# Publication Year: 2019
# Title: Freshwater Bead-Cultured Pearls with Multiple Features of Interest
# Abstract: Figure 1. Eleven of the 24 pearls in this necklace exhibited a shape like a dumbbell or peanut shell, which corresponded with the internal twin bead structure revealed by subsequent microradiography. Photo by Johnny Leung.

GIA’s Hong Kong laboratory recently examined a necklace consisting of 24 white baroque-shaped nacreous pearls ranging in size from 21.92 × 15.24 mm to 24.95 × 15.12 mm (figure 1). Their external appearance, high luster, and strong orient hinted at a freshwater origin. Detailed examination revealed additional features of interest.

Figure 2. A small whitish non-nacreous region was observed on one pearl under white light (left). The optical X-ray fluorescence image (right) revealed a strong green fluorescence reaction, as expected for freshwater pearls. An atypical reddish orange reaction was observed on the whitish non-nacreous portion. Photos by Sharon Tsz Huen Wu.
While their appearance was indicative of freshwater pearls, energy-dispersive X-ray fluorescence analysis was performed on a random selection to confirm their formation environment. The high manganese concentrations of 751–1728 ppm were consistent with freshwater pearls. In keeping with the reactions seen in freshwater pearls with such levels of Mn, the samples exhibited strong green fluorescence when exposed to X-rays. However, one in particular displayed moderate to strong reddish orange fluorescence on some areas of its surface (figure 2), associated with whitish non-nacreous regions on the pearl. Similar reddish fluorescence reactions had previously been observed around damaged areas of nacre on pearls examined in GIA’s New York laboratory (Summer 2013 Lab Notes, pp. 113–114). The exact reason for this reaction, which GIA gemologists have seen in cultured and natural freshwater pearls from time to time, is unknown.

Figure 3. Microradiographs revealed two round bead nuclei in one of the dumbbell-like pearls (left) and a network of tubules in the beads, resembling the parasite tubes commonly associated with saltwater shells (right). X-ray contrast permits the observation of structures near the surface and nearer the center of the pearls. Images by Sharon Tsz Huen Wu.
Eleven of these pearls had a shape resembling a dumbbell or peanut shell, indicating the possible presence of two nuclei in each. Real-time microradiography confirmed the presence of two round bead nuclei in these pearls (figure 3). The remaining 13 contained only a single round bead, consistent with the majority of bead-cultured pearls on the market. In addition, a network of tubules was observed within most of the bead nuclei. Such tubules resembled those observed in saltwater shells, which result from the burrowing actions of parasites. Thus, the bead nuclei were likely fashioned from saltwater shells rather than the usual freshwater nuclei employed. Nonetheless, it was impossible to determine the nature of the shell beads without destructive testing. Microradiography examination proved the bead nuclei were not pre-drilled, a characteristic often observed in freshwater nuclei used to culture freshwater pearls (H.A. Hänni, “Ming pearls: A new type of cultured pearl from China,” Journal of the Gemmological Association of Hong Kong, Vol. 32, 2011, pp. 23–25) and typically encountered by GIA during testing. While pearls cultured with two bead nuclei are relatively uncommon, their existence has been acknowledged in the literature (Fall 1993 Lab Notes, pp. 202–203). The twin bead structure clearly influenced the appearance of these pearls and resulted in some pleasing baroque shapes.

Figure 4. Artificial material was observed filling and masking surface blemishes on some of the pearls in the necklace. Fields of view 5.68 mm (left) and 3.74 mm (right). Photos by Sharon Tsz Huen Wu.
Finally, upon closer examination, a “glittery” grainy material was observed on the pits and blemishes of several pearls (figure 4). This resembled the essence d’orient applied on the surface of some imitation pearls. Raman analysis of this material yielded a number of peaks (e.g., 634–639 cm–1 and 1604 cm–1) that matched, to some degree, the peaks of the filling material described in an earlier reference (Winter 2017 GNI, pp. 482–484).
While the GIA laboratory examines pearl strands on a daily basis, we seldom encounter one submission possessing several interesting features such as the twin bead structure, reddish orange optical X-ray fluorescence, and filled surface blemishes. It is important for gemologists to always stay alert to the surprises they might find when examining pearls. @chapter:11 @chapter:4 @chapter:11


# Publication Year: 2015
# Title: Fluorite Sphere with Phosphorescent Coating
# Abstract: Figure 1. This large fluorite sphere proved to be coated with a fine grained phosphorescent powder and a colorless plastic. Photos by Don Mengason.

              A large green 2,685 ct, 120 mm sphere was recently examined in the Carlsbad lab. The sphere displayed an unusual phosphorescent reaction when exposed to a strong illumination source (figure 1). These phosphorescent stones are commonly referred to by the misnomer “night glowing pearl.”

The sphere was warm to the touch. Microscopic examination revealed a colorless plastic coating, readily identifiable by the numerous trapped gas bubbles trapped within (figure 2, top). Upon further inspection, a subsurface granular material that contributed both a very subtle green component to the overall bodycolor of the sphere was also observed (figure 2, bottom). The granular material was also responsible for the material’s phosphorescence. It was apparent from these observations that the colorless coating was used to adhere the fine-grained powder to the surface of the sphere. The coating acted as an enhancement, contributing a near-vitreous luster to the finished sphere. The stone also contained numerous cleavage cracks oriented in numerous unrelated directions, and fractures along grain boundaries indicative of a crystalline aggregate material. Because the fine-grained powder was coated with polymer, we were unable to analyze it for identification; however, the appearance is consistent with that of a strontium aluminate material that has been previously reported to coat “night glowing pearls” (Spring 2005 Lab Notes, pp. 46–47).

	Figure 2. Gas bubbles were trapped in the colorless plastic coating of this “night glowing pearl” (top) and a granular material underneath the colorless coating was the source of the phosphorescence (bottom). Photomicrographs by Nathan Renfro; field of view 3.55 mm.
Due to the plastic coating, a refractive index measurement of the substrate material was not possible. Raman spectroscopy positively identified the substrate material as fluorite, which was consistent with the microscopic appearance.

While night glowing pearls have been previously reported, this example was particularly unique because of its large size and the fact that the phosphorescent reaction was easily induced by visible light. It was also unusual that the phosphorescent material was nearly invisible to the naked eye, creating the appearance of a normal, uncoated fluorite sphere. @chapter:26 @chapter:0 @chapter:26


# Publication Year: 2008
# Title: Natural-Color Purple Diamonds from Siberia
# Abstract: Twelve natural-color purple diamond crystals from Siberia, and seven round brilliants that were faceted from some of these crystals, were studied using spectroscopic methods to better understand their color and its causes. Aspects of their color and the various structural defects in these purple diamonds are due to their post-growth plastic deformation in the earth. All the samples exhibited prominent parallel planar lamellae along which the purple color was concentrated. @chapter:29 @chapter:1 @chapter:29


# Publication Year: -
# Title: Moonstone History and Lore
# Abstract: Moonstone’s mysterious, billowy, glow has fascinated people for centuries.

                      According to Hindu mythology, moonstone is made of solidified moonbeams. Many other cultures also associate this gem with moonlight, and it’s easy to see why. Its internal structure scatters the light that strikes it, creating a phenomenon known as adularescence. The visual effect is reminiscent of the full moon shining through a veil of thin, high clouds.

	Moonstone has long been associated with the moon. - © GIA & Tino Hammid, courtesy 23rd St. Shop, Santa Monica
Legends say that moonstone brings good luck. Many believed that you could see the future if you held a moonstone in your mouth during a full moon.

Adularescent moonstone was once called “adularia.” The name originated with a city in Switzerland, Mt. Adular (now St. Gotthard), that was one of the first sources of fine-quality moonstone.

Great designers of the romantic Art Nouveau era, such as René Lalique and Louis Comfort Tiffany, featured the pale gem in custom jewelry. Moonstone was also a favorite among artisans of the Arts and Crafts era in the last half of the nineteenth century, who used it in handcrafted silver items.

During the 1960s “flower child” movement, moonstone provided its wearers with the desired ethereal look, and designers of the 1990s New Age movement again turned to moonstone’s natural beauty for inspiration. @chapter:31 @chapter:2 @chapter:31


# Publication Year: 1981
# Title: A Cubic Zirconia Refractometer
# Abstract: With the development by C. D. West of practical high refractive-index liquids, the major barrier to extending the range and durability of the refractometer has been the need for an isotropic substance with an index of refraction higher than that of the glass commonly used. On the basis of the author's experiments with a cubic zirconia refractometer, CZ - with its relatively low cost, high refractive index and hardness - shows great promise for meeting this need. @chapter:19 @chapter:1 @chapter:19


# Publication Year: 2008
# Title: Coloring of Topaz by Coating and Diffusion Processes: An X-Ray Photoemission Study of What Happens Beneath the Surface
# Abstract: Surface-treated topaz has become a viable alternative to topaz colored by irradiation.
Unlike irradiation, which modifies the entire gemstone, coloration by chemical modification is limited to the near-surface region. The treatment techniques are well established, but less is known about how the processes involved create the desired appearance. In this study, X-ray photoemission spectroscopy in combination with sputter depth profiling proved successful in characterizing two fundamentally different coloration mechanisms of chemically treated topaz: colored coatings and diffusion-induced coloration. @chapter:16 @chapter:0 @chapter:16


# Publication Year: 2024
# Title: Gold and gold jewelry are hot in the Chinese market.
# Abstract: A gold and jewelry store in Shanghai was interviewed, stating that during the recent Chinese New Year period, gold sales were very strong. They sold up to 1,000 gold bars in a single day, and one customer bought jewelry worth over 200,000 yuan in one go. Despite the high gold prices, reaching up to 625 yuan/gram, consumers were ready to purchase these products. Of particular interest is the growing trend of young consumers becoming significant buyers, whether for personal adornment or investment purposes.

According to trends in the jewelry industry in 2023, the majority of gold buyers are women aged 18 to 34 from both primary and secondary cities. The new generation of consumers is growing rapidly, with those born after 2000 appreciating the value-retaining and appreciating qualities of gold, leading to a keen interest in gold jewelry consumption.

In reality, Chinese people have a long-standing preference for gold consumption, and this trend is expanding across all age groups. Due to the stable gold prices over the past two years, gold consumption has become even more popular. On January 25, 2024, the Chinese Gold Association revealed data showing an 8.78% increase in gold consumption in 2023 compared to the previous year. Looking at consumption types, gold jewelry consumption increased by 7.97%, while gold bar and coin consumption increased by 15.70% compared to the same period the year before.

Comparing to previous gold consumers, aside from buying gold bars and gold jewelry, today's youth are also falling in love with "gold beans" weighing 1 gram because their prices are not excessively high. Moreover, on social media, people compete to share their experiences in hoarding "gold beans." There's a saying that goes, "If you save one bean per month, you'll have 12 grams per year," or some say, "If you save 500 beans, you can exchange them for a car." For those who see it as a long-term investment, they believe that this method is more fun and reliable than depositing money in banks.

Since ancient times, gold has been a symbol of wealth and power. Nowadays, gold has successfully captivated the attention of young people once again. Whether it's gold ingots or tiny gold beans purchased for New Year celebrations and birthdays, or large pieces of gold jewelry bought for various occasions like weddings and gift-giving, the Chinese have shown their money-saving ideas by saying, "Reserving gold no matter where you are and when" is another way of ensuring financial stability.

These young people don't blindly follow trends but rather prioritize wealth accumulation through possession. The consumer mindset of young people has become more reasoned. "Investing in gold" is seen as investing in oneself. Hence, gold has become a consumer product that holds much more value than designer handbags.
In recent years, self-confidence and a fondness for traditional culture have become a trend among the younger generation. From dressing in Hanfu (traditional Chinese clothing) to reviving traditional music, young people are gradually discovering the charm and beauty of ancient culture. In this context, gold seals, which have been a long-standing jewelry item among the Chinese, have also gained popularity. With ancient gold techniques that emphasize traditional gold casting, these items are considered cultural heritage treasures that cannot be replaced. They have become increasingly popular due to their exquisite craftsmanship, including traditional techniques like carving, weaving, engraving, and embedding ancient gold patterns. Despite their relatively high prices, many young people still appreciate them.

To meet market demands, some gold brands have collaborated with museums to launch limited edition co-branded models. Cultural artifacts from museums have become an inspiration for designing gold jewelry collections, incorporating patterns like the Ruyi motif, bird motifs, and diamond-inlaid patterns on gold. This has made gold not only beautiful in style but also rich in cultural significance, truly admired by young people for its genuine Chinese luxury.
The comment from Mr. N at Nanning City suggests that gold and jewelry are becoming highly popular products in the Chinese market. They observe that the younger consumer group in both the main and secondary cities of China has become significant in purchasing gold and jewelry. These products have shifted from being outdated to becoming coveted items in the market, aligning with the increasingly rational consumption behavior among Chinese people.

Additionally, ancient gold, which combines traditional craftsmanship with modern trends, is a result of Chinese culture and is a significant Soft Power element. Thailand is renowned in the gem and jewelry sector for its beautiful designs, exquisite craftsmanship, and unique styles. This could be another option for Chinese consumers when choosing to purchase jewelry and gemstones.

Therefore, Thai entrepreneurs interested in the Chinese market should closely monitor market trends and study the behavior of Chinese consumers to effectively meet market demands. @chapter:32 @chapter:3 @chapter:32


# Publication Year: 2007
# Title: Trapiche Tourmaline from Zambia
# Abstract: Well-formed crystals of green tourmaline from northwestern Zambia show a growth pattern reminiscent of trapiche emerald/ruby when sliced perpendicular to the c-axis. In fact, such slices were originally encountered in parcels sold as emerald in Zambia. The trapiche appearance most likely originates from skeletal growth, with the pattern formed by a black carbonaceous substance (mostly graphite) that partially filled growth tubes concentrated in three areas: (1) along the three edges of the trigonal pyramids r {101–1} or r’ {011–1 – }, (2) at the interface between the trigonal pyramids and the prism a {112–0}, and (3) between individual growth sectors of the prism a. Spectroscopic and chemical analyses indicate that the tourmaline is uvite that is colored green by a vanadium-related mechanism. To the authors’ knowledge, this is the first occurrence of trapiche tourmaline. @chapter:12 @chapter:0 @chapter:12


# Publication Year: 2021
# Title: Spectroscopic Characteristics of Low-Temperature Heated Blue to Violet Spinel
# Abstract: Figure 1. Color-calibrated photos of blue to violet spinels before heating (left) and after heating at 1000°C for four hours (right). There are three groups of spinel samples in this study: violet (top row), iron-dominated blue (middle row), and cobalt-dominated blue (bottom row). Photos by Sasithorn Engniwat.
Although spinel is rarely treated, there have been some heated spinels available in the trade. The effect of heat treatment on pink to red spinel has been previously reported (e.g., S. Saeseaw et al., “Distinguishing heated spinels from unheated natural spinels and from synthetic spinels,” 2009, GIA Research News, https://www.gia.edu/gia-news-research-NR32209A; A. Peretti et al., “Heat-treatment of spinel,” in World of Magnificent Spinels: Provenance and Identification, GRS Gemresearch Swisslab, 2015, pp. 269–278). Chromium-bearing spinel with pink to red color generally becomes darker after heat treatment, and the clarity of spinel containing particulate clouds can be significantly enhanced by heating between approximately 950° and 1150°C (S. Saeseaw et al., 2009).
In addition to the most popular pink to red spinel, another important and desirable variety is blue spinel, especially with a vibrant cobalt blue color. The dominant chromophores in blue to violet spinel includes Fe2+ and Fe3+ at both tetrahedrally (T) and octahedrally (M) coordinated sites of spinel structure as well as Co2+ at the T site (G.B. Andreozzi et al., “Color mechanism in spinel: A multi-analytical investigation of natural crystals with a wide range of coloration,” Physics and Chemistry of Minerals, Vol. 46, 2019, pp. 343–360; V. D’Ippolito et al., “Color mechanism in spinel: Cobalt and iron interplay for the blue color,” Physics and Chemistry of Minerals, Vol. 42, 2015, pp. 431–439). Previous works have revealed the application of cobalt diffusion treatment to enhance blue color in spinel (e.g., S. Saeseaw et al. “GIA lab reports on a new cobalt diffusion treatment of natural spinel,” GIA Research News, 2015, https://www.gia.edu/gia-news-research/cobalt-diffusion-natural-spinel-report). A study on the heat treatment of blue spinel without external chemical diffusion is lacking in the literature, to our knowledge.
To understand the change of chromophores in blue to violet spinel caused by heat treatment, this preliminary study involved exploratory heat treatment of samples from various localities: Madagascar, Myanmar, Tanzania, and Vietnam. The samples were separated into three groups: violet, iron-dominated blue, and cobalt-dominated blue spinel (figure 1, left).

Figure 2. Representative UV-Vis-NIR spectra of unheated spinels for the three color groups. They have relatively similar absorption spectra with different intensities and some band positions, depending on Fe and Co contents. A series of Fe absorption bands in the spectrum consists of Fe2+ at T site (TFe2+) bands at approximately 371, 385, 400, 558, 580, and 780 nm; Fe2+ at M site (MFe2+) band at around 920 nm; Fe3+ at M site (MFe3+) band at 457 nm; MFe2+- MFe3+ intervalence charge transfer (IVCT) band at about 655 nm; and Co2+ at T site (TCo2+) bands at approximately 558, 580, and 625 nm (Andreozzi et al., 2019; D’Ippolito et al., 2015). Fe and Co concentrations reported in the figure were analyzed by LA-ICP-MS.
UV-Vis-NIR spectrum of representatives in each group show relatively similar absorption spectra (figure 2), consisting of a strong UV-edge absorption at approximately below 330 nm; multiple absorption bands between 350 and 1100 nm of Fe2+, Fe3+ at T and M sites; and multiple bands between 500 and 670 nm of Co2+ at the T site (Andreozzi et al., 2019; D’Ippolito et al., 2015). With a very similar absorption pattern between violet and blue iron-dominated spinels, the difference in color appearance is associated with different intensity of absorption bands which is more intense in iron-dominated blue spinel due to higher Fe concentrations (Andreozzi et al., 2019). The spinel samples were heated at 600°, 700°, 800°, 900°, and 1000°C in air and held for four hours at each heating temperature. Progressively heating from 600° to 1000°C showed that violet color changed little in this temperature range, whereas blue spinel became more grayish after heating at approximately 800°–900°C (figure 1, right). Heat treatment could affect the color appearance of iron-dominated blue spinel colored much more than cobalt-dominated blue spinel.

Figure 3. UV-Vis-NIR spectra comparisons of cobalt blue (top), blue and violet spinels (bottom) in figure 2, before heating (solid line) and after heating at 1000°C for four hours (dashed line). Broader absorption bands, with less prominent bands below 650 nm and more prominent bands at around 920 nm, were observed.
After heat treatment (figure 3), the spectra displayed generally broader absorption bands, with less prominent bands below 650 nm and more prominent bands at around 920 nm. The broadening of the chromium emission peak in photoluminescence spectroscopy (PL) is an effective criterion for detecting heat treatment in spinel (e.g., Saeseaw et al., 2009; Peretti et al., 2015). PL spectra of the treated samples in this study were also analyzed and showed that the Cr emission peak of the material broadened after heating at 800°–900°C. The change in color and spectroscopic data after heat treatment resulted from a direct spinel transforming to a partially inverse spinel (R. Widmer et al., “Effects of heat treatment on red gemstone spinel: Single-crystal X-ray, Raman, and photoluminescence study,” Physics and Chemistry of Minerals, Vol. 42, 2015, pp. 251–260) as well as the changes of valence and site distribution of Fe chromophores in the spinel structure. The less desirable blue color of the treated spinel in this preliminary study, regardless of any improvement in clarity, suggests that the heat treatment of the blue to violet spinels was likely unintentional. In addition, as demand for gray colored spinels has increased in the trade over the past few years (Spring 2019 GNI, p.130), some concerns about heat treatment in gray spinels should be raised. @chapter:24 @chapter:0 @chapter:24


# Publication Year: -
# Title: 2018: A Good Year for Finding Mega-Diamonds
# Abstract: The 472 ct diamond from Lucara Diamond’s Kerowe mine is the largest found at the mine this year, which has, thus far, yielded five diamonds over 100 carats. Photo courtesy of Lucara Diamond Corp.

It’s turning out to be a good year for very large diamonds.

The three diamond mining companies that specialize in digging up large stones have found some really big ones during the first quarter of the year, ending a relative drought.

Gem Diamonds unearthed five diamonds over 100 carats in January after finding “only” eight such stones in all of 2017. One of those five was the 910 carat (ct) Letseng Legend (named after the company’s mine in Lesotho), which it recently sold for $40 million at a special auction. Then, in March, the same company recovered a 152 ct diamond.

Lucara Diamond Corp., which operates the Kerowe mine in Botswana, found five 100 ct-plus diamonds during the first quarter. And in April, the company announced it had discovered a 472 ct diamond in the same section of the mine where it discovered the 1,100 ct Lesedi la Rona diamond two years earlier. The 472 ct is the third largest diamond to come from the mine. Lucara executives described the color as “top light brown,” which means it is likely to polish out as an M-to-O color stone.

Shortly after this discovery, Lucara mined three more 100 ct-plus diamonds, including a 327 ct rough it described as a “high-color” stone, referring to D-E-F color grades on the GIA scale. The company will sell both diamonds at a special tender auction in June.

Kerowe’s output declined 27% last year due to production problems that forced the company to shift operations away from the richest area of the mine where most of the very large diamonds have been found.

Angola’s Luo Mine yielded a 46 ct fancy pink rough in April, reported Lucapa Diamond Company, the Australia-based operator of the mine. Luo, one of the smaller mines (producing fewer than one million carats yearly) specializing in major diamonds, has produced stones as large as 404 carats. The 46 ct diamond is the largest fancy color diamond it has produced since it came onstream four years ago.

The mysterious 6.16 Fancy Dark gray-blue Farnese Blue diamond was kept in a small wooden box away from the public eye for more than two centuries. The French script on the silver plaque on the box reads: “Remarkable blue brilliant. This historical stone was offered by the Philippine Islands to Elisabeth Farnese, Queen of Spain, wife of Philippe V, great-grandfather of the Comte of Villafranca, current owner of that stone.” Photo courtesy of Sotheby's.
AUCTIONS
The royal-provenance 6.16 ct pear shape Farnese Diamond drew a top bid of $6.7 million at Sotheby’s May 15 auction in Geneva, a price well above its high estimate of $5 million. The diamond, graded Fancy Dark grayish-blue by GIA, was a gift from King Phillippe V of Spain to his bride Elisabeth Farnese after they married in 1714. After her death, the diamond passed through royal houses in Italy and Austria, most of the time hidden in a small wooden box.

At the same auction, a GIA-graded 51.71 ct D Fl Type IIa diamond sold for $9.24 million; a 14.01 ct Kashmir sapphire sold for $1.8 million; and a 9.7 ct Fancy Light purple pink diamond soared far beyond its high estimate of $672,000 to sell for nearly $2.6 million.
LAS VEGAS
The industry is anticipating respectable demand for diamonds and colored gemstones at the upcoming JCK Show in Las Vegas. Retail demand is steady in the U.S. and climbing again in China.

In the U.S., the Conference Board Consumer Confidence Index rose in April.

“Consumers’ assessment of current conditions improved somewhat, with consumers rating both business and labor market conditions quite favorably,” said Lynn Franco, director of economic indicators at the Conference Board. “Consumers’ short-term expectations also improved, with the percent of consumers expecting their incomes to decline over the coming months reaching its lowest level since December 2000 (6%). Overall, confidence levels remain strong and suggest that the economy will continue expanding at a solid pace in the months ahead.”

In China, first quarter jewelry and watch sales climbed 8% on the mainland and 22% in Hong Kong, the China and Hong Kong statistics bureaus reported. Sales at the end of the quarter were particularly strong in both regions. @chapter:50 @chapter:3 @chapter:50


# Publication Year: 1990
# Title: An Investigation of a Suite of Black Diamond Jewelry
# Abstract: This article reports on the gemological properties of six large black diamonds set in a suite of jewelry. The color of the diamonds was determined to be caused by numerous black inclusions lining cleavages and fractures. Such stones are difficult to cut and polish, and require great care in setting. They can be separated from artificially irradiated dark green black-appearing diamonds and from other black and black-appearing materials on the basis of their distinctive visual and gemological features. @chapter:44 @chapter:1 @chapter:44


# Publication Year: 1989
# Title: Zircon from the Harts Range, Northern Territory, Australia
# Abstract: Gem-quality zircon from a relatively underdeveloped locality in the Harts Range of central Australia is described. While exhibiting many properties of other gem zircons, this material is unusual in its almost total lack of radioactive trace elements. Thus, there is little or no radiation-related structural damage as is the case with some other gem zircons. The Harts Range material occurs in a size, quality, and color range suitable for faceting. @chapter:18 @chapter:0 @chapter:18


# Publication Year: 2013
# Title: Imitation Larimar
# Abstract: Pectolite is a mineral of the wollastonite group with the chemical formula NaCa2Si3O8(OH). It has a refractive index of 1.599–1.628, with a typical spot RI reading of about 1.60, and a specific gravity of 2.81. The light blue variety of this mineral, known by the trade name Larimar, has only been found in the Dominican Republic (R.E. Woodruff and E. Fritsch, “Blue pectolite from the Dominican Republic,” Winter 1989 G&G, pp. 216–225; see figure 1).

	Figure 1. This 3.91 ct ceramic imitation of Larimar (left) is shown with Larimar from the Dominican Republic. Photo by Lore Kiefert.
One of these contributors (PG) recently acquired a 3.91 ct drop-shaped cabochon, purchased in India as a Larimar imitation, that consisted of a ceramic material (figure 1, left). According to the vendor, the material was manufactured in China. Close microscopic examination showed white gas bubbles and blue color concentration (figure 2).

	Figure 2. Microscopic observation reveals dark blue color concentrations and whitish gas bubbles. Photomicrograph by Lore Kiefert; magnified 40x.
The cabochon’s spot RI reading of 1.53 and SG of 1.87 were distinctly lower than the values for Larimar. Semi-quantitative EDXRF chemical analysis gave a composition of 95% Al2O3 and 4% SiO2, with traces of SO3, K2O, CaO, Sc2O3, Cr2O3, Fe2O3, and Ga2O3. In contrast, the average composition of pectolite consists of 54.23% SiO2, 33.74% CaO, 9.32% Na2O, and 2.71% H2O.

Although the imitation material does indeed resemble Larimar, standard gemological tests such as microscopy, refractive index, and specific gravity should be sufficient to distinguish it.

Lore Kiefert
Gubelin Gem Lab Ltd.
Lucerne, Switzerland

Peter Groenenboom
AEL Arnhem
Arnhem, Netherlands @chapter:15 @chapter:0 @chapter:15


# Publication Year: 2012
# Title: Precision Measurement of Inter-Facet Angles on Faceted Gems Using a Goniometer
# Abstract: A classic two-circle reflecting goniometer was used to measure inter-facet angles on five faceted diamonds that included round brilliants and fancy shapes. The instrument provided significantly better precision (to within 2 minutes, or 0.034°) than the non-contact optical scanner that is customarily used at GIA for this purpose. With some procedural modifications, the goniometer could make measurements of all inter-facet angles, including the pavilion facets. The technique is potentially valuable for producing a well characterized set of reference stones for calibrating non-contact optical scanners. @chapter:44 @chapter:1 @chapter:44


# Publication Year: -
# Title: Kunzite Care and Cleaning
# Abstract: With proper care, kunzite jewelry will provide a lifetime of beautiful adornment. - Courtesy Loretta Castoro Signature Collection

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

	Kunzite rates 6.5 to 7 on the Mohs hardness scale.
Because it has perfect cleavage in two directions, kunzite requires special care during cutting, polishing, and mounting. It’s not very tough, so a hard blow might split it, and extreme pressure or sharp temperature changes might cause it to break. To reduce the risk of breakage, jewelers prefer to set valuable kunzite gems in protective mountings or use them in pieces that aren’t exposed to too much wear, like pendants and pins.

Kunzite rates 6.5 to 7 on the Mohs hardness scale. Its toughness rating is poor due to its cleavage.

Stability
High heat or sudden temperature changes can cause breaks in kunzite. The gem’s color can fade with prolonged exposure to heat or intense light.

Cleaning
It’s important to avoid steam or ultrasound for cleaning kunzite: Warm, soapy water works best.

	A safe way to clean kunzite jewelry is to use lukewarm water with mild soap and a toothbrush. - Eric Welch
Treatment and Durability Considerations
Kunzite might be irradiated and then heated to enhance its color. The color of irradiated, heated kunzite can fade with exposure to heat and light, just as it does in naturally colored kunzite.

Besides protecting it from heat and light, kunzite should be protected as much as possible from sharp blows that can cause breakage along cleavage planes. @chapter:16 @chapter:0 @chapter:16


# Publication Year: 1981
# Title: Cryogenics, an Aid to Gemstone Testing
# Abstract: Cooling of gemstones to low temperatures provides for enhanced detail in the absorption spectra. This article identifies some simple techniques for cooling gems that are available to the jeweler-gemologist and offers a detailed description of the procedures used in the research laboratory for automatic recording of spectra at low temperatures. Examples of the differences observed between spectra recorded on stones held at room temperature and those recorded for the same stones at significantly lower temperatures are presented for diamond, emerald, and synthetic alexandrite. @chapter:39 @chapter:1 @chapter:39


# Publication Year: 2001
# Title: Spring 2001 Gem News International
# Abstract: Diamonds
            White House Conference on “Conflict” Diamonds
TUCSON 2001
Diamonds
            Update on GIA’s Diamond Cut Research
Colored Stones and Organic Materials
            Cultured Abalone Pearls from California
            Benitoite Mine Sold
            Emeralds from Laghman, Afghanistan
            First Production of Emeralds from Piteiras, Brazil
            Educational Iolite
            “Hte Long Sein” Jadeite
            Kunzite from Nigeria
            “Rainbow” Obsidian from Jalisco, Mexico
            New Production of Indonesian Opal
            Australian Prehnite Returns
            “Yosemite” Topaz
            Colored Tourmaline from Northern Pakistan
            Fashioning the “Green King of Africa” Tsavorite
            Highlights from the TGMS Show and Mineralogical Symposium
            Faceted Vesuvianite from California
Synthetics and Simulants
            Opal Imitations
            Green Flame-Fusion Synthetic Sapphire
Treatments
            Platinum Coating of Drusy Materials
Miscellaneous
            An Attractive Way to Display Loose Gemstones
            Micromosaics from Natural Gemstones
Announcements
            Leigha Theft
            Conferences
            Exhibits
                        Gold of Africa Museum
                        Romancing the Stone: The Many Facets of Tourmaline
                        Programa Royal Collections

To view the full section, download the PDF above. @chapter:4 @chapter:0 @chapter:4


# Publication Year: 1983
# Title: Fall 1993 G&G Lab Notes
# Abstract: Clarified Amber Beads
Brown-Pink Diamond with "Green Graining"
Light Violet-Gray Diamond
Strain Phantom in Diamond
Synthetic Yellow Diamond Crystal
Treated Green Diamond with a Blue Color Zone
Devitrified Glass, Resembling Actinolite
Bleached/Polymerized Jadeite Update
Unusual "Twin" Cultured Pearl
Eroded Cultured Pearls
Color-Zoned Pink Quartz
Synthetic Ruby: Another lmitation Ruby "Crystal"
Ruby in "Invisible" Mountings
Ruby as the Top Stone in an Asteriated Doublet

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


# Publication Year: 2023
# Title: Trends in the Jewelry and Gemstone Market in Germany for 2023.
# Abstract: As the situation of the COVID-19 pandemic in Germany begins to ease, the jewelry industry is showing signs of recovery since 2024. It is notable that the fine jewelry sector, comprising high-value items, demonstrates a greater potential for sales compared to costume jewelry. Besides being decorative, mineral jewelry such as gold, platinum, and silver remains desirable among consumers. Germans believe that during uncertain times, minerals can retain market value better than other jewelry types and may even appreciate in the long term.
Trends in the consumption of jewelry and gemstones in the German market:
1) Increasing Digitization of the Jewelry Industry:
   Jewelry retail has long been crucial, but many physical stores closed during the COVID-19 crisis, providing an opportunity for online retailers to play a more significant role and grow. Currently, popular online fashion platforms in Germany include Amazon, Zalando, and aboutyou. Specific online stores for jewelry like Kraemer, Valmano, and Schmuckladen are gaining traction. Some companies are using AR technology for virtual try-ons, and programs to help customers find suitable diamonds or gemstones based on their preferences and budgets. However, online sales for high-end or expensive jewelry are not yet highly popular.
2) Consumer Emphasis on Sustainability:
   Sustainable considerations have become increasingly important for jewelry consumers. They avoid products not certified as sustainable or "fair trade," fearing unethical sourcing practices. Newer consumers are also interested in lab-grown diamonds or synthetic pearls for their affordability and sustainability. Materials like recycled wood and cork are gaining popularity in fashion jewelry production, as seen with brands like Korkallee and Holzkern, particularly among smaller customer segments.
3) Jewelry Trends for 2024:
   - Simple, classic jewelry with emphasis on high-quality materials.
   - Thick-link chain jewelry such as rings, necklaces, and bracelets made from gold or silver.
   - Straight-line graphic style jewelry with clean and simple designs.
   - Minimalist style jewelry with layered sizes such as rings, necklaces, and earrings.
4) Popular Jewelry Materials for 2024:
   - Gold continues to be popular for its luxurious and classic appeal, including white, rose, and yellow gold.
   - Silver remains a popular metal for creating classic and fashionable rings, necklaces, bracelets, and earrings.
   - Pearl jewelry is making a comeback, offering unique beauty and natural charm in various shapes like drops or baroque styles.
Franz Fischer's Comments:
Currently, Germans prioritize quality and affordability when purchasing jewelry and gemstones. Sustainability is also a significant factor. Showcasing transparent production lines and sustainable practices can enhance brand image and attract importers looking for quality jewelry and components, especially gold, silver, and popular colored gems. Thailand remains a crucial source for jewelry and components, appreciated for its craftsmanship, design diversity, and growing pool of new entrepreneurs and designers. Thus, it's an intriguing prospect for international importers seeking distinctive and trend-following design work. @chapter:32 @chapter:3 @chapter:32


# Publication Year: 2017
# Title: Quarterly Crystal: Molybdenite Phantoms in Quartz
# Abstract: Figure 1. Weighing 378.73 (left) and 294.05 ct (right), these two quartz crystals contain phantoms composed of an abundance of dark silvery gray to black hexagonal inclusions. Photo by Kevin Schumacher.

Quartz is the most abundant mineral found in the earth’s crust. When it forms as solid single crystals, it can serve as a transparent and durable host for a wide variety of mineral inclusions. The two crystals seen in figure 1 came from collector Terry Szenics (Massapequa, New York), who found them in 2004 as part of a very small discovery at the Confianza mine in the Coquimbo region of Chile.

At a glance, the inclusions in the two crystals looked as though they might be hematite, a common iron oxide. However, laser Raman microspectrometry identified them as molybdenite (figure 2), a hexagonal molybdenum sulfide and a much more unusual inclusion than hematite. The inclusions were situated in the quartz crystals in the form of phantoms that developed through the deposition of the molybdenite on the surface of the quartz. The host then continued to grow, enveloping the molybdenite as inclusion planes tracing the form of the original quartz host.

Figure 2. The hexagonal crystals in this phantom plane in quartz were identified through Raman analysis as molybdenite. Photomicrograph by Nathan Renfro; field of view 7.19 mm. @chapter:15 @chapter:0 @chapter:15


# Publication Year: 2019
# Title: Blue Gahnite from Nigeria
# Abstract: Figure 1. Three single octahedra of natural gahnite, approximately 1.5 ct each, from Kaduna State, Nigeria. Photo by Robison McMurtry.

In recent years, Nigeria has gained considerable attention in the gem trade for the discovery of sapphires reportedly from the Mambilla Plateau in Taraba State. In addition to sapphires, spinels have been sporadically mined in Jemaa and recently in Kagoro, both in Kaduna State (figure 1). The spinel group of minerals, with a general chemical formula AB2O4, has a total of 22 different species. Four of these species have Al predominantly occupying the octahedral site: spinel (MgAl2O4), galaxite (MnAl2O4), hercynite (FeAl2O4), and gahnite (ZnAl2O4). The spinels from Kagoro have been identified as gahnite, the zinc end member. Gahnite is one of the rarer members of the spinel group of minerals, typically found at zinc deposits. Most crystals are very small, included, and translucent to opaque. Faceted gems are very collectible due to their rarity and color.
The geology of the Nigerian spinels has been previously studied (R. Jacobson and J.S. Webb, “The pegmatites of central Nigeria,” Geological Survey of Nigeria Bulletin, No. 17, 1946, pp. 1–61), and the deposits can be subdivided into three groups based on their mineralogy: (1) microcline-quartz pegmatites, which commonly occur within the calc-alkaline granitoids and are rarely mineralized; (2) microcline-quartz-mica pegmatites, found within metasedimentary sequences; and (3) quartz-mica veins, which occur in schists and gneisses or marginal to group 2 pegmatites. Gahnite occurs in groups 2 and 3. Knowledge of the composition of zinc-rich spinels is useful in separating a wide variety of source environments. For example, Zn content is high in spinels occurring in rocks that have experienced low-grade metamorphism and high oxygen and sulfur fugacity (fO2 and fS2), whereas Zn content is lowest in high-grade metamorphic rocks (A. Heimann et al., “Zincian spinel associated with metamorphosed Proterozoic base-metal sulfide occurrences, Colorado: A re-evaluation of gahnite composition as a guide in exploration,” Canadian Mineralogist, Vol. 43, No. 2, 2005, pp. 601–622).
Standard gemological examination of three rough octahedra (figure 1) gave the following properties: color—blue; pleochroism—none; refractive index—1.791 to over the limit (flat reading from polished crystal face); hydrostatic specific gravity—4.180–4.294; fluorescence reaction—inert to both long- and short-wave UV; and color filter reaction—red. Internal characteristics observed with a gemological microscope were colorless unidentified crystals, fingerprints, and a red-brown crystal inclusion identified by Raman spectroscopy as sphalerite (figure 2).

Figure 2. Raman identification of this inclusion was consistent with sphalerite. Photomicrograph by Nathan Renfro; field of view 0.91 mm.

Figure 3. The visible spectrum of the Nigerian gahnite from Kagoro. The absorption bands from ~500 to 650 nm are largely due to Co2+, but with modification from iron absorption bands. Absorption bands around 462 and 470 nm are related to iron chromophores.
Advanced spectroscopic testing was performed on the three samples. The Raman spectra were typical of gahnite, with peaks at 420, 510, and 661 nm. The visible spectrum showed significant cobalt absorption bands (figure 3) between 500 and 620 nm, with additional contribution from iron absorption bands modifying the cobalt absorption spectrum (e.g., A.C. Palke and Z. Sun, “What is cobalt spinel? Unraveling the causes of color in blue spinels,” Fall 2018 G&G, pp. 262–263).
Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) analysis was used to obtain the accurate chemistry of the three stones. The chemical composition was acquired by a ThermoFisher iCAP Q ICP-MS coupled with an Elemental Scientific Laser NWR213 laser ablation system. NIST 610 and 612 were used as external standards, and 27Al was used as an internal standard. LA-ICP-MS results (see appendix 1) showed that the three stones were predominantly composed of more than 90 mol.% gahnite (ZnAl2O4), with minor other end members of Al-spinel species. They should thus be classified as gahnites.

Figure 4. A vertical line 1 and a horizontal line 2, containing a total of 44 spots, were selected to apply LA-ICP-MS analyses across the whole section. Mol.% end member vs. position profiles revealed that the stone was predominantly composed of gahnite with minor hercynite, spinel, and galaxite. Detailed information on major element chemistry, site distribution, and species for each spot can be found in appendix 1. Spot spacing is 200 microns.

Figure 5. Trace element vs. position profiles revealed that the outer rims had higher concentrations of V and Co, but lower concentration of Ni than the inner rims and core. Detailed information on trace elements for each spot in lines 1 and 2 can be found in appendix 2.
To better understand the composition of this type of spinel, we prepared a cross-section cut from the middle of one octahedral crystal, sample NBS3 (figure 4). A vertical line of 22 spots (figure 4, line 1) and a horizontal line of 22 spots (figure 4, line 2) were selected to cross the whole section from outer rims to the opposite outer rims for LA-ICP-MS analyses. All the spots showed more than 90 mol.% gahnite with hercynite as the second most abundant species (figure 5). Spots near the outer rims contained more hercynite than spots on the inner rims and core. The mol.% end member distribution was very consistent throughout the whole section. Nine trace elements for each spot in lines 1 and 2 were plotted in figure 5. In general, the outer rims had higher concentrations of V and Co but lower concentration of Ni than the inner rims and core. @chapter:6 @chapter:0 @chapter:6


# Publication Year: 1995
# Title: Gem-Quality Grossular-Andradite: A New Garnet from Mali
# Abstract: A find of new gem garnets has been made in contact metamorphic deposits in the Republic of Mali, western Africa. These garnets, primarily yellow-green to brown but also (rarely) intense green, have compositions between grossular and andradite. Although garnets of similar composition are relatively well known, this is the first documented occurrence of gem-quality material in commercial quantities. Because this gem variety is not represented by any of the gem garnet terms previously in use, it is described as grossular-andradite by the GIA Gem Trade Laboratory. It can be distinguished from grossular by its absorption spectrum and (usually) higher refractive index; it can be distinguished from andradite by its lower R. I. The stacked parallel planes of growth zoning, always visible between crossed polarizers, are diagnostic of grossular-andradite. @chapter:7 @chapter:0 @chapter:7


# Publication Year: -
# Title: The Story Behind the Story:  China Revealed in 2013 Field Trip
# Abstract: The amount of .9999 fine gold jewelry at Batar Jewelry Company was beyond anything the team had ever seen before. Photo by Andrew Lucas, © GIA, courtesy of Batar Jewelry Company

The idea of a gem and jewelry exploratory trip to China was born ‒ as many industry ideas are ‒ from two colleagues walking a trade show.
Andrew Lucas, GIA manager of Field Gemology, and Dr. Tao Hsu, GIA technical editor of Gems & Gemology, attended the 2013 Tucson gem shows to gather up-to-date information on the colored stone industry for use as content for GIA’s Education courses. Hsu was relatively new to GIA at the time and Lucas learned she was born and raised in Beijing, China and graduated from the China University of Geosciences with a degree in gemology. She was soon sharing information about the Chinese gem and jewelry industry with him.
It wasn’t long before they realized that her connections and Mandarin language abilities would give GIA an excellent opportunity to document the Chinese industry. Several months later, a team that included Hsu, Lucas, GIA video producer Pedro Padua and GIA photographer Eric Welch, set off on a three-week journey to large and small gem and jewelry companies in China.
They were determined to learn as much about the Chinese industry as they could: What are they manufacturing? Who are they selling to? What’s in the domestic market? What are the trading and retail channels? They visited diamond cutting, colored stones (cutting and trading) and jade jewelry manufacturing facilities, as well as different forms of wholesaling and the retail aspects of the industry.

World-famous jewelry designer Shirley Zhang gave a personally guided tour of her factory and discussed her designs and the Chinese market with us. Photo by Eric Welch, © GIA
Lucas said he was amazed by many things he saw and learned in China, but the growth, scale and talent in the industry – and most importantly, the hospitality of the people they visited – made the greatest impression.
“I have been around the world, received great hospitality, and made many close friendships, but nowhere more so than China,” Lucas said. “Everyone was incredibly open and candid about their work. I found myself constantly saying ‘I love this country.’”
The Journey of Discovery
The modern jewelry industry in China only began approximately 30 years ago, Hsu said, but the country has a long history in jewelry.
“We started to use gold to decorate people and clothing 3,000 years ago and you can track jade back even longer,” she said. “Before 1912, there were rock shops and studios on a small scale that only served the royal family, not really the ordinary people. It was a totally different model. After the 1930s, China experienced a long upheaval period of about 50 years with World War II and the Cultural Revolution in between. No development of the jewelry industry happened within these 50 years.”
“That all changed in 1978 after the country re-opened. Then we started to learn from the Western world how to run a jewelry business,” she said. “This is a new era for the Chinese industry.”
The Chinese gem and jewelry industry is supported by a large pool of people with bachelor's, master's and doctorate degrees in gemology, which is offered as a major course of study at many universities, Hsu said. And the opportunities for these graduates grow every year.
“When I graduated 10 years ago, very few of us had the ambition to open a jewelry business,” she said. “But now many have that dream and take action to make it a reality right away because they see the economy and the market is growing so fast and a lot of opportunities are achievable.”
“It’s not that hard for you to start something for yourself. The broad view and the personal vision work together,” Hsu said.

Dr. Tao Hsu, technical editor of Gems & Gemology, meets with a member of the Chinese gem and jewelry industry. Photo by Pedro Padua, © GIA
This network of gemology alums were one of the most important ingredients for the GIA’s team to travel the country learning about the industry, Lucas said.
“Tao brilliantly planned and executed this ambitious trip through her former classmates and industry contacts,” Lucas said. “They all wanted to help with anything – logistics, anything we needed. This was especially true when we went to do interviews – they would say ‘you must go see this person’ or ‘I can help you with this.’ It’s almost part of their hospitality.”
The team traveled to the Shenzen, Panyu, Pingzhou, the Guangdong province (what many believe to be the jewelry manufacturing center of the world), to Shanghai (to better understand the commerce aspect of the industry) and Beijing (to document retailers and the highest-end of manufacturing).

“From Shenzhen to Guangzhou, we witnessed massive manufacturing and trading in colored stones, jade, jewelry and diamonds.” Lucas said. “The sheer scale of the industry was overwhelming. All around us were factories, trading centers and organizations to promote trade and government agencies to facilitate trade and retailers.”
“China supplies the world with jewelry,” Lucas said. “Shenzen has the largest 24K gold jewelry manufacturer in the world (it sold 200 tons of finished 24K gold jewelry in China alone last year), the largest diamond setting manufacturer in the world and one of the largest colored stone manufacturers in the world.”
"The country surpassed India not long ago as the major consumer of gold; are the second largest economy; the second biggest gemstone and jewelry market, and the second biggest luxury market," Lucas said. One jewelry retailer could have thousands of stores in a chain.

The China Diamond Exchange Center is where all diamonds, rough and cut, enter China.
Photo courtesy of China Diamond Exchange Center
“All of this growth is in the past 30 years,” Hsu said.
That growth power was most clear in Shanghai, Lucas said.
“Everywhere in the city spoke economic superpower to us,” he said. “This was also true of the China Diamond Exchange where Mr. Li Mu, vice chairman of the Diamond Administration of China, explained in detail the history and workings of the diamond industry in China.”
He also arranged for the team to visit one of the leading diamond jewelry retailer and Internet business operators, Zbird, where Lucas said he learned a lot about the bridal market.
“I didn’t realize China consumes 68% of all of the platinum in the world because it symbolizes how they feel about the purity in relationships,” Lucas said. “Platinum fits a lot of the personality of the Chinese consumer, so it caught on very quickly and is a tremendous seller.”

The brother and sister team of Zbird introduced the team to the bridal and internet diamond jewelry market in China. Image courtesy of Zbird
The People’s Perspective
The team was able to meet with business owners, designers and manufacturers throughout their journey who were very open to sharing information about their companies, their products and their lives.
“People were proud of their industry and they wanted to show us their industry,” Lucas said. “They wanted us to see as much as we could see. They wanted to share ideas. Most of the people were very curious about life in the U.S. compared to life there. They wanted to know what we thought of them and how we felt about our government.”
“Once they realized you have respect for their society and culture,” he said, “it was very easy to make very close friendships very quickly.”
Another strong trait Lucas noticed in the people he met, especially those in their mid-20’s, was a strong desire to gain education and knowledge.
“They had such a tremendous amount of focus and ambition, not just ambition to do well in business, but to do extremely well in whatever they do,” he said. “I saw that in the factories, too. The focus was amazing: they have a vision of where they want to be and they work hard at it and they have the patience for it. I found a tremendous amount of confidence in people for their future in China.”

An example of the vast jewelry manufacturing capability in China. Photo by Eric Welch, © GIA
A Clear Sense of Innovation
Lucas said that China for years had the bad rap of being “the knock-off country,” but he saw a lot of innovation and attention to quality and detail in the manufacturing facilities they visited.
“They would adapt some tried and true models of manufacturing that had been done in the West, but they would also implement different modifications and improvements so they could become more efficient,” he said. “A lot of the industry has moved away from massive amounts of workers ‒ though there’s still a lot of employment ‒ to more state-of-the-art technology in manufacturing.”
That sense of innovation was obvious with the designers they met, too.
“They are not just copying the West, which I think is the perception here,” Lucas said. “One jadeite designer I spoke to takes her inspiration from nature, from her culture and what she learns outside, and puts her own design element to it, blending them all.”
“I saw a lot of innovation in their designs and styles, including elements of individuality and originality in their artistic vision and techniques,” he said.
Reflections of Jade

The artistic talent and workmanship of the jadeite carvings in Pingzhou made a strong impression with the entire team. Photo by Eric Welch, © GIA, courtesy of Mazu
One of the most unforgettable experiences for the team was the two days they spent documenting the jade industry in Pingzhou and Sihui in Guangdong Province.
“The jade industry was extremely fascinating ‒ it’s just not something Westerners have a glimpse of very often,” said Lucas, who was surprised by the emotional and cultural connection people have to jade.

Hsu said there are two major materials of jade: Nephrite, which goes back thousands of years ago, and jadeite, which was first imported in about 1870. She said people first used jade to make tools because it was easy to shape, but then started to use it as worship vessels in different ceremonies since it was pretty compared to other stones.
“They used it to worship their ancestors in different ceremonies. Then it gradually became a decoration and people carved it to give it more meaning,” she said. The patterns gradually evolved; traditional patterns or shapes have different meanings, such as peace or good luck.
“We play with it – it’s not like a piece of jewelry that you wear when you go out – we have it in our hand, we play with it every day,” she said. “People think they are a part of the jade piece and it is a part of them. It’s totally mingled.”

Chinese people enjoy the texture and color of jade, Hsu said, but can like it for any reason, like the feeling you get when you touch it. “We worship how nature can make it look that way,” she said.

Hsu said that jade is also a reflection of the Chinese people.

“Chinese are very conservative and the jade is the same – it matches with our personality,” she said. “It’s not sparkling or transparent, so you cannot see through it easily. That’s also like a lot of Chinese people – they are conservative, too, and you cannot see through them right away. We prefer to be like that based on our culture and tradition.”

“When you look at the nephrite, you want yourself to be like that,” she said.

The GIA team spent endless hours documenting the Chinese gem and jewelry industry. Photo by Eric Welch, © GIA
Consumer Market
The team not only got an insider’s look at the creators of Chinese jewelry, but also a clear understanding of the Chinese consumer.
“The really fascinating part of our trip was seeing the explosion and growth in the domestic consumption,” Lucas said. “The Chinese consumer is interested in everything.”
That’s because they have had the opportunity to travel the world to see all of the different types of gemstones and materials others are wearing, Hsu said. “So people brought them back and more people got to know these materials.”
“Just in the past 5-10 years, people started to realize how beautiful colored stones are,” she said. “Once they saw that, the market started to explode.”
Lucas sees tremendous opportunity for these sales to keep growing as the number of people born in China in the 1980s is three times the size of the Baby Boomer market in the U.S.
“That’s why it was so important for us to go on this exploratory trip,” he said. “Not only are the Chinese a gracious and hospitable people, but they have the power to help the gem and jewelry industry continue to thrive.” @chapter:47 @chapter:3 @chapter:47


# Publication Year: 2013
# Title: Dictionary of Gemstones & Jewelry
# Abstract: The late Akira Chikayama was a noted gemologist who considered the Dictionary of Gemstones & Jewelry his personal “world heritage.” Indeed, the very scope of this dictionary is impressive. Entries include gems, minerals, sources, synthetics, treatments, jewelry findings, tools used in gem cutting and jewelry making, famous gemologists, scientists, mineralogists, and artists—the list goes on.
A massive undertaking to begin with, the book was translated from Japanese to English. But it did contain some minor errors. In the listing for the Searcy diamond, for example, there appears a photo of the Sancy. In the entry for “abraded culet,” the author likened it to an open culet, which I do not agree with. And seeing entries on Gübelin, Kunz, and Shipley made me wonder why Dana, Liddicoat, and Sinkankas were not included.
But as a general reference, the book serves its purpose well. The appendices alone are useful, covering a wide range of subjects and providing charts on birthstones, ring sizes, hallmarks, and more. Overall, this volume would make a nice addition to any gemological library if cost is not an issue.
Reviewed by Jana Miyahira-Smith
GIA, Carlsbad @chapter:23 @chapter:2 @chapter:23


# Publication Year: -
# Title: New Tool for Diamond Appearance Research
# Abstract: The L-Box™ can be used to compare the appearance of two or more diamonds, or fitted with a camera to capture a series of photos while the objects are moving. The images can be combined to build a high-resolution or 3D movie. @chapter:41 @chapter:1 @chapter:41


# Publication Year: -
# Title: Pre-Basel Show Price Increases Affect Gemstone Sales
# Abstract: The new gem hall at BaselWorld was configured similarly to the previous site, but smaller, with one entrance from the main fair. Photo by Russell Shor.

                      Business at the April 24-May 2 BaselWorld Fair was slower than expected as Asian buyers proved scarce, Europeans struggled with a slow economy and investment buyers turned a cautious eye toward the lofty prices of top gemstones.

This year’s show featured a much greater selection of top fancy-colored diamonds than previous years – vivid and intense pinks and blues, even a large intense green – but buyers willing to pay the million-dollar-plus per carat prices were scarce. The asking rates reflected the fact that, just before the show, several fancy-colored diamonds achieved record prices at well-publicized auctions. (A 5.30 carat Fancy Deep blue diamond, for example, sold for $9.5 million – $1.8 million per carat – at Bonham’s London on the day the Basel show opened.) In previous years, a number of ultra-wealthy private buyers from Asia, the Middle East and Russia attended the Basel show to buy such stones and large colorless diamonds.

Diamond dealers who did well were offering middle and lower quality colorless diamonds and smaller fancy yellow goods; these gems are normally not in abundance at Basel because show expenses far exceed other venues.

High-quality colored stones were also a difficult sell because prices for unheated Burmese ruby and sapphire, as well as Colombian emerald, increased by 20-30% in the months leading up to the show. Emeralds from other locales, however, were in strong demand due to fashion magazines touting green as the year’s most popular color for accessories.

The scarcity of Chinese buyers was certainly another factor for the slow show. These buyers helped the luxury watch companies – the main exhibitors at BaselWorld – achieve record sales last year. But watch company executives said sales this year were down 30% or more because many Chinese buyers stayed home. The reason they cited, beyond a slowdown in the country’s economic growth, was the anti-corruption campaign of the country’s premier Xi Jinping. Luxury watches, and to a lesser extent, diamonds, had been a favorite “gift” item to grease the wheels of China’s government – so much so that nearly a quarter of all Swiss luxury watch exports went there.

Gem dealers also thought the new location of the gemstone hall, which was poorly marked and difficult to access from inside the show, also helped blunt sales.

“Every year we have a few luxury watch buyers visit the gem hall for a look. Sometimes this translates into sales,” one major diamond exhibitor said. “I wouldn’t say it is a major factor, but it can make enough of a difference to turn a slow show into a decent show.”

Another dealer noted that price volatility of polished diamonds over the past year deterred a number of luxury watch companies from producing as many diamond watch lines as they had in the recent past.

“They’ve already had to deal with gold price fluctuations and don’t want to add 20% variations in diamond prices. They don’t want to deal with both at the same time,” said one diamond supplier.

The buying was somewhat better in the designer jewelry halls, particularly because more American retailers were in attendance than in recent years (despite the high rate of the Swiss franc). Retailers said they were looking for pieces to set them apart from Internet competitors. @chapter:37 @chapter:3 @chapter:37


# Publication Year: 1993
# Title: De Beers near Colorless-to-Blue Experimental Gem-Quality Synthetic Diamonds
# Abstract: Examination of five small boron-doped synthetic diamonds, grown by De Beers researchers for experimental purposes, reveals some diagnostic features not reported in previous studies of gem-quality synthetic diamonds. The presence of internal growth sectors that are blue, yellow, or near colorless has produced faceup colors in three faceted stones that vary from near colorless to bluish-greenish gray to blue. Because they look so different from previously reported De Beers synthetic diamonds, such faceted synthetics could go unrecognized without careful gemological testing should they ever become commercially available. @chapter:36 @chapter:1 @chapter:36


# Publication Year: 2010
# Title: Update on Mexifire Synthetic Fire Opal
# Abstract: As a result of changes in the manufacturing process, recent production of the synthetic fire opal marketed as “Mexifire” exhibits some new properties. While the earlier material could be identified on the basis of low RI and SG values, the new synthetics have values that are quite similar to—and partially overlap those of—natural fire opals. With the change in the manufacturing process, the water content has also changed, as reflected in the IR spectra. @chapter:48 @chapter:0 @chapter:48


# Publication Year: 2021
# Title: Fourth Annual Gianmaria Buccellati Foundation Award
# Abstract: Belle Sin Ting Wong received the Gianmaria Buccellati Foundation Award for Excellence in Jewelry Design for her diamond, sapphire, pearl, jadeite, and enamel brooch, inspired by the Siamese fighting fish. Photo by Johnny Leung and Tony Leung.

Belle Sin Ting Wong, a graduate of GIA’s Jewelry Design program in Hong Kong, received the fourth annual Gianmaria Buccellati Foundation Award for Excellence in Jewelry Design. This year, the prestigious award was announced virtually due to the global pandemic shuttering the Tucson gem shows. Sin Ting Wong (see above) was one of nine finalists selected from a competing group of more than 100 students from GIA’s seven campuses. Her winning design was inspired by the Siamese fighting fish and features diamond, sapphire, pearl, jadeite, and enamel set in 18K yellow and white gold.
Sin Ting Wong hopes to raise environmental awareness through this brooch design and advocates the use of sustainable products or “we might be very close to losing these beautiful creatures and quicken the pace of global warming.”
She will travel to Italy, where she will have the opportunity to meet Rosa Maria Bresciani Buccellati, the president of the foundation.
Laurie Bailyn, GIA senior manager of jewelry manufacturing arts, said, “It is incredible that so many students managed to complete their Jewelry Design studies in 2020, despite the challenges of the global pandemic. Many of the beautiful, original designs that students created this year were inspired by themes of connection and community.”

The 2021 Gianmaria Buccellati Foundation Award for Excellence in Jewelry Design competition is currently open to GIA Jewelry Design students who meet the eligibility requirements. For more information on entering the competition, visit gia.edu/buccellati-foundation-award-jewelry-design @chapter:45 @chapter:2 @chapter:45


# Publication Year: 2014
# Title: Spinel Inclusion in Spinel
# Abstract: Figure 1. This 26.73 ct dark pink-purple spinel contained a spinel crystal inclusion. Photo by Robison McMurtry.

A 26.73 ct transparent dark pink-purple oval mixed cut (figure 1) was submitted to the Carlsbad laboratory for identification services. Standard gemological testing showed a refractive index of 1.719 and a hydrostatic specific gravity of 3.59. The stone fluoresced very weak red to long-wave UV light and was inert to short-wave UV. Observed using a handheld spectroscope, the stone showed thin absorption bands near 680 nm, with fine absorption lines near 670 nm. These gemological properties were consistent with spinel.

Figure 2. Under diffused lighting, the outline of the spinel crystal was only partially visible. Photomicrograph by Ziyin Sun; image width 3.70 mm.
Interestingly, microscopic examination showed that the spinel was relatively free of inclusions except for a very low-relief solid inclusion that was only partially visible (figure 2). Examination with polarized light (figure 3) revealed the entire outline of the low-relief crystal. Unaltered crystals generally provide strong evidence that a stone has not been heated, and this inclusion showed no alteration. But it is also important to consider the identity of certain inclusions when using them as an indication for thermal treatment. Due to the low relief of this inclusion, it is very likely a spinel inside of spinel. Their matching refractive index explains why the inclusion is nearly invisible. Since the host and inclusion are the same material, we would not expect to see any alteration due to heat treatment. Therefore, the unaltered appearance of this inclusion cannot be used to determine that this spinel has not been heat treated.

Figure 3. Under polarized lighting, the outline of the spinel crystal was clearly visible. Photomicrograph by Ziyin Sun; image width 3.70 mm.
The spinel’s visible absorption spectrum revealed that its purple color results from the combination of Fe and Cr (figure 4). Absorption bands with a maximum at 400 and 550 nm are caused by Cr3+ (D.L. Wood et al., “Optical spectrum of Cr3+ ions in spinels,” The Journal of Chemical Physics, Vol. 48, No. 11, 1968, pp. 5255–5262). Fe2+ causes the absorption band from 400 to 590 nm, while the Fe2+/Fe3+ charge transfer and Fe2+ cause the absorption bands from 590 to 700 nm (S. Muhlmeister et al., “Flux-grown synthetic red and blue spinels from Russia,” Summer 1993 G&G, pp. 81–98).

Figure 4. The spinel’s visible spectrum revealed that its dark pink-purple color was caused by Cr and Fe.
Spinels submitted to GIA’s laboratory are routinely checked using advanced analytical tools. Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) was used to confirm the natural trace elements. Higher concentrations of Li (27.7 ppmw), Be (87.4 ppmw), Zn (133 ppmw), and Ga (63 ppmw) indicate a natural origin, and the specimen’s photoluminescence (PL) spectrum was consistent with a heated spinel due to the broad full width at half maximum (FWHM) observed at 687.5 nm (figure 5; see S. Saeseaw et al., “Distinguishing heated spinels from unheated natural spinels and from synthetic spinels,” GIA Research News, April 2009, http://www.gia.edu/gia-news-research-NR32209A). It was unusual to see a spinel with this dark pink-purple color showing evidence of heat, as we typically see only red spinels that have been heated. From careful microscopic examination and advanced gemological testing, we were able to conclude that this was a natural spinel showing indications of heating.

Figure 5. The gray spectrum of unheated spinel shows that the FWHM (full width at half maximum) of the peak with highest counts is 0.92 nm and the position of the peak is at 685.5 nm. The purple spectrum, representing the dark pink-purple spinel, shows that the FWHM of the peak with highest counts is 6.11 nm and the peak is shifted from 685.5 to 687.5 nm. @chapter:26 @chapter:0 @chapter:26


# Publication Year: 2018
# Title: Unique Star Sapphire with Transparent Core
# Abstract: Figure 1. This 34 ct sapphire cabochon has a yellow pseudohexagonal window surrounded by metallic-looking material that displays asterism. Photo by Shunsuke Nagai.

GIA’s Tokyo laboratory recently examined a 34 ct oval cabochon of unique appearance. This cabochon consisted of a transparent yellow pseudohexagonal core in an opaque metallic-looking area (figure 1). Spot refractive indices (RIs) on both areas were 1.76, and specific gravity (SG) was 4.04. This appearance of a transparent yellow window with an opaque metallic surrounding area is reminiscent of pallasitic peridot, an olivine nodule enclosed in nickel-ion alloy of stony-iron meteorites (see J. Sinkankas et al., “Peridot as an interplanetary gemstone,” Spring 1992 G&G, pp. 43–51). However, no surface discontinuity between these two parts can be found with close observation under reflected light. Furthermore, this metallic-looking area exhibited six-rayed asterism. Under the microscope, negative crystals in a plane and healed fissures were found in the transparent area; densely packed needle-like inclusions, some crystals, and stained fissures were seen in the opaque area (figure 2). In addition to the microscopic observations, advanced testing of the yellow part revealed that this specimen was a natural corundum. The metallic appearance and asterism were caused by the strong reflection from the dense needle-like inclusions (figure 2), some of which were flat. These needles were identified as hematite and ilmenite by Raman spectroscopy. The slightly elevated SG of this specimen might have been caused by the abundance of these inclusions, since the SGs of both hematite and ilmenite are higher than that of corundum.

Figure 2. The sapphire’s yellow core includes negative crystals and healed fissures (left) and the metallic-looking part (right) has dense needles. Photomicrography by Makoto Miura; field of view 3.38 mm.
As previously documented (e.g. T.N. Bui et al., “From exsolution to ‘gold sheen’: A new variety of corundum,” Journal of Gemmology, Vol. 34, No. 8, 2015, pp. 678–691; N. Narudeesombat et al., “Golden sheen and non-sheen sapphires from Kenya,” Gem and Jewelry Institute of Thailand, July-August 2016, pp. 282–288; Winter 2016 Lab Notes, pp. 413–414), sapphires with golden shimmer caused by hematite needles are known as “golden sheen” or “Zawadi” sapphires in the trade. As with rutile needles in common star sapphires, hematite needles intersecting at 60 degrees can cause six-rayed asterism. Golden sheen sapphires sometimes have densely included parts, but such a distinct zoning of transparent and densely included parts has not been documented. This unique appearance may indicate a certain crystallizing condition of sapphires. @chapter:24 @chapter:0 @chapter:24


# Publication Year: -
# Title: A Study of Rubies from Cambodia and Thailand
# Abstract: Rough and faceted rubies from Thailand-Cambodia. The rubies in matrix are associated with green pyroxene. The faceted stones in the center weigh 2.25 and 1.62 carats. Photo by Vincent Pardieu © GIA.

Although miners have exploited ruby deposits around the Thai-Cambodian border for more than a hundred years, activity was most intensive between the 1960s and 1990s. This period coincided with a military coup in Myanmar (Burma) that made that country’s gem deposits largely inaccessible to world markets. As a result, Thailand was ideally placed to take on the mantle of the world’s premier commercial ruby source. Later in the 1990s, the Thai-Cambodian deposits became depleted and new ruby sources elsewhere came on stream. Since then, activity has declined and most mines are abandoned. Although current production is sporadic, gems from these once commercially-important deposits are present in the marketplace and in jewelry.

A new report from the GIA Laboratory in Bangkok, ‘A Study of Rubies from Cambodia and Thailand’ characterizes gems from these once prolific deposits. This study used 41 purplish-red ruby samples obtained by GIA’s Field Gemology Department in previous field expeditions: 34 from Pailin, Cambodia and 7 from Chanthaburi-Trat. The samples were fashioned to optimize them for LA-ICP-MS chemical analysis, UV-Vis-NIR and FTIR spectroscopy, and inclusion studies using microscopy and Raman spectroscopy.

Thai rubies are associated with alkali-basalt deposits in Chanthaburi, Trat and Pailin. These basalt-related gems have a very high iron (Fe) content and very low fluorescence as a consequence. Due to their high Fe content, Thai-Cambodian rubies typically have a purplish aspect, and UV-Vis-NIR spectra show a combination of both chromium and iron chromophores. To remove this purple aspect, and heal any potential fractures, rubies from these deposits are routinely heat-treated.

Minerals like diopside, negative crystals surrounded by fluid fingerprints or thin films, naturally-healed fractures, and intersecting polysynthetic twinning planes with growth tubes are among these rubies most distinctive internal characteristics. LA-ICP-MS analysis showed that comparison of gallium, magnesium, and vanadium content with the trace element chemistry of iron-rich rubies from amphibolite-related deposits is helpful for origin determination.

The authors suggest a combination of techniques—trace-element chemistry and microscopy—can readily separate Thai-Cambodian rubies from Kenyan basalt-related rubies and those originating in amphibole-related deposits. @chapter:6 @chapter:0 @chapter:6


# Publication Year: 2022
# Title: A Reported Cassis Pearl from Key West, Florida
# Abstract: Figure 1. This oval pinkish orange porcelaneous pearl weighing 29.78 ct and measuring 17.86 × 15.64 × 14.58 mm was reportedly found in a queen helmet conch (Cassis madagascariensis), shown on the left with various Cassis species shells. Photo by Robert Weldon. Shells courtesy of Robin Willis.

Figure 2. Left: This porcelaneous pearl exhibited a fine, well-formed flame structure covering the entire surface, and a homogeneously spotted pattern was visible with the unaided eye. Photo by Robert Weldon. Right: Under magnification with fiber-optic illumination, the wide and spiky flame structure was evident. Photo Artitaya Homkrajae; field of view 2.90 mm.
The Carlsbad laboratory recently examined an oval non-nacreous pearl weighing 29.78 ct and measuring 17.86 × 15.64 × 14.58 mm (figure 1). The pearl possessed a uniform pinkish orange bodycolor and a porcelaneous surface with flame structures. The flames were short and wide and tapered to a point. This fine, well-formed flame structure looked like a homogeneous spotted pattern throughout the pearl’s surface (figure 2, left), yet the flame forms were evident at high magnification under the microscope (figure 2, right). Subsequently, Raman spectroscopic analysis with a 514 nm argon-ion laser verified the pearl was composed of aragonite, with peaks at 154, 181, 192, 207, 704, and 1085 cm–1 (J. Urmos et al., “Characterization of some biogenic carbonates with Raman spectroscopy,” American Mineralogist, Vol. 76, 1991, pp. 641–646); two strong polyene peaks at 1131 and 1523 cm–1 were indicative of natural color (C. Hedegaard et al., “Molluscan shell pigments: An in situ resonance Raman study,” Journal of Molluscan Studies, Vol. 72, No. 2, 2006, pp. 157–162). Real-time microradiography (RTX) revealed a dark gray oval void-like feature in the center and a growth ring in the outer area of the pearl (figure 3). Such a void can be found in natural pearls from a number of porcelaneous pearl-producing mollusks.

Figure 3. RTX imaging revealed the growth structure of the pearl: an ovalish void-like feature of less radiopacity in the center and a growth ring in the outer area. Image by Amiroh Steen.

Figure 4. This photo shows the pearl and the queen helmet shell in which it was found. Photo courtesy of the Bert Matcovich family.
Orange porcelaneous pearls are produced from various marine gastropod species such as queen conch (Lobatus gigas), Melo species, Cassis species, and horse conch (Fasciolariinae subfamily). The flame characteristics and pinkish orange bodycolor of this pearl were unlike those of orange porcelaneous pearls previously submitted to GIA. The client who submitted the pearl stated that it was found inside a queen helmet conch in the early 1960s by Bert Matcovich (figure 4), who owned a shell shop in Key West, Florida. Born into a family of shellers with more than 60 years of experience, Matcovich fished the waters off Key West for conchs and visited local shrimp boats daily in the 1960s to purchase various types of shells. This pearl was a remarkable discovery.
Queen helmet, also known as emperor helmet, is the common name for a marine gastropod species called Cassis madagascariensis, which belongs to the Cassidae family. The species is generally distributed in the tropical western Atlantic, including the Caribbean Sea (J.H. Leal, “Gastropods,” in K.E. Carpenter, The Living Marine Resources of the Western Central Atlantic, Vol. 1, Rome: Food and agriculture organization of the United Nations, 2002, pp. 99–127). Queen helmet shells have large, thick whorls with short spires, and three rows of knobs often appear on the body. They have a flat large parietal shield next to an aperture, and the color ranges from pale cream to deep salmon, often with a dark orangy brown color between the “teeth” (see again figure 4). Owing to their significant thickness, these colorful shells are widely used for cameo carving.
Cassis pearls typically have a fine and slender flame structure, often with intersecting flames. Their colors traditionally range from light orange to orangy brown, sometimes with patchy color. This pearl was unlike typical Cassis pearls examined by GIA, and its mollusk identity could not be confirmed with gemological testing. Nonetheless, this fine large natural non-nacreous pearl and its discovery story from six decades ago are noteworthy. @chapter:11 @chapter:4 @chapter:11


# Publication Year: 2023
# Title: Rainbow Mountain in Natural Diamond
# Abstract: These iridescence features observed in a 1.71 ct natural diamond (top) were reminiscent of Rainbow Mountain in Peru (bottom). Photomicrograph by Tejas Jhaveri; field of view 2.90 mm. Bottom photo courtesy of Daniel Sánchez Ibarra (Wikimedia Commons).
At GIA, we occasionally see diamonds with inclusions that resemble natural objects. A breathtaking example was recently observed in a 1.71 ct, H-color, I2-clarity natural diamond. The deep feather in the figure above (top) shows an iridescence feature resembling Montaña Arcoíris (Rainbow Mountain) in the Andes Mountains of Peru (see above, bottom). Thirty years ago, a diamond with a similar feature (Summer 1993 Lab Notes, pp. 123–124) was described as having iridescence due to a thin-film separation caused by a “V”-shaped dislocation.
As with the previously described diamond, the iridescence in this diamond is only visible at some orientations. This memorable effect showcases the beauty of the natural world within the diamond. @chapter:39 @chapter:1 @chapter:39


# Publication Year: 1981
# Title: The Hidden Beauty of Amber: New Light on an Old Subject
# Abstract: While many aspects of the nature of amber and its organic inclusions have been reported in the literature, virtually nothing has been recorded about the inorganic - mineral, liquid, and gas -inclusions "hidden" amid the better-documented life forms. This article takes a microscopic look at the gas bubbles and crystal forms that also belong to amber's inner world. With the use of polarized light, the author also documents strain centers in the amber, including movements made millions of years ago by animals trapped in the resin. @chapter:46 @chapter:4 @chapter:46


# Publication Year: 2022
# Title: Cat’s-Eye Paraíba Tourmaline with Copper Inclusions
# Abstract: Figure 1. This 1.33 ct cat’s-eye Paraíba tourmaline with copper inclusions shows a golden chatoyancy. Photo by Shunsuke Nagai.
The Tokyo laboratory recently received a 1.33 ct greenish blue oval cabochon measuring 6.83 × 6.17 × 3.55 mm (figure 1) and displaying a cat’s-eye effect. Standard gemological testing yielded a refractive index of 1.620–1.640, a uniaxial optical sign, and a hydrostatic specific gravity of 3.08, all consistent with tourmaline. Ultraviolet/visible/near-infrared spectrometry showed the absorption band at 900 nm, which is greater than the one at 700 nm, indicating the greenish blue color of this sample was dominated by copper (P.B. Merkel and C.M. Breeding, “Spectral differentiation between copper and iron colorants in gem tourmaline,” Summer 2009 G&G, pp. 112–119). This stone meets the requirement for designation as a Paraíba tourmaline (Laboratory Manual Harmonisation Committee Information Sheet #6, 2012). Laser ablation–inductively coupled plasma–mass spectrometry indicated a high copper concentration of 11741–14794 ppmw. The high copper (over 10000 ppmw) is limited to Brazilian origin (Y. Katsurada et al., “Geographic origin determination of Paraíba tourmaline,” Winter 2019 G&G, pp. 648–659).
As previously reported (Winter 2018 Lab Notes, pp. 438–439), cat’s-eye Paraíba tourmaline usually includes groups of parallel tube-like inclusions that create the phenomenon. However, that was not the case for this tourmaline.

Figure 2. The copper inclusions on the lower right are partially reflecting light. Photomicrograph by Yuxiao Li; field of view 3.5 mm.
Different from normal cat’s-eye Paraíba tourmaline, the band of reflected light in this stone was stronger, with metallic luster. Microscopic examination revealed a fluid inclusion network, rounded metallic inclusions, and growth tubes, with many golden-colored dendritic inclusions causing the cat’s-eye effect (figures 2 and 3). Raman spectroscopy could not be used to identify the inclusions, which were too thin and did not reach the surface. Such inclusions in Paraíba tourmaline have been reported and identified as natural copper (F. Brandstätter and G. Niedermayr, “Copper and tenorite inclusions in cuprian-elbaite tourmaline from Paraíba, Brazil,” Fall 1994 G&G, pp. 178–183). The natural copper inclusions were aligned in the same direction, parallel to each other, and reflected the light to cause the chatoyant effect. This also explains why the reflective light band in this stone looked different from other cat’s-eye Paraíba tourmaline.

Figure 3. The copper inclusions aligned in the same direction appear brownish and black (left) and together display golden luster when the light enters from a certain direction (right). Photomicrographs by Yuxiao Li; field of view 2.3 mm.
While some cat’s-eye Paraíba tourmalines have been examined in GIA laboratories, this is the first with chatoyancy caused by copper inclusions. @chapter:7 @chapter:0 @chapter:7


# Publication Year: 2014
# Title: Tucson 2014 Overview
# Abstract: View Gallery

Tucson draws buyers hungry for Earth’s treasures.
Every February, exhibitors and buyers from all over the globe descend on Tucson, Arizona, for the annual gem and mineral shows that take place in conference spaces, tents, hotel rooms, and parking lots across the city. This year a number of exhibitors noted the lack of Chinese buyers, who are now likely to make their purchases at the Hong Kong show for convenience. For many exhibitors, however, Tucson remains a very important venue in the year’s trade show calendar.

For Alexander Wild (Wild & Petsch Lapidaries, Kirschweiler, Germany), the show was a place to write invoices and do “serious selling.” While many clients were not shopping for any one particular gem, they were seeking out unique items: fine-quality gems as single pieces, matched pairs, sets, or suites. Exhibitors selling everything from cultured pearls to unheated tanzanite, Australian chrysoprase, and top-quality ruby, sapphire, and emerald echoed the same sentiment: fine goods were strong sellers.

Wild attributed the current shortage of gem rough to the global economic crisis that began in September 2008. The following years, he recalled, were “disastrous” for many in the colored gem trade, as their customers simply stopped buying. The resulting lack of liquidity cascaded down to active mining operations, especially in Africa and Brazil. Miners in those areas were left with no clients for their previously mined goods, and no income with which to purchase equipment or staples such as diesel fuel. Within a short time, Wild said, many operations were saddled with debt and subsequently ceased operations. Mine workers returned to the agricultural sector, which began to rebound in 2009. By then, costs had become so prohibitive that many former operators could no longer afford to return to the mining industry.

	Hans Juergen AlthoeferEmil Kreis & Co.

Hans Juergen Althoefer of Emil Kreis and Co., explains how changes in the colored stone market are reflected in the stock his company carries. While business was formerly concentrated on smaller calibrated goods, clients now demand more unique ‘one-of-a-kind’ pieces along with matched pairs and sets.
One common refrain among exhibitors was the intense competition for scarce cutting rough, creating a dramatic price increase. Many mentioned stiff competition from Chinese buyers or their agents at the sources. Steve Ulatowski of New Era Gems (Grass Valley, California) told us the price of pink to red tourmaline rough has shot up due to Chinese demand. He cited Nigerian tourmaline rough that was priced at $8,000 per kilogram several years ago; the current asking price for equivalent goods was $200,000 per kilo, with sellers asking for cash on the table.

Many dealers also emphasized the importance of “recirculated” gems or jewelry pieces, remarking on the high quality of pieces in the secondary market. These included fine sapphire, ruby, alexandrite, and cat’s-eye chrysoberyl, gems that were otherwise unobtainable. All find a ready market in Asia.

Regardless of these powerful undercurrents, most of the exhibitors who spoke with us expressed satisfaction with their results from Tucson. Although traffic at some shows was down from previous years, exhibitors reported that buyers were serious and business was satisfyingly brisk.

All in all, the Tucson gem and mineral shows are a fascinating cross section of materials, sellers, and buyers that provides a unique window into a singular industry. We eagerly look forward to next year’s shows.

G&G appreciates the assistance of the many friends who shared material and information with us this year, with special thanks to the American Gem Trade Association for providing photography studio space during the AGTA show. GIA’s Eric Welch, Pedro Padua, Clara Zink, and Andy Lucas contributed to this report. @chapter:38 @chapter:3 @chapter:38


# Publication Year: 2020
# Title: Man-Made “Inclusion”?
# Abstract: Figure 1. Fiber inside a cavity filled with liquid resin in a cushion-cut emerald measuring 8.2 × 7.3 × 3.1 mm. Photomicrograph by Holman Alvarado.
Two important internal features in gemstones are inclusions and fissures. Inclusions are an important source of information in the gemological evaluation process. They can often provide indications about geographic origin (see, e.g., S. Saeseaw et al., “Three-phase inclusions in emerald and their impact on origin determination,” Summer 2014 G&G, pp. 114–132); growth conditions (e.g., A. Cheilletz et al., “Time-pressure and temperature constraints on the formation of Colombian emeralds: An 40Ar/39Ar laser microprobe and fluid inclusion study,” Economic Geology, Vol. 89, No. 2, 1994, pp. 361–380; J.G. Toloza et al., “Similarities and differences between fluid inclusions hosted by Colombian emeralds,” Special Issue on the 15th IAGOD Symposium, 2018, pp. 166–167); natural or synthetic origin (e.g., N.D. Renfro et al., “Chart: Inclusions in natural, synthetic, and treated emerald,” Winter 2016 G&G, pp. 402–403); and whether the stone has been treated to improve clarity.
Fissures are openings in the stones, and those “empty” spaces affect clarity in a negative way. Therefore, gemstones are treated to fill those gaps with different substances. Fillers can generate physical phenomena that resemble natural inclusions and may be misleading to the untrained eye.
Emeralds are most commonly enhanced with fissure filling. Fillers in emerald are identified by looking at the flash of color (blue, violet, orange, and yellowish) shown when the transmitted light of the microscope hits the inclusions or with the use of FTIR or Raman spectroscopy.

Figure 2. Fiber seen inside the cavity under 365 nm UV light at 50× magnification. Photomicrograph by Luis Gabriel Angarita.
Recently the authors identified a man-made “inclusion” in a 1.15 ct cushion-cut Colombian emerald (figure 1) measuring 8.2 × 7.3 × 3.1 mm. It displayed a typical yellow flash most commonly seen in emeralds filled with liquid resin, which was later corroborated by FTIR spectroscopy. The “inclusion” was barely visible and almost transparent under regular microscope light sources (transmitted and reflected). Therefore, a 365 nm UV light was employed to check whether the foreign object fluoresced, and in fact it did (figure 2).

Figure 3. Three fibers under 365 nm UV light. A: Cotton handkerchief used to remove oil from the surface of the stone. B: Net fiber in which emeralds are placed for the enhancement process. C: Jewelry cleaning cloth also used to remove oil from the surface. Photomicrograph by Javier Toloza.
In the authors’ opinion, the fiber could only have come from one of three sources: a cotton handkerchief, a microfiber jewelry cloth, or the net used during the immersion of the stones in the enhancement container of the oiling machine. The first two would imply that a piece of fiber got stuck to the surface of the stone before the enhancement procedure took place, which is highly unlikely. The third source seemed the most plausible. In order to test that hypothesis, three strains of fibers were collected and compared using Raman spectroscopy with a Horiba HR Evolution with the laser operating at 532 nm. Although the spectra showed peaks in the 500 to 1500 cm–1 range, they were not specific for either of the fibers. Using the Olympus BX 41 microscope at 1000×, the diameter of the fiber was measured, and there was consistency with the diameter of the fiber collected from the net, about 50 μm. A 365 nm UV light source was also used to differentiate among them. A clear difference was evident between the nylon fiber from the net and the other two fibers (figure 3). This second test corroborated the authors’ hypothesis. @chapter:10 @chapter:0 @chapter:10