With its deep crimson color and bold gold lettering, Ruby stands out on a bookshelf, much as a piece of fine jewelry catches attention in a room. This eye for design continues inside the beautifully laid-out volume, with plenty of examples of important ruby jewelry and the powerful people who have worn them throughout history.

Ruby begins with a section on spinel, which has been confused with ruby in the past. This is a nice touch, because any historical account of ruby would be incomplete without the mention of spinel. Author Joanna Hardy goes on to describe ruby and its properties. However, it must be emphasized that, by the author’s own admission, this book is not meant to be a gemological text. In fact, the gemological information is brief and in places contains minor errors. For example, the fluorescence in rubies is attributed to different levels of chromium without a clear explanation of how iron content has a strong influence on a ruby’s fluorescence and overall appearance.

Hardy’s strength is in talking about rubies’ historical impact and in explaining the significance of prominent pieces of jewelry, and much of the book is devoted to this. The sections cover a wide range, from older royal collections to modern pieces worn by 20th century celebrities such as Grace Kelly and Marlene Dietrich. They provide a wonderful overview of how rubies became a symbol of power and influence. There are numerous illustrations both of the jewels, such as the legendary Nga Mauk ruby, and the people who owned these storied pieces

Following this topic, the book covers some of the techniques used by jewelry designers from the classic houses of Cartier and Van Cleef & Arpels to more contemporary designers like Wallace Chan. Again the author plays to her strengths, sharing insights from her experience as a jewelry expert.

In the final sections Ms. Hardy provides a charming travelogue of her own visits to the world’s most important ruby mines, which she took in preparation for writing this book. I particularly enjoyed following the journey of a ruby crystal sourced from artisanal miners in Mogok, Myanmar (formerly Burma) from rough into a piece of finished jewelry.

Readers should not expect a gemology textbook when purchasing this volume. Instead, it reads like a gorgeously illustrated art history guide. Although Ruby can be read cover-to-cover, it is presented in sections that can stand alone, making it an ideal coffee table book to pick up and read at leisure. I found myself skipping forward to sections that I was most curious about, which works well with the format.

This luxurious tome will broaden your gemological background, explaining the historical and cultural impact of ruby and how it has earned its title as the king of gems. It would make a wonderful gift for anyone with an interest in ruby, and an especially nice accompaniment to a piece of ruby jewelry. @chapter:28 @chapter:2 @chapter:28


# Publication Year: 1996
# Title: De Beers Natural versus Synthetic Diamond Verification Instruments
# Abstract: Two instruments have been developed at De Beers DTC Research Centre, Maidenhead, to distinguish synthetic diamonds from natural diamonds. The DiamondSureTM enables the rapid examination of large numbers of polished diamonds, both loose and set in jewelry. Automatically and with high sensitivity, this instrument detects the presence of the 415 nm optical absorption line, which is found in the vast majority of natural diamonds but not in synthetic diamonds. Those stones in which this line is detected are "passed" by the instrument, and those in which it is not detected are "referred for further tests." The DiamondViewTM produces a fluorescence image of the surface of a polished diamond, from which the growth structure of the stone may be determined. On the basis of this fluorescence pattern—which is quite different for natural as compared to synthetic diamonds—the trained operator can positively identify whether a diamond is natural or synthetic. @chapter:36 @chapter:1 @chapter:36


# Publication Year: 2014
# Title: Books: Rings – Jewelry of Power, Love and Loyalty
# Abstract: By Diana Scarisbrick, 384 pp., illus., publ. by Thames and Hudson, London, 2014, $34.95.

              If you’ve ever uttered the words, “I think I’ll wait till it comes out in paperback,” your ship just came in. I’ve said it myself, numerous times, and then forgotten all about whatever book I was waiting for. Not this time.

Originally published as a hardcover in 2007, Rings: Jewelry of Power, Love and Loyalty is the real deal. It is brilliantly photographed, meticulously researched, and engagingly readable, with a high-quality paperback binding, sewn pages, and a double foldout cover. At $34.95, you can’t afford not to own this treasure.

Perhaps my favorite feature of this book is simply that it contains multiple images of many of the subjects. How often do you see the top view of a ring and wonder what a side detail looks like? Or you might have a perfectly acceptable perspective view, yet the text describes an engraving on the inside of the band that is not shown in the image. Kudos to Scarisbrick and the photographer for taking the time to include these creative angles. What a luxury.

The heart of the book is the Benjamin Zucker Family Collection, accompanied by pieces from the Walters Art Museum in Baltimore, the Museum of Fine Arts in Boston, Rosenborg Castle in Copenhagen, London’s Freud Museum, the Cartier Collection, and a host of private collections.

The organization of information in Rings is a treat. It is arranged into eight thematic chapters, each explored chronologically from ancient times to the present. With this format, you can see the evolution of certain types of rings, and how art, fashion, politics, and social norms exerted their influences. Starting with 50 pages of signets in the first chapter, all of the sections provide insightful ways to associate and characterize the groupings of rings.

The remaining chapters parse the vast oeuvre of rings into what might be considered sociological subdivisions, such as “Love, Marriage, and Friendship Rings,” “Rings Associated with Illustrious People and Great Events,” “Decorative Rings,” and so on. I am fascinated to see how the ring, a relatively small item, can open up insights to so many different time periods and how the popularity of different types of rings waxed and waned.

Adding to the depth of information in each chapter is the use of drawings and paintings from various periods. Scholarly but not stuffy, the background text fleshes out the humanity behind the rings and adds insights about the people and the times. Equally impressive is the technical mastery of countless, mostly anonymous, jewelry makers. We see examples that may have been solo efforts, as well as numerous collaborations between designers, goldsmiths, lapidaries, stone setters, enamelists, and polishers. All come together to create a lasting, wearable work of art, the perennially popular ring. @chapter:25 @chapter:2 @chapter:25


# Publication Year: 2017
# Title: Book Review: Secrets of the Gem Trade, Second Edition
# Abstract: By Richard W. Wise, hardcover, 404 pp., illus. publ. by Brunswick House, Lenox, Massachusetts, 2016, $99.95.

The gem and jewelry industry is still extremely secretive, even in our fast-paced digital era. In both the first and this second edition of Secrets of the Gem Trade, Richard W. Wise targets trade secrets that almost all beginners and consumers would like to peek into. With over 30 years of experience in the industry, Mr. Wise shared both his knowledge and life experience with his readers in this marvelous work.

Since Wise was not born into the trade—he started out as an apprentice goldsmith, becoming a well-known gem businessman—his personal experience will echo with many readers of this book. His book has been expanded since the first edition was published in 2002. The second edition builds on the author’s research and personal excursions to gem sources, manufacturer hubs, and major markets around the globe. This effort is well reflected in the sophistication of content in many chapters. Wise incorporates important, newly discovered gem sources, including East African ruby deposits. Wise also provides updates on sources that used to be important but have since been exhausted. As a result, the author almost completely rewrote the ruby, sapphire, and spinel chapters in order to deliver the most updated information to the readers.

Wise also added chapters on jade, natural nacreous pearls, conch pearl, demantoid garnet, peridot, moonstone, and sunstone. There is also an introduction to go together with each of the above gems (with the exception of demantoid garnet). A new introduction of blue white diamonds was also included with this update. I paid special attention to the new jade chapter, as Wise went to China’s jade manufacturing centers to experience their treatment of this gem in person.

The first seven chapters of the book introduce the essentials of connoisseurship. The discussion begins with the history of the precious gem concept and the modern concept in comparison. Then it moves to the address several pillars of the modern gem and jewelry industry including grading standards, color description, grading special cases, gemstone enhancement and an overview of new gem sources. Beginning with chapter 8, each chapter deals with one specific gem variety. For gems falling into the same group, the author also provides an introduction before providing an in-depth look at each material. For example, there is an introduction for pearls which is followed by four separate chapters devoted to different varieties.

While this book can be used as a gemology textbook, it is also quite different than those traditionally used for this purpose. The order of the chapters on individual gem varieties follows the alphabetic sequence rather than mineral classification. This makes it a lot easier for readers with no mineralogy background to navigate. Second, the author uses understandable language, rather than scientific terminology, to deliver the message to readers of all different levels and interests. When explaining concepts, personal understanding is always described to add the author’s personality to the content. For instance, in the “Rethinking of 4Cs” chapter, the author explained the standardized 4Cs and then added his own 5th C, “crystal,” an interesting concept that people won’t be able to find in gemology textbooks. Last but not least, this book is well illustrated with breathtaking images and deliberately designed graphics, an aspect that is often lacking in conventional gemology textbooks.

Readers will not just learn the essential concepts of modern gemology, but will also get a better understanding of the gem market. Additionally, the author also uses his own experience to tell the readers what is the best way to learn the gem trade, giving and what “homework” they need to do before going out to buy. It is a good read for people who are currently outside of the trade but want to step in. It is also an excellent review for those who are already experienced in this trade. The second edition of Secrets of the Gem Trade is definitely one of the best comprehensive gemological publications you can find today. @chapter:33 @chapter:2 @chapter:33


# Publication Year: 2018
# Title: Unusual Orange Pyrope-Spessartine-Grossular Garnet
# Abstract: Figure 1. The unique composition of this 7.97 ct orange pear-shaped garnet was revealed as pyrope-spessartine-grossular. Photo by Robison McMurtry.

GIA’s New York laboratory recently examined an orange pear-shaped faceted stone (figure 1). Standard gemological testing revealed a refractive index of 1.771 and a hydrostatic specific gravity of 3.89. The fluorescence reaction was inert to long-wave and short-wave UV light. The stone did not show any pleochroism when viewed with a dichroscope. Using a handheld spectroscope, absorption bands located at 410 and 430 nm in the blue and violet sections were clearly observed. All of these gemological properties are consistent with pyrope-spessartine garnet based on the classification system from Stockton and Manson (“A proposed new classification for gem-quality garnets,” Winter 1985 G&G, pp. 205–218).

Besides standard gemological testing, all garnets submitted to GIA laboratories are routinely analyzed by energy-dispersive X-ray fluorescence (EDXRF) spectroscopy (see column 4 of the supplementary table below). EDXRF results showed that the stone was predominantly composed of 15.37 mol.% pyrope, 53.70 mol.% spessartine, and—surprisingly—25.39 mol.% grossular. Unlike normal pyrope-spessartine garnet submitted to GIA that contains a small amount of grossular (less than 10 mol.%), this garnet had a much higher grossular component that had never been reported before in gem-quality garnets, to our knowledge. (Note that “malaia/malaya” is a trade name for yellowish, reddish, or pinkish orange pyrope-spessartine garnets that can potentially contain 2–94% spessartine, 0–83% pyrope, 2–78% almandine, 0–24% grossular, and 0–4% andradite. The garnet we examined falls into this concentration range.)

To validate the accuracy of the chemistry, we performed laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) analysis using a Thermo Fisher iCAP Qc ICP-MS coupled with a New Wave Research UP-213 laser ablation unit to obtain an additional set of chemical composition. USGS glass standard GSD-1G and GSE-1G were used as external standards. 29Si was used as internal standard. The LA-ICP-MS results showed good agreement with the EDXRF results (see columns 1–3 of the supplementary table above).

Figure 2. (Pyrope + grossular)-spessartine-almandine ternary diagram with data points based on molecular percentages for pyralspite garnet (modified after Stockton and Manson, 1985). The orange spot is the average of three sets of LA-ICP-MS data (table 1, columns 1-3). Refractive index and spectral boundaries are used to distinguish among the six proposed garnet species labeled in the diagram.
Garnets are a group of isometric nesosilicates with the general chemical formula X3Y2Z3O12. Natural rock-forming silicate garnets are commonly divided into the pyralspite (pyrope, almandine, and spessartine) and ugrandite (uvarovite, grossular, and andradite) groups. In pyralspite, Al3+ occupies the Y-site and the X-site may contain Mg2+, Fe2+, or Mn2+; these garnets are composed predominantly of pyrope (Mg3Al2Si3O12), almandine (Fe2+3Al2Si3O12), and spessartine (Mn3Al2Si3O12) end members. Stockton and Manson (1985) presented a ternary plot (figure 2) to gemologically classify the pyralspite garnet species, and this showed the correlation among refractive index, visible spectroscopic observation, and chemistry. They determined that pyrope-spessartine should have a refractive index between 1.740 and 1.780 along with clear 410 and 430 nm absorption bands. We concluded that the orange pear-shaped garnet should be classified gemologically as pyrope-spessartine garnet.

To understand why this garnet with a high grossular component still shows the same gemological properties of normal pyrope-spessartine, we plotted the orange garnet chemistry in this ternary plot by combining pyrope with a grossular component. The orange spot representing the orange garnet appeared in the pyrope-spessartine region, because the refractive index of pure pyrope (1.714) is close to and functions almost the same as the RI of pure grossular (1.734) in contributing to the combined refractive index. Since there is not a specific gemological species name for this orange garnet with higher grossular than pyrope component, the authors suggest that the stone be called pyrope-spessartine-grossular. This case demonstrates that sophisticated chemical analysis of garnet should be practiced routinely in gemological laboratories to make sure unique garnets are not misidentified. @chapter:13 @chapter:0 @chapter:13


# Publication Year: 2018
# Title: Freshwater Pearls, Blister and Loose, with Their Host Shells
# Abstract: Figure 1. Three freshwater pearls attached to their host shells. Left to right: A blister pearl measuring approximately 37.45 × 27.48 mm, a loose wing pearl measuring 35.82 × 9.37 × 5.94 mm and weighing 10.60 ct, and a blister pearl measuring approximately 23.60 × 19.49 mm. Photo by Sood Oil (Judy) Chia; specimens courtesy of Mississippi River Pearl Jewelry Co. LLC.
GIA occasionally receives blister pearls attached to their host shells for identification (Winter 2015 Lab Notes, pp. 432–434; Summer 2017 Lab Notes, pp. 231–232), which can provide helpful information on the overall growth conditions and the mollusk species. Recently the New York laboratory had an opportunity to study three freshwater specimens: two blister pearls still attached to their shells, and one loose “wing” pearl that was reportedly found in the shell with which it was submitted (figure 1).
While approximately 1,000 species of freshwater mussels have been identified worldwide, the United States alone is said to host about 300 species, compared to 96 species in Africa, 60 in China, and 12 in Europe (Virginia Department of Game and Inland Fisheries, 2018, https://www.dgif.virginia.gov/wildlife/freshwater-mussels/). The number of U.S. species shows the spectacular diversity of its freshwater resources. Hence, it proves how difficult it can be to apply correct zoological names to specific shells. However, experienced local fishermen who harvest the mussels are often the source of helpful information (T. Hsu et al., “Freshwater pearling in Tennessee,” 2016). The owner claimed that the loose wing-shaped pearl (figure 1, center) was found in a Potamilus purpuratus “Bluefer” mussel in a U.S. river. Bluefer mussels exhibit a pinkish purple to deep purple nacre lining and can produce pearls of a similar color range. Energy-dispersive X-ray fluorescence (EDXRF) spectrometry confirmed that it originated from a freshwater environment, based on its chemistry result of more than 1000 ppmw manganese. Freshwater pearls usually show higher than 100 ppmw manganese content. Real-time X-ray microradiography (RTX) revealed a natural growth structure, while Raman spectroscopy detected aragonite and polyenic peaks, the latter indicating the presence of natural coloring pigments (S. Karampelas et al., “Role of polyenes in the coloration of cultured freshwater pearls,” European Journal of Mineralogy, Vol. 21, 2009, pp. 85–97). This specimen also displayed the characteristic elongated, flat, and slightly curved shape characteristic of wing pearls that, as the name implies, resembles the shape of a bird’s wing. Wing pearls commonly form in the hinge area within shells, and it was interesting to see a similar-sized cavity in the shell submitted with this pearl.
The other two blister pearls were also claimed to have originated from a freshwater environment, and this was confirmed by their optical X-ray fluorescence reactions. Both specimens showed a strong yellowish green luminescence under X-ray excitation, a result that agrees with pearls from a freshwater environment due to their higher manganese content (H.A. Hänni et al., “X-ray luminescence, a valuable test in pearl identification,” The Journal of Gemmology, Vol 29, No. 5/6, 2005, pp. 325–329). According to the owner, the smaller shell (figure 1, right), possibly a washboard mussel (Megalonaias nervosa), was found in a U.S. river, while the larger shell (figure 1, left) is likely a hybrid Hyriopsis mussel commonly used by cultured pearl farmers in China. Blister pearls form when a whole pearl within the connective tissue breaks through the mantle due to its size and/or weight, or for some other reason, and presses against the nacreous inner surface of the shell, where subsequent nacre deposition fuses the pearl to the shell (E. Strack, Pearls, Ruhle-Diebener-Verlag, Stuttgart, Germany, 2006, p. 124).

Figure 2. Close-up images of the freshwater blister pearls from China (left) and the United States (right) attached to their hosts. Photos by Joyce Wing Yan Ho.

Figure 3. The RTX structure of the large blister pearl (shown on the left in figures 1 and 2) revealed a void-like structure in which a near-oval feature is visible (indicated by the arrow).
The size of these two blister pearls is impressive, and both protrude conspicuously from the shell while still attached to their hosts (figure 2). The RTX results of the smaller blister pearl revealed concentric growth arcs proving its natural origin. However, the RTX results of the larger blister pearl revealed a void-like structure that may be found within natural and non-bead-cultured pearls, but a near-oval feature inside the void is uncommon in natural pearls (figure 3). GIA gemologists believe this oval feature was the triggering mechanism that likely resulted in the formation of the blister pearl. Whether this oval feature is a by-product of pearl culturing or a natural formation is hard to prove without examining the blister pearl thoroughly in other orientations, which was precluded by its size and position. While the identification of some freshwater pearls remains challenging, these known freshwater samples together with their host shells serve as useful references for laboratory gemologists. @chapter:11 @chapter:4 @chapter:11


# Publication Year: 2014
# Title: Color-Change Garnet in Diamond
# Abstract: Figure 1. This inclusion, a color-change pyrope-spessartine garnet crystal in diamond, appeared grayish green in fluorescent light (left) and purplish red in incandescent light (right). Photomicrographs by Meenakshi Chauhan; field of view 2 mm (left) and 3 mm (right).

The Indian Gemological Institute’s Gem Testing Laboratory recently examined a 0.30 ct colorless round brilliant-cut diamond containing an interesting inclusion. Infrared spectroscopy revealed features found in type IaA diamond, with a slight absorption peak due to hydrogen impurities. With a clarity grade of SI2, the diamond contained several colorless crystals and one surface-breaking grayish green crystal (figure 1, left). Under incandescent light, the grayish green crystal appeared purplish red (figure 1, right), displaying a strong color-change phenomenon.

Under the Chelsea filter the inclusion showed a bright red reaction, suggesting the presence of chromium. There was a polished area of the included crystal on the surface, but it was too small for us to measure the refractive index.

The included crystal did not display pleochroism under microscopic observation with crossed polarizers. Viewed in immersion, it appeared to be singly refractive. DiamondView imaging showed the fluorescence pattern of growth planes found in natural diamond (figure 2). Typical octahedral growth zones of blue N3 fluorescence were evident, with no disturbance in the zones around the color-change crystal.

Figure 2. This DiamondView image of the host diamond shows octahedral growth zones (notice the crystal inclusions). Image by Meenakshi Chauhan.
For conclusive identification of the inclusion, we sent the diamond to the Gem Testing Laboratory in Jaipur for laser Raman spectroscopy. As the color-change crystal broke through the diamond’s surface, a clear Raman spectrum could be obtained (figure 3). The peak at approximately 1332 cm–1 is assigned to diamond, and the peaks at approximately 1046, 910, 858, 637, 549, and 362 cm–1 are assigned to garnet. The 910 cm–1 peak is associated with the pyralspite isomorphous series, which is comprised of pyrope, almandine, and spessartine garnet. The inclusion was therefore identified as garnet belonging to the pyralspite series.

Figure 3. The Raman spectrum of the color-change pyrope-spessartine garnet inclusion  showed the 1046, 910, 858, 637, 549, and 362 cm–1 peaks assigned to garnet. The 1332 cm–1 peak is assigned to diamond. @chapter:22 @chapter:1 @chapter:22


# Publication Year: 2015
# Title: Violetish Blue Spinel in Yellow Sapphire
# Abstract: This violetish blue inclusion in a Sri Lankan yellow sapphire was identified as spinel. Photomicrograph by Nathan Renfro; field of view 5.63 mm.

	Spinel as an inclusion in sapphire has been previously documented in blue and yellow sapphires from Sri Lanka (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Vol. 1, ABC Edition, Zurich, 1986, pp. 353–354). Typically these inclusions are green zinc-rich ghanospinels. Recently the authors examined a transparent light yellow sapphire crystal with a prominent violetish blue octahedral inclusion. Interestingly, microscopic examination showed the violetish blue inclusion to be an intergrowth of at least two gemmy crystals, with the larger one crystallographically aligned with negative crystals that were also present in the host.

	When further examined with polarized light, the violetish blue inclusion appeared to be singly refractive, which meant spinel was a possibility, considering their similar formation environments. The sample was polished down to a plate in order to place the violetish blue inclusion closer to the surface for Raman analysis, which conclusively confirmed that it was spinel. Also present in this sapphire were numerous carbon dioxide–filled negative crystals, fingerprints, and open cracks. The presence of the intact CO2 inclusions and the pristine condition of the spinel inclusion provided clear evidence that the sapphire host had not been subjected to any form of heat treatment. This is the first example of a violetish blue spinel inclusion in sapphire that the authors have examined. @chapter:24 @chapter:0 @chapter:24


# Publication Year: 1985
# Title: Summer 1985 Gem News International
# Abstract: Diamonds
            Africa: Exciting New Diamond Find in Guinea; Kimberley Diamonds Dated
            Australia: Production at Argyle Mines Declines
            Canada: Exploration Scheduled in British Columbia
            China: “Exceptionally Beautiful” Diamonds Discovered
            U.S.: Anomalous Diamond Found in Alaska
Precious Metals
            Alluvial Gold Located by Geological Survey of India
            Bacterial Gold Mining Proposed in British Columbia
            Development of Bolivian Placer Gold Deposits Planned
            Gold and Silver Exploration in Guatemala
            Saudi Arabian Gold Mining
Synthetics and Simulants
            Method for Coating with Synthetic Diamond
            New Man-Made Materials Developed
            Plastic Scrimshaw
Announcements
            Hong Kong Jewelry & Watch Fair Scheduled for September 10-13, 1985
            European Conference on Precious Stones Scheduled for October 18-21 in Antwerp
            Munich’s INHORGENTA 86 Fixed for February 7-11, 1986
            Judy Evans of Minneapolis Wins 1985 Schuetz Jewelry Design Contest
            L.A. County Museum of Natural History unveils “Gemstones and Their Origins”

To view the full section, download the PDF above. @chapter:34 @chapter:3 @chapter:34


# Publication Year: 2000
# Title: Gem Localities of the 1990s
# Abstract: The past decade saw growth in gem exploration, production, and marketing worldwide. Important colored stone–producing regions included: Southeast Asia (Myanmar, Thailand, and Vietnam), Africa (Tanzania, Kenya, Zimbabwe, Nigeria, and Namibia, as well as Madagascar), South America (Brazil and Colombia), central and southern Asia (Sri Lanka, India, Afghanistan, Pakistan, Russia, and China), and Australia. The major sources for diamonds were Australia, central and southern Africa (Botswana, South Africa, Namibia, Angola, and Zaire), and Russia (mainly in the Republic of Sakha), with exciting discoveries in northern Canada. Cultured pearls from French Polynesia, Australia, and China became increasingly important, as production from Japan declined. This article provides a comprehensive overview of those gem deposits that were either new or remained commercially significant in the last decade of the 20th century.

	DATA DEPOSITORY

Pearl Localities Table - Expanded Version
	Submitted by Dona Dirlam
	January 29, 2001 @chapter:21 @chapter:0 @chapter:21


# Publication Year: -
# Title: Hong Kong Report:The Sky Stays Aloft
# Abstract: The annual Hong Kong Jewellery & Gem Fair, which took place in September 2013, is the largest jewelry trade show of its kind in the world. Photo by Russell Shor.

                      Business at the September 2013 Hong Kong show, while spotty, helped lift the spirits of diamond and jewelry manufacturers worldwide.

Exhibitors at the world’s largest jewelry trade fair had prepared for a very poor show because of the slowing Chinese economy and the declining currencies of key Asian nations, including India, Japan, and Malaysia. Worse yet, many diamond manufacturers feared that Indian diamond merchants who have been facing a liquidity crisis would come to the show offering deep discounts to raise quick cash.

To the relief of the trade, exhibitors held relatively firm on prices and Asian retailers, who were low on inventory, came to the show to restock. In general, buying was very cautious. Retailers did not venture far beyond what they needed for the Golden Week holiday in October and the Lunar New Year, which begins January 31.

Diamond demand centered on commercial-quality goods between 0.25 and 0.75 ct and better-quality stones between 2 and 3 ct. While retailers bargained hard on prices, they needed inventory and, in the end, made deals.

Diamond manufacturers reported there was less wrangling over prices at this year’s show because they had little room to maneuver.

“With rough prices still high, margins have been extremely thin, so we could not go much lower on prices,” said one large manufacturer who said he was generally satisfied with the results of the show.

Buyers and exhibitors alike were worried about the persistent rumors of undisclosed melee-size CVD synthetic diamonds entering the market. No one interviewed for this report said that such concerns would curtail their buying at the show, but exhibitors worried that the possibility might depress prices in the future, or until there is an economic means of testing small diamonds.

Emerald dealers reported that demand was up from last year, despite higher prices for the best goods. At the same time, the strong rise in prices for both untreated and heated-only blue sapphire has helped drive demand for tanzanite, particularly because dealers were showing larger amounts of fine-color material this year.

There was much more ruby available than in previous years, as the production from Mozambique has entered the market in a big way. Prices were rising despite the increased supply, said dealers, because the market is recognizing Mozambique as a quality source.

The jade market remained tight because Chinese customs has impounded a number of rough shipments from Myanmar this year. This has caused the Myanmar government to cancel several major auctions.

Pearl dealers reported that demand has improved across every price range and that prices have stabilized after several years of steady declines in all but the very top qualities. @chapter:37 @chapter:3 @chapter:37


# Publication Year: -
# Title: Update on Rock Creek Sapphire Deposit
# Abstract: Figure 1. Excavators and a washing plant on Gem Mountain process gravel for sapphire recovery. Photo by Warren Boyd.

                      Recently, Montana-based Potentate Mining LLC secured approximately 3,000 acres of sapphire-bearing ground covering the famous Rock Creek sapphire district, including the Gem Mountain sapphire mine, near Philipsburg, Montana. Since the discovery of these sapphire deposits in the 1890s, this is the first time that one company has consolidated such a large land position, encompassing the old alluvial sites as well as the area on the hills in between these old workings (figure 1). Potentate has assembled a team of highly experienced placer miners, geologists, mining engineers, and heavy equipment operators to recover and process the sapphires from this mine.

The Rock Creek district sapphire deposits occur in debris flow, colluvium, and secondary alluvial deposits (figure 2). Although the bedrock for these deposits has not yet been defined, Potentate plans further geological mapping and geophysical surveys in the near future to uncover these sources.

Figure 2. A trench on Gem Mountain showing the sapphire-rich colluvium on the hilltops between the previously worked gulches. Photo by Keith Barron.
To date, the rough sapphires recovered from the bulk sampling pits range in size from 0.25 ct to over 20 ct. Approximately 15% of this rough occurs naturally in marketable colors, including pink, orange, orange-pink, lavender, golden yellow, blue-green and green, and fine blue (figure 3). A substantial percentage of the remaining rough responds very well to heat treatment technologies that improve clarity and turn greenish and grayish rough to desirable colors such as blue, orange, yellow, pink, and parti-color.

	Figure 3. A selected assortment of unheated rough sapphires from the Rock Creek deposit
	weighing from 0.50 to 17 ct. Photo by Warren Boyd.
The high-grade concentration of the sapphires recovered from the various test pits, and the substantial inferred rough sapphire resource on Gem Mountain, indicate that Potentate would be able to provide a long-term, consistent supply of sapphire rough to the global market (figure 4). Potentate would be the only large-volume source for the Rock Creek sapphires. The company is developing a marketing strategy that would provide sustainable supply chain guarantees to their clients. These clients including wholesale gemstone cutters, polishers, and fine jewelry retailers would in turn be able to provide guarantees of origin and the presence (or absence) of any heat treatment to their consumers.

	Figure 4. A selection of natural and heat-treated Rock Creek sapphire ranging from 0.50
	to 4.70 ct. Photo by Jeff Scovil. @chapter:21 @chapter:0 @chapter:21


# Publication Year: 2013
# Title: From a Snowflake to an Iceberg: The McFerrin Collection
# Abstract: The McFerrin’s have one of the largest private collections of Fabergé objects and the exhibit contains over 350 items from their collection. This book was published on the occasion of the exhibition “Fabergé: A Brilliant Vision,” part of the McFerrin Collection at the Houston Museum of Natural Science.

In addition to descriptions and provenance of the items on display, this work contains essays on: the history of Peter Carl Fabergé and his businesses in St. Petersburg and Moscow, as well as of the Romanov family; the meaning and significance of imperial awards, gifts and objects; and Fabergé’s jewelry, animal and flower carvings, picture frames, fans, parasol and cane handles, eggs, bell pulls, cigarette cases, and more. There is also some information on designer Alma Pihl and his workmasters. Of course, this all accents the book’s wonderful photography.

The McFerrins’ belief in education and sharing their knowledge is mirrored by the book’s contributors, whose essays are each accompanied by a bibliography and provenance.

Reviewed by GIA Library Staff
Carlsbad, California @chapter:25 @chapter:2 @chapter:25


# Publication Year: 1987
# Title: A Study of the General Electric Synthetic Jadeite
# Abstract: The gemological properties of synthetic green and lavender jadeite, which has been manufactured by the General Electric Company on an experimental basis, are summarized. The synthetic jadeites examined appear as flattened or rounded disks that have indices of refraction of about 1.66 and specific gravities of 3.28-3.34. They are also similar in many other respects to natural jadeites, except for a slightly greater hardness (-8) and differences in luster, translucency, and appearance. The synthetic jadeites are the result of an experimental study, and at present there are no plans for commercial production. @chapter:46 @chapter:0 @chapter:46


# Publication Year: -
# Title: GIA Team Documents Oregon’s Sunstone Mines
# Abstract: The rich glow of red from inside this rough Oregon sunstone hints at its potential as a fashioned gem. Photo by Duncan Pay/GIA.

In July 2013, GIA’s Shane McClure, director of West Coast Identification Services in the Carlsbad lab; Duncan Pay, editor-in-chief of Gems & Gemology; and Robert Weldon, manager of photography and visual communications, traveled with videographer Kevin Schumacher to the remote southeast corner of the U.S. state of Oregon to visit three of the region’s sunstone mines. The team spent five days interviewing the miners and photographing/filming each mining operation. They also collected gem and rock samples for future research, which will be published in Gems & Gemology.

The unique nature of the gems and the harsh, yet beautiful high plains and desert landscape left an indelible impression on all the trip’s participants.

“The contrast between the tall trees at the Ponderosa and the broad, wide valleys and dark rolling volcanic hills near Plush was striking, although both areas have a rugged, distinctive beauty of their own,” Schumacher said.

John Woodmark of the Ponderosa Mine couldn’t agree more, which is why he and his team work so hard to protect it.

“It’s a pristine area, it’s beautiful,” he said. “It’s wonderful just to come up here, let alone find a truly exotic gem like Oregon sunstone. We’ve got over a million board feet of huge ponderosa, most of them in the 250- to 300-year-old range, and we’re trying very hard not to disturb any of those trees and still get the same stones that we need to mine.”

Sunstone is a rare and exotic American gem. That’s what makes mining more than a commercial activity for the people GIA met on this trip, Schumacher said.

“It’s a passion, and a way of life ‒ they’re working hard to make Oregon sunstone a mainstream gem, one that enlightened consumers will ask their jewelers for. I’d never given much thought to sunstone before, but now I realize it’s a genuine treasure ‒ right on our doorstep.”

See the Field Report on Oregon sunstone in the Fall 2013 issue of Gems & Gemology, which includes Schumacher’s videos of mining activities and conversations with the dedicated souls that mine Oregon’s beautiful state gem.

A miner shows the GIA team the production from one of the sunstone mines visited. Photo by Duncan Pay/GIA. @chapter:34 @chapter:0 @chapter:34


# Publication Year: -
# Title: The Hidden Beauty of Gemstones
# Abstract: View Gallery

Gemstones are stunning to behold, yet there’s a world of breathtaking beauty invisible to the naked eye.

Using powerful microscopes and cameras, GIA researchers have photographed numerous gemstones at magnification up to 1,000 times larger than seen with the unaided eye (this magnification would be notated as 1000x). GIA researchers like John Koivula, a pioneer in the field, have used photomicrography to document inclusions in gems. These gemological “fingerprints” tell the story of a gemstone and often reveal if a stone is natural, synthetic, or treated.

Photomicrography has another benefit. Since gem minerals have a high degree of transparency, they serve as geological time capsules. By documenting inclusions contained in them with photomicrography, geologists can study the genetic environment in which a mineral grew. Sometimes this reveals the part of the world where a gem originated. Photomicrography serves invaluable scientific purposes. It also makes for absolutely stunning images.

			GIA education uses photomicrographs to illustrate inclusions. These reference photomicrographs help students determine if a stone they are examining is natural, treated, or synthetic.

			Nathan Renfro, lead analytical specialist, Laboratory Identification Services, GIA @chapter:27 @chapter:0 @chapter:27


# Publication Year: -
# Title: Lapis Lazuli History and Lore
# Abstract: For centuries, Afghanistan has been an important source for top-quality lapis.

                      Historians believe the link between humans and lapis lazuli stretches back more than 6,500 years. The gem was treasured by the ancient civilizations of Mesopotamia, Egypt, China, Greece, and Rome. They valued it for its vivid, exquisite color, and prized it as much as they prized other blue gems like sapphire and turquoise.

Badakshan, a province in present-day Afghanistan, is a forbidding wasteland of mountains, bare of any vegetation. The sheer mountain faces rise as high as 17,000 feet, and are scored with treacherous ravines. Humans make their way there to seek one thing only: the azure treasure that is fine lapis lazuli.

	The miners’ supplies have to be brought into the desolate area by mule train. - Gary
	Bowersox
The same was true as far back as 700 BC, when the region was part of a country known as Bactria. The lapis mines that were producing then are still producing today. They are, in fact, the world’s oldest known commercial gemstone sources.

	The ancient mines of Bactria—now Afghanistan—are still producing lapis today. This
	fine-color specimen was named "The Owl" because of its distinctive shape. It weighs
	about 2 lbs. (1 kg).- Robert Weldon, courtesy M. Chung
Merchant caravans transported their precious blue cargo across Bactria, on their way to the great cities of the ancient Greeks, Indians, Egyptians, Mesopotamians, and Persians. Marco Polo referred to the area’s lapis mines in 1271, but few outsiders have seen them because of their inhospitable location.

For thousands of years, lapis has been fashioned to show off its rich, dark color. Typically, lapis used in jewelry has been cut into cabochons, beads, inlays, and tablets. But lapis lazuli’s use has never been limited to jewelry alone. It’s also a popular carving material. Throughout its history, lapis has been fashioned into practical objects, including game boards, bowls, dagger handles, hair combs, and amulets.

	This lapis cabochon features the ancient symbol of a scarab beetle carved into its surface. - Maha Tannous

	Inlay, a typical lapis cutting style, is featured in this man’s ring. The gold mounting complements the pyrite flecks in the inlay. - Mike Havstad

	Throughout history, lapis has been fashioned into ornamental objects. This elaborate
	carving takes advantage of the striking contrast between light-colored calcite and the
	deep blue of lapis.
Today, lapis is frequently fashioned into freeform and nature-themed sculptures. Some of these carvings become wearable art, others are purely decorative.

	This striking tiger brooch is a creation of Cartier, New York, the famed design house. Its dramatic appearance features yellow diamonds, black onyx, lapis lazuli, and platinum. - GIA and Harold & Erica Van Pelt, courtesy Ishaia Trading Corp., New York.

	This delicate carving is part of the 21-piece “Symphony in Gemstones” collection. - Robert Weldon, gift of Art Sexauer @chapter:31 @chapter:2 @chapter:31


# Publication Year: -
# Title: Bench Tip #7: A Modified Tool to Bezel-Set Round Faceted Stones
# Abstract: Bezel-set round faceted stones

This is a follow-up to Bench Tip #6, “Using a Split Mandrel for Finishing Fabricated Round Bezels,” which showed you how to modify a standard split mandrel to make an effective holding device to finish several fabricated bezels of the same dimensions. The same split mandrel can also be adapted into an efficient tool for setting multiple round faceted stones into those bezels.

Secure the modified split mandrel in a ring clamp. Insert a 3.5 mm ball bur into the No. 30 hand piece of a flex shaft and burr a hollow into the top center of the mandrel, cutting to a depth of about 2.0 mm. Follow with a 2.5 mm ball bur, centering and burring to a total depth of around 3.0 mm. You will create a void that provides clearance for the pavilion and culet of each stone to be set.

	Further modification of the split mandrel for setting is required. Using two ball burs, create a clearance for the pavilion during setting.
The total depth of the bezel must be at least 4.0 mm to accommodate the depth of the stone when set. Choose a finished bezel and position it on the mandrel. Secure the mandrel in a ring clamp. Measure the stone to be set and select the proper size setting bur. You will be cutting the depth of the bearing so that the top of the bezel flange is no less than 50 percent of the crown height. Cut the bearing and check the fit of the stone to make sure it is level and at the correct depth for setting.

	The depth of the bearing should be 50 percent or more, depending on the cut and proportions of the stone.
Remove the mandrel and bezel from the ring clamp and tighten it in the hand piece on your flexible shaft. While spinning the hand piece, use a file to bevel and reduce the thickness of the bezel flange. Clean any debris from the bezel and place a small amount of wax in the bearing to help hold the stone during the setting process. Pack and level the stone.

The bezel contact should be no less than 10 percent of the crown distance, which is the dimension along the surface of the crown from girdle (0%) to table (100%). Rotate the hand piece as you use a burnisher to apply pressure to the beveled edge of the flange, pushing the metal over the stone. Look closely to make sure there is complete 360 degree contact against the crown.

	The amount of metal burnished over the crown should be 10 percent or more of the crown distance.
The completed bezels are ready to become a part of your fine jewelry creations. If the stones you use can take heat, the bezels can be soldered into jewelry by the traditional torch method. If they are vulnerable to heat, use a laser welder to set the bezels in place. @chapter:38 @chapter:3 @chapter:38


# Publication Year: 1990
# Title: Gemstone Enhancement and its Detection in the 1980s
# Abstract: The impact that enhancements had on the gem market in the 1980s may be unparalleled in the history of the industry. Heat treatment brought hundreds of thousands of carats of blue and fancy-color sapphires and rubies to the trade, irradiation turned literally millions of carats of white topaz into attractive blue stones, and the filling of surface-reaching separations introduced an entirely new variable to the evaluation of color and clarity in diamonds. One of the key challenges to the gemologist during this decade was the identification of these and other enhancements. This article reviews the enhancements that were introduced or played a major role during the 1980s, focusing on their detection by standard gemological techniques. @chapter:35 @chapter:1 @chapter:35


# Publication Year: 2017
# Title: Dyed Quartzite Imitation of Ruby-in-Zoisite
# Abstract: Figure 1. Green to dark green and pinkish purple to dark purple dye concentrations were observed in the fissures and structure of this quartzite, which resembled ruby-in-zoisite. Photo by HyeJin Jang-Green; field of view 9.61 mm.

The New York laboratory recently received a bracelet composed of translucent multicolored beads that closely resembled ruby-in-zoisite. Standard gemological testing of one of the round beads (measuring 8.33 × 8.17 mm) revealed an refractive index (RI) of 1.55 for both the purple and green areas (instead of approximately 1.76 or 1.69 for ruby and zoisite, respectively) and very weak red to inert fluorescence in long-wave and short-wave ultraviolet light, respectively. Microscopic observation revealed fissures and a translucent aggregated/grainy structure, both of which contained green to dark green and pinkish purple to dark purple dye concentrations (figure 1).

Although most of the translucent green and purple aggregate material we encounter for identification is ruby-in-zoisite, the gemological features of this bead were inconsistent with our expectations. Raman spectra were collected to confirm the identity. Spectra from both the purple and green areas matched quartz (figure 2). Since the material was an aggregate, we concluded that it was dyed quartzite.

Figure 2. Raman spectra collected from the sample’s purple and green areas indicated quartz rather than ruby and zoisite. Spectra are offset for clarity.
The Lab Notes section has documented many cases of dyed quartzite imitating jadeite, ruby, lapis lazuli, and sugilite (Spring 1986, pp. 49–50; Summer 1991, pp. 122–123; Summer 1995, pp. 125–126; Summer 1998, pp. 131–132; Spring 2001, pp. 62–63; and Fall 2003, pp. 219–220). But this is the first example we have seen of quartzite being used to imitate ruby-in-zoisite. This dyed quartzite provides an intriguing example for consumers to be aware of when purchasing ruby-in-zoisite. @chapter:3 @chapter:0 @chapter:3


# Publication Year: 2015
# Title: Rare Type IIb Gray-Purple Diamond
# Abstract: Figure 1. This 1.42 ct type IIb natural diamond was significant for its unusual Fancy gray-purple color and its strong emission at 776.4 nm under PL spectroscopy. Photo by Robison McMurtry.

Photoluminescence (PL) spectroscopy using several laser excitations has become the most important method for determining diamond color origin. Part of PL analysis is observing peaks that correlate with a diamond’s color, type, or other gemological properties, but for which the physical model is still unknown. One such center is the PL peak at 776.4 nm, which is commonly observed in type IIb diamonds with intensely colored (i.e., Fancy to Fancy Deep) blue to gray color and in combination with red phosphorescence (S. Eaton-Magaña and R. Lu, “Phosphorescence in type IIb diamonds,” Diamond and Related Materials, Vol. 20, No. 7, 2011, pp. 983–989). Recently, the Carlsbad laboratory tested a 1.42 ct colored diamond that showed an extremely strong 776.4 nm emission. Infrared absorption spectroscopy confirmed the specimen as a type IIb natural diamond with a boron concentration of approximately 28 ppb. This stone was notable not only for this intense emission, but also for its Fancy gray-purple color (figure 1). This is an extremely rare combination in a type IIb diamond.

Type IIb diamonds sometimes have a violet color description, but they rarely exhibit hues that are outside the blue-gray-violet range. While the perceived difference between a violet and purple diamond may be quite subtle, it is an important distinction when determining color origin. An additional reddish component that distinguishes purple from violet diamonds is extremely rare among type IIb fancy color diamonds. Other type IIb hues include gray-green or yellowish green (e.g., Summer 2009 Lab Notes, p. 136; Spring 2012 Lab Notes, pp. 47–48). Purple diamonds are quite rare and almost exclusively type Ia, their color deriving from the 550 nm band observed in their visible absorption spectra (S. V. Titkov et al., “Natural-color purple diamonds from Siberia,” Spring 2008 G&G, pp. 56–64). This absorption band is also the cause of color for many pink to red diamonds; however, the absorption spectrum for this diamond was featureless within the visible range, which is typical for type IIb diamonds. This stone is likely the first purple type IIb diamond examined at GIA.

Figure 2. With 514 nm excitation and liquid-nitrogen temperatures, the 776 nm PL peak
dwarfs the diamond Raman peak at 552.4 nm and all other PL features in the spectrum.
The intensity ratio between the 776 nm peak and the diamond Raman peak is about 42:1.
The diamond had the strongest 776.4 nm PL emission yet observed by the author (figure 2). The configuration of the optical center is unknown but might include a boron-vacancy complex (T. Ardon and S. Eaton-Magaña, “Spatial distribution of boron and PL optical centers in type IIb diamond,” 2013 GSA Annual Meeting). Red phosphorescence, centered at 660 nm, was observed using DiamondView and excited by both ultraviolet and visible-light wavelengths using fluorescence spectroscopy. The 776.4 nm PL peak is observed when the diamond is at liquid-nitrogen temperatures, but it is outside the visible range and not excited at room temperature. Therefore, this near-infrared emission, while strong, does not contribute to the color of the diamond. The diamond’s red phosphorescence, while subtle, may have been sufficient to introduce enough reddish component to render a purple color call (as opposed to the more common blue to violet). The singular occurrence of the very strong 776.4 nm PL peak and an unusual bodycolor for a type IIb diamond make this stone notable. @chapter:22 @chapter:1 @chapter:22


# Publication Year: 1987
# Title: Summer 1987 Gem News International
# Abstract: Diamonds
            Largest California Diamond Found
Colored Stones
            Brazilian Alexandrites
            Large Ekanite Found
            Chinese Marble Tiles
            “Conch Pearl” Substitute
Announcements
            Historical Jewelry from Two Collections
            Fashion Institute Symposium
            Proposed Gemstone Cut Classifcation
            Kenya Gemstone Dealers Association

To view the full section, download the PDF above. @chapter:17 @chapter:0 @chapter:17