# Publication Year: 2018
# Title: Colored Stones and Pearls
# Abstract: Figure 1. A single tourmaline fiber contains three distinct chemical zones, each recording the fluid composition at the time of growth. Between zones, fluids dissolved preexisting tourmaline to provide components for the new species in equilibrium. This overall compositional trend mimics the fractionation trend in a pegmatite.

Tourmaline: A Gemstone’s Guide to Geologic Evolution of the Earth’s Crust
Barbara L. Dutrow
Louisiana State University, Baton Rouge
Tourmaline is recognized as an important gemstone and a stunning collector’s item, and each crystal contains geochemical fingerprints that can elucidate an astonishing array of geological processes. Through field, experimental, analytical, and theoretical studies, the rich chemical signature encapsulated in tourmaline is being unraveled and revealed. Because of its widely varying chemistry, tourmaline is particularly adept at recording the host-rock environment in which it grew, be it a melt, a marble, or a former subduction zone. In addition, it can record the thermal and baric conditions of its growth, acting as a geothermometer or geobarometer. A crystal that exhibits sector zoning can provide the complete temperature history of its growth, serving as a single-mineral thermometer. Other tourmaline compositions may reveal the absolute age of a geologic event that produced tourmaline formation.
Tourmaline also excels at recording the evolution of the fluids with which it interacts. Its essential ingredient is boron (B), a fluid-mobile element. Thus, tourmaline is nature’s boron recorder. Tourmaline formation and growth reflects the availability of boron to the rock system. Fluids can be sourced internally from the melt or from the breakdown of other B-bearing minerals, or fluids with boron can infiltrate the rock system from external sources. In each case, tourmaline preserves signatures of these events in the form of new growth, dissolution of preexisting tourmaline with growth of a new tourmaline composition (tourmaline cannibalizing itself to form anew), or replacement of another mineral. Tourmaline species may hint at fluid compositions. For example, species ranging from oxy-dravite to povondraite are typically found in saline, oxidizing environments and are indicators of these fluids in the geologic past. The deep green chrome (Cr) tourmalines reflect an unusual environment enriched in both Cr and B. Similarly, tourmaline compositions may reflect specific components of the fluid phase and, in some cases, provide quantitative estimates of fluid compositions (figure 1). Fitting data to tourmaline–fluid partitioning experiments permits calculation of the sodium (Na) concentrations in the coexisting fluid phase, and suggests that the alkali species of tourmaline—elbaite, dravite, and schorl—form in fluids with greater than 0.30 mol/L Na, whereas the vacancy-dominant species, foitite and oxy-foitite, are stable in fluids with less than 0.25 mol/L Na. Once formed, tourmaline resists attack by corrosive acidic fluids.
Combining these features, tourmaline is a mineral containing unparalleled information on the environment in which it grew and the geologic processes responsible for it. An advantage of tourmaline as a geologic record keeper is that once these signals are incorporated, they are retained throughout the “lifetime” of the grain due to its slow volume diffusion. In some extraordinary cases, a single tourmaline grain can record its complete “life cycle,” from its original crystallization from a cooling magma deep within the crust through the rock’s uplift, cooling, and partial destruction during erosion to deposition and reburial followed by heating and regrowth in a new geologic environment. The oldest known tourmaline dates back about 3.7 billion years, and it retains the chemical growth zones from its formation in early Earth, thus elucidating the presence of boron-bearing fluids and continental crust during that time.
The totality of this embedded geologic history is the result of tourmaline’s flexible crystal structure, which incorporates a substantial number of chemical elements and isotopes, across a wide array of sizes and valence states, and in quantities from major to trace amounts. Such variable chemistry not only produces a kaleidoscope of colored gemstones but also permits tourmaline to be stable over nearly all pressure and temperature conditions found in Earth’s crust, and to develop in all major rock types, from solidified igneous melts and pegmatites to metamorphic and sedimentary rocks. This chemical variability classifies tourmaline as a mineral supergroup, currently consisting of 33 different species, each with a different and unique story.
Telling tourmaline’s story typically requires chemical compositions to be obtained. New methods involving laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) and infrared and Raman spectroscopy, along with well-established techniques such as electron microprobe analysis, provide such information to gemologists and geologists. For tourmaline, a mineral with one of the most exquisite arrays of color, geologists tease apart the complex clues it harbors, and gemologists can use these to tell the story of each gemstone. The widespread occurrence of the tourmaline minerals and their ability to imprint, record, and retain information make them a valuable tool for investigating Earth’s geological processes. Tourmaline is the ultimate keeper of geologic information, a geologic DVD.
“Boehmite Needles” in Corundum Are Rose Channels
Franck Notari1, Emmanuel Fritsch2 (presenter), Candice Caplan1, and Thomas Hainschwang1
1GGTL-Laboratories Switzerland, Geneva, and Balzers, Liechtenstein
2Institut des Matériaux Jean Rouxel and University of Nantes, France
Crystallographically oriented, linear inclusions in corundum are often referred to as “boehmite needles” or “polycrystalline boehmite” (boehmite is the orthorhombic aluminum hydroxide g-AlOOH). These inclusions are oriented along the edges of the rhombohedral faces and form angles of about 90°. They are always found at the intersection of twin lamellae, formed by twinning along the rhombohedral faces. They contain apparently polycrystalline material tentatively identified (at least in some cases) as boehmite. These are common in natural corundum and sometimes used as a criterion to separate natural from synthetic corundum.
Boehmite can be recognized through its infrared absorption. The great majority of the “needle”-containing gem corundum showed no boehmite infrared absorption, thus leading us to believe that these inclusions have a different origin. Microscopic observation reveals three aspects: some are lath- or ribbon-shaped, others are clearly negative crystals, and sometimes they appear as dotted lines. At the outcrop of the feature on the gem’s surface there is most commonly a void that can be followed into the gem, so the “needle” is essentially empty. This feature was also documented in a flux-grown synthetic ruby with no boehmite infrared signal. These channels are favored during titanium diffusion and take on color first, as diffusion is much faster in the empty space.

Figure 1. Left: Rose channels at the intersection of twin lamellae in a 7.17 ct color-change sapphire from East Africa, viewed in partially polarized light. Right: Detail of the same zone in reflected light, illustrating the fact that these channels are empty. Photos by Franck Notari; fields of view approximately 5.66 mm (left) and 2.83 mm (right).
It is known that in a small number of materials—some metals, calcite, and diamond—hollow channels may form at the intersection of twin lamellae, caused by deformation twinning. This was discovered by Gustav Rose (1868) in calcite, and thus the features are called “Rose channels” (figure 1). We believe that “boehmite needles” are in fact Rose channels. Even when very small, these channels would explain the optical relief observed, without a change in chemistry or infrared absorption. They fit the crystallographic nature of the structures observed.
Gemstones and Photoluminescence
Claudio C. Milisenda
DSEF German Gem Lab, Idar-Oberstein
Laser- and ultraviolet-excited luminescence spectroscopy and imaging are important techniques for gemstone testing, as they are among the most sensitive spectroscopic methods (see Hainschwang et al., 2013). They are able to identify optically active crystallographic defects such as vacancies and substitutions that are present in such small amounts that they cannot be detected by any other analytical method. Photoluminescence (PL) analysis became particularly important in the last decade for the separation of natural from synthetic diamonds and the detection of treatments. Today the availability of specially designed and reasonably priced portable equipment enables the rapid in situ identification of mounted and unmounted natural diamonds.
Although PL spectroscopy is most commonly used for diamond identification, it can also be applied to colored stones. Some stones exhibit unique luminescence patterns, which can be used to identify the material. Other examples are the separation of natural from synthetic spinel and the detection of heat-treated spinel. Since chromium is a typical PL-causing trace element, it is also possible to separate chromium-colored gems such as ruby and jadeite from their artificially colored counterparts. The color authenticity of specific types of corals and pearls can also be determined.
The rare earth elements (REE) are among the main substituting luminescence centers in Ca2+-bearing minerals (Gaft et al., 2005). Recently, REE photoluminescence has been observed in cuprian liddicoatite tourmalines from Mozambique (Milisenda and Müller, 2017). When excited by a 785 nm laser, the stones showed a series of bands at 861, 869, 878, 894, and 1053 nm, consistent with the PL spectra of other calcium-rich minerals (Chen and Stimets, 2014). LA-ICP-MS analysis confirmed the REE enrichment in this type of tourmaline compared to cuprian elbaites from Brazil and Nigeria. As a result, photoluminescence can be used as a further criterion for origin determination of Paraíba-type tourmalines.
We have extended our research on other calcium-rich gems, including various grossular garnet varieties such as hessonite and tsavorite (figure 1), uvarovite garnet, apatite, titanite, and scheelite, as well as a number of high-refractive-index glasses and color-change glasses, respectively.

Figure 1. 785 nm laser-induced REE photoluminescence spectra of tsavorite and hessonite garnets. Spectra are offset for clarity.
REFERENCES
Chen H., Stimets R.W. (2014) Fluorescence of trivalent neodymium in various materials excited by a 785 nm laser. American Mineralogist, Vol. 99, No. 2-3, pp. 332–342, https://doi.org/10.2138/am.2014.4311

Gaft M., Reisfeld R., Panczer G. (2005) Modern Luminescence Spectroscopy of Minerals and Materials. 2nd edition, Springer, Heidelberg, Germany, 606 pp.

Hainschwang T., Karampelas S., Fritsch E., Notari F. (2013) Luminescence spectroscopy and microscopy applied to study gem materials: a case study of C centre containing diamonds. Mineralogy and Petrology, Vol. 107, No. 3, pp. 393–413, https://doi.org/10.1007/s00710-013-0273-7

Milisenda C.C., Müller S. (2017) REE photoluminescence in Paraíba type tourmaline from Mozambique. 35th International Gemmological Conference, Windhoek, Namibia, pp. 71–73.
An Overview of Asteriated Gems: From Common Star Sapphire to Rare Star Aquamarine to One-of-a-Kind Star Zircon
Martin P. Steinbach
Steinbach–Gems with a Star, Idar-Oberstein, Germany
Rays of angel’s hair in a star-like shape, beams of light hovering over the surface of a gem—gems with stars have fascinated people of all cultures, continents, and religions since ancient times.
Asteriated gems have been known for more than 2,000 years, starting with Periegetes’ description of “Asterios” in the first century BCE. Other historical names were asteria, asterius, astrion, astrodamas, and astriotes. From Pliny the Elder (first century CE) to the Middle Ages, to De Boodt (1609) and Brueckmann (1783), asterism was known only in corundum and some feldspar varieties.

Figure 1. This 15.51 ct star rhodochrosite is from the Sweet Home mine in the state of Colorado. Photo by Martin P. Steinbach.
Currently, about 60 different gem varieties display asterism, whereas 15 gemstone varieties show a “trapiche” star. The well-known commercial examples include star ruby, sapphire, quartz, almandine garnet, moonstone (orthoclase feldspar), and the four-rayed black star diopside from India. Rare or less well-known varieties include star aquamarine, beryl, bronzite, calcite, chrysoberyl (A.G.S. Research Service, 1937), enstatite, hypersthene, kyanite, peridot, scheelite, scapolite, spinel, and sunstone (oligoclase feldspar). The extremely rare one-of-a-kind stars consist of star alexandrite, amazonite (Steinbach, 2016), cordierite, apatite, “star diamond,” ekanite, emerald (Liddicoat, 1977), kornerupine, kunzite, labradorite, opal, parisite, prehnite, rhodochrosite (figure 1), rhodonite, rutile, serandite, fibrolite (sillimanite), spessartine, taaffeite, tanzanite, topaz, tourmaline, and zircon.
Some of the 60 different star stones introduced in this colorful presentation can also show double stars; 12-, 18-, or 24-rayed stars; a network of stars; and trapiche varieties.
One new source of star rose quartz (China) and two new sources of almandine star garnet (China and Russia) will also be presented.
REFERENCES
A.G.S. Research Service (1937) Star chrysoberyl. G&G, Vol. 2, No. 8, p. 130.

Liddicoat R.T. (1977) Comments on the Hixon Collection. G&G, Vol. 15, No. 9, p. 1.

Steinbach M.P. (2016) Asterism—Gems with a Star. MPS Publishing and Media, Idar-Oberstein, Germany, 896 pp.
Quantitative Identification of Green Nephrite from Five Major Origins In Asia and North America
Zemin Luo, Andy H. Shen, and Meihua Chen
China University of Geosciences, Wuhan
Green nephrite (serpentine-related) has been generating substantial interest in the gem market. The primary sources are China, Russia, and Canada. Preliminary observations of mineral impurities and chemical components can help separate some dolomite-related nephrite from serpentine-related material. We have developed a novel classifier that can automatically identify the geological origin of random green nephrite samples on the market with 95% prediction accuracy. The technique behind this classifier is based on a trace-element database for green nephrite and a machine learning algorithm.

Figure 1. Representative green nephrite samples from the five serpentine-related deposits in Asia and North America: Manasi (A), Hetian (B), Taiwan (C), British Columbia (D), and Siberia (E).
The green nephrite database was built from 34 samples from five major geological origins (Manasi and Hetian in Xinjiang, China; Taiwan; British Columbia, Canada; and Siberia, Russia; representative samples are shown in figure 1). Trace-element information was collected by LA-ICP-MS with an average of six points on each sample. The following classification models were tested: neural network (multilayer perceptron), random forest, logistic regression, naive Bayes, and support vector machine. The random forest model gives the best performance on both training sets and cross-validation sets, with over 90% accuracy (table 1). The random forest model also identified the 10 most important trace elements for green nephrite classification as Sr, Ba, Zn, U, Ti, LREE, Cd, Rb, Mn, and K (figure 2). The geological information about this trace-element “fingerprint” needs further investigation.

Figure 2. The 10 most important trace elements for green nephrite classification, ranked in descending order, analyzed by the random forest algorithm.

We used linear discriminant analysis (LDA) to visually demonstrate the obvious separation of Siberian and Manasi green nephrites from the other origins (figure 3). This result is consistent with our optic and spectra characterization results. Green nephrite from the Manasi mine usually presents a heterogeneous grayish yellow green color, which is quite different from that of other origins. The absence of garnet inclusions in Siberian green nephrite—which distinguishes it from material from the other localities—can be confirmed by Raman spectroscopy. Samples from all origins have been characterized by photomicrography, micro-infrared spectra, and Raman spectra. We can therefore integrate the spectra and trace-element features into our classification model in the next step. We believe that the research method proved in this work is also applicable for other gemstones. It can also be a useful tool to study ancient green nephrite origins.

Figure 3. This scatter plot illustrates how an LDA algorithm was used to separate green nephrite. It shows clear separation of Manasi and Siberian nephrite from the other three origins (Hetian, British Columbia, and Taiwan), which show obvious overlap.
Radiocarbon Measurements on Pearls: Principles, Complexities, and Possibilities
Gregory Hodgins
University of Arizona Accelerator Mass Spectrometry Laboratory, Tucson
Radiocarbon dating is a method for determining the age of organic remains formed in the past 45,000 years. Also known as carbon-14 or 14C (figure 1), radiocarbon is a naturally occurring radioactive isotope of carbon with a half-life of 5,730 years. It is continuously formed in the earth’s upper atmosphere and makes its way into the biosphere via photosynthetic uptake and the food chain. Several radiocarbon dates for pearls have recently appeared in the scientific literature. Mollusks take up radiocarbon during life and incorporate it into shell and pearl carbonate. The aim of this presentation will be to describe the method, identification complexities, and challenges inherent in dating pearls based upon radiocarbon measurement so that we may plot a path for future research.

Figure 1. The author stands beside the terminus of the accelerator mass spectrometer radiocarbon beam line. Photo by Gretchen Gibbs.
There are two variants of the dating method. The first is conventional radiocarbon dating, which applies to organisms that lived before 1955 CE. The second involves the detection of anthropogenic radiocarbon in organisms living between 1955 CE and the present. There are biological, environmental, and experimental complexities in the radiocarbon dating of pearls, and the method will not work in all circumstances. However, some of these complexities—coupled with historic changes in when, where, and how pearls have been produced—mean radiocarbon measurement can provide information unavailable by other means.
Unconventional Techniques in Pearl Testing: Their Potential and Limitations
Chunhui Zhou
GIA, New York
Current routine pearl testing involves the application of various basic and advanced gemological techniques. These include the use of the gemological microscope, ultraviolet (UV) luminescence, microradiography, computed X-ray microtomography, optical X-ray luminescence, energy-dispersive X-ray fluorescence spectrometry (EDXRF), ultraviolet-visible (UV-Vis) spectroscopy, and Raman spectroscopy. While the majority of pearls may be identified using these existing conventional techniques, in certain cases identification challenges remain.

Figure 1. The application of unconventional pearl testing methods could be useful in separating difficult pearl samples, such as various types of freshwater pearls shown here. Photo by Diego Sanchez.
This talk will discuss the potential and limitations of various unconventional techniques that have been applied to pearl testing over recent years. Some of these techniques have been explored by GIA and resulted in meaningful benefits to the trade, and others referenced in the literature will also be briefly covered. Examples of these techniques include radiocarbon age dating, deoxyribonucleic acid (DNA) bar coding, in-depth trace-element geochemistry and isotope analysis, and 3D reconstruction of internal structures. It is important for gemological and research institutions to continue developing novel techniques for pearl testing in order to achieve the accurate separation between natural and cultured pearls, principally non-bead cultured, as well as other aspects of identification that might assist in reaching this accurate analysis (e.g., species determination, geographical origin determination, and treatment identification). Despite decades of pearl testing experience, some challenges remain within laboratories, and the application of additional unconventional methods could resolve some of these issues.
ADDITIONAL READING
Krzemnicki M.S., Hajdas I. (2013) Age determination of pearls: A new approach for pearl testing and identification. Radiocarbon, Vol. 55, No. 3, pp. 1801–1809, http://dx.doi.org/10.1017/S0033822200048700

Meyer J.B., Cartier L.E., Pinto-Figueroa E.A., Krzemnicki M.S., Hänni H.A., McDonald B.A. (2013) DNA fingerprinting of pearls to determine their origins. PLOS One, Vol. 8, No. 10, pp. 1–11, http://dx.doi.org/10.1371/journal.pone.0075606

Saruwatari K., Suzuki M., Zhou C., Kessrapong P., Sturman N. (2018) DNA techniques applied to the identification of Pinctada fucata pearls from Uwajima, Ehime Prefecture, Japan. G&G, Vol. 54, No. 1, pp. 40–50, http://dx.doi.org/10.5741/GEMS.54.1.40

Zhou C., Hodgins G., Lange T., Saruwatari K., Sturman N., Kiefert L., Schollenbruch K. (2017) Saltwater pearls from the pre- to early Columbian era: A gemological and radiocarbon dating study. G&G, Vol. 53, No. 3, pp. 286–295, http://dx.doi.org/10.5741/GEMS.53.3.286
What Is Cobalt Spinel? Unraveling the Causes of Color in Blue Spinels
Aaron C. Palke and Ziyin Sun
GIA, Carlsbad, California
Cobalt is known to produce vibrant blue color in both natural and synthetic spinel. In the 1980s and ’90s, Vietnam started producing blue spinel with very high concentrations of cobalt and bright, saturated color rivaling that seen in synthetic material. Iron can also cause blue coloration in spinel, although this is typically a duller grayish or greenish blue. So when is a blue spinel worthy of carrying the “cobalt spinel” moniker? With high-sensitivity analytical methods such as LA-ICP-MS, cobalt can be detected in most spinel, even at the sub-ppm level. But sub-ppm concentrations of cobalt do not impact the color of a faceted spinel. In addition, the saturation and quality of blue color will depend on the concentration of iron and its valence state (e.g., Fe2+ vs. Fe3+).
In this contribution we will explore the color space of blue spinel and outline the various contributions to their coloration. Using UV-Vis spectrometry and LA-ICP-MS on blue spinel from Vietnam, Sri Lanka, Madagascar, and Tanzania, we have isolated three unique and consistent chromophores (see figure 1). Cobalt in its divalent form (Co2+) has multiple absorption bands between ~510 and 660 nm and produces a bright blue color. Two broad absorption bands at ~650 and 920 nm are related to Fe2+ substituting for Al3+ in octahedral coordination. Finally, another set of at least three absorption bands occurs at ~500–620 nm and overlaps those from Co2+. Comparison with other Fe-related absorption bands and consideration of the crystal chemistry of spinel suggest that these bands may be related to Fe3+ in the tetrahedral site in the spinel structure. This last absorption feature creates a grayish pink coloration, and in combination with Co2+ it can be responsible for blue to violet color change in some spinel. There is clearly a significant interplay between these three chromophores, and a full understanding of the causes of color in blue spinel can only be attained by consideration of all three contributions.

Figure 1. UV-Vis spectra of the individual contributions from three chromophores in blue spinel, octahedral ferrous iron (VIFe2+), octahedral cobalt (VICo2+), and tetrahedral ferric iron (IVFe3+). At the top is the full spectrum of a blue spinel from Tanzania, followed by the sum of the three individual components (SUM). UV-Vis spectra of all blue spinels in this study could be recreated with varying contributions from the three spectra at the bottom. @chapter:0 @chapter:0 @chapter:0


# Publication Year: 2021
# Title: Unusual Fibrous Inclusions in Blue Opal
# Abstract: These unusual clusters of curled fibers were seen in a blue opal. Photomicrograph by Nathan Renfro; field of view 3.58 mm

The authors recently encountered an opal with a grayish blue bodycolor and weak play-of-color. The gem also contained some interesting fibrous inclusions (see above). The inclusions were generally scattered throughout a planar zone as curled bundles of chatoyant fibers. This type of opal appeared to be naturally colored and consistent in appearance and physical properties with opal from Sinaloa, Mexico (Fall 2011 Gem News International, p. 243). Raman analysis was unable to identify the inclusions, but a strong cristobalite signal was measured in areas with the fibers and without them, suggesting a volcanic origin (E. Fritsch et al., “Green-luminescing hyalite opal from Zacatecas, Mexico,” Journal of Gemmology, Vol. 34, No. 6, 2015, pp. 490–508). While the exact nature of these inclusions remains a mystery, this is the first time the authors have encountered this type of unusual coiled fibrous inclusion in blue opal. @chapter:48 @chapter:0 @chapter:48


# Publication Year: 2013
# Title: Pseudo-Synthetic Growth Structure Observed in Natural Diamond
# Abstract: Figure 1. This 0.70 ct, D-color natural round brilliant displayed the cuboctahedral growth structure of an HPHT-grown synthetic diamond. Photo by Jian Xin(Jae) Liao.

Synthetic diamonds created using the traditional HPHT (high-pressure, high-temperature) process ordinarily grow as cuboctahedra. Temperature dictates the crystal form, as cubic growth is predominant at the relatively low temperatures of synthesis. At the higher temperatures of natural formation environments, diamonds typically grow as octahedrons. While small cuboctahedral diamonds are found in nature, these are very rare.
Recently submitted to the GIA laboratory in Israel was a near-colorless 0.70 ct round brilliant (figure 1). Found to be a type IIa diamond with no detectable nitrogen impurity, it was examined further for possible treatments and to verify the origin of color.

Figure 2. DiamondView imaging of the pavilion facets revealed a subtle growth structure. The inset shows the growth structure of a type IIb synthetic diamond. Photo by Wuyi Wang.
In the short-wave UV radiation of the DiamondView, a subtle cuboctahedral growth structure (figure 2) was observed on the pavilion facets. This type of structure usually indicates an HPHT-grown synthetic diamond.
The diamond possessed D color and high clarity, with no internal inclusions to help indicate whether it was in fact natural. Shallow surface-reaching fractures were observed, and a few extra facets close to the pavilion contained these natural-looking fractures.
Microscopic observation with cross-polarized light showed relatively strong tatami strain pattern (figure 3), a feature indicative of natural growth. Further examination at higher magnification revealed small polygonal dislocation networks on the pavilion. These provided conclusive evidence that the stone was a natural diamond crystal (figure 4).

Figure 3. A tatami strain pattern, observed under crossed-polarized light, indicated natural growth. Magnified 40×. Photo by Paul Johnson.

Figure 4. DiamondView imaging showed a micro-dislocation network on pavilion facets, conclusive proof of natural crystal growth. Photo by Wuyi Wang.
This stone was a good example of a very rare natural diamond exhibiting synthetic growth characteristics. It exemplifies the challenges posed to gemological laboratories in separating natural from undisclosed gem-quality synthetic diamonds in today’s jewelry market. We concluded that the diamond had a natural color origin. @chapter:9 @chapter:1 @chapter:9


# Publication Year: -
# Title: Lapis Lazuli Care and Cleaning
# Abstract: With proper care, lapis lazuli can provide a lifetime of jewelry-wearing enjoyment. - Dr. Edward J. Gübelin

                      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.

Lapis is between 5 and 6 on the Mohs scale, depending on its composition. With care, lapis jewelry and carvings can delight their owners for generations. Its toughness is considered Fair.

	Lapis lazuli’s hardness ranks between 5 and 6 on the Mohs hardness scale.

Stability
The dye used in some lapis can come off if it’s rubbed with acetone (nail polish remover) or denatured alcohol, so it’s sometimes sealed with wax or plastic. Wax sealers can deteriorate when they’re exposed to heat or solvents.

Lapis that hasn’t been dyed might be impregnated with wax or oil to improve its color and luster. These treatments have only fair stability, and a gemologist can detect them.

Cleaning
Warm, soapy water is the safest way to clean lapis lazuli. It’s best to test a small, inconspicuous area first, because some dye treatments are not stable. @chapter:27 @chapter:1 @chapter:27


# Publication Year: 2014
# Title: Innovative Optical Effects, Unique Rings with Raw Crystals – Tucson 2014
# Abstract: "Wheels of light" are innovative quartz disks with sealed inserts of colored gems or minerals, creating multiple reflections to lend color to otherwise transparent rock crystal. Inside these examples are Paraíba tourmaline (left) and realgar (right). Photos by Eric Welch; courtesy of Nature’s Geometry.

              At GJX, Brian and Kendra Cook (Nature’s Geometry, Graton, California) showed an innovative series of clear quartz disks they call “wheels of light.” These disks are mounted in work-hardened 24K yellow gold for use as pendants or earrings. The center of each disk contains a tube where an insert of colored gem material can be placed. The tube is subsequently sealed with clear quartz. When the disk is viewed face up, the insert’s color reflects and suffuses the disk with bright color (figure 1).

	Brian and Kendra CookNature's Geometry

Husband-and-wife team Brian and Kendra Cook reveal the design philosophy behind their unique gemstone products, which use ‘raw’ gem crystals, clever optical effects, or carry aromatic oils in tiny wells to tantalize the senses in a combination of texture, color, and scent.
For red, Brian Cook uses ruby or even realgar (also known as “ruby sulfur,” a very soft arsenic sulfide mineral), and Paraíba tourmaline or haüyne (a brittle sodium calcium sulfate) for rich blues. As the insert is completely enclosed within the quartz, the materials are protected from wear.

	Figure 2. This ring’s centerpiece is a euhedral 2.76 ct ruby crystal from Winza, Tanzania, flanked by a pair of Canadian rough diamonds. Two green diamonds from Venezuela complete the piece. Photo by Eric Welch; courtesy of Nature’s Geometry.

	Figure 3. This ring features cat’s-eye spessartine garnet with Paraíba tourmaline shoulder stones in a 24K work-hardened gold mounting. Photo by Eric Welch; courtesy of Nature’s Geometry.
Brian Cook displayed several intriguing rings with rough crystals, including ruby (figure 2), alexandrite, and diamond, also in work-hardened gold. Another standout featured a cat’s-eye spessartine garnet with Paraíba tourmaline cabochons in a similar mounting (figure 3).

In the accompanying video, Kendra Cook answers the rhetorical question, “What could be better than jewelry that affects your emotions pleasantly?” with her innovative aroma jewels. She places essential oils that calm or energize the wearer within tiny wells in gemstones that are left open to evaporation. She also coordinates color with scent, using warm scents for gems like sunstone and cool scents for gems like aquamarine.

The result is “a mélange of color,” a combination of design, gem crystals, and color that work in synergy with aromatherapy like a wearable potpourri. Brian Cook helps source for unusual gem crystals, such as a clear oligoclase, for fashioning into sliding gem beads where essential oils nestle to comfort and revive the wearer. @chapter:17 @chapter:0 @chapter:17


# Publication Year: -
# Title: Alumni Members: Stand Out by Taking Advantage of Opportunities, Events
# Abstract: Cincinnati chapter members gathered to learn about advancements in jewelry manufacturing from specialist and guest speaker Chris Glazer, who featured a review of 3-D scanning technology. Courtesy of the Cincinnati Chapter.

Summer time and the living is easy … at least for our alumni worldwide, because in my opinion, we work in the greatest industry in the world. When you have a passion for what you do, it simply is not work. You see this in industry members and alumni who light up when they begin to talk about what they do.

To quote E.M. Foster: “One person with passion is better than forty people merely interested.”

I love this quote and can think of an extensive list of names of people in our industry whose passion proceeds them. They are industry beacons who draw us to them and inspire us with their drive to increase their expertise and knowledge and their reflection of integrity. The most remarkable thing about these people is that they measure or value their personal success by their ability to share their knowledge, act as mentors and provide service to the industry they love.

Some of these folks may be in our personal contact list and some may be on our get-to-know wish list. I suggest you put yourself out there and try to meet these beacons of the industry. Go to shows and approach an expert if you have questions, attend alumni events where industry leaders speak or attend, commit to continued learning by attending lectures and conferences. Each of these steps will help you grow your personal network of contacts and become that alumnus who stands out.

Be a person with passion. Leverage the interests that brought us all to this inspiring industry. Whether you are just starting out, in the twilight of your career, or somewhere in between, the connection we all have to GIA as alumni members and lifetime students bring us together with shared passion for an education and excellence. This is the foundation of the GIA Alumni Association.

I have highlighted alumni events below that have occurred since our last report in May and those that are on the horizon. Each activity is an opportunity to align yourself with others who share our passion for our industry. Please note the topics, speakers and locations of alumni activities that occur across the globe and take advantage of these opportunities.

Alumni chapter and GIA-hosted events are available for you to invest in yourself and become a GIA Alumni member who stands out.

Global tradeshows provide the opportunity for alumni chapter leaders to connect with GIA in person. Above, Rong Julius Zheng, president of Shanghai chapter, left, and Kate Donovan, GIA Global Alumni Relations Manager, with a cardboard cutout of Richard T. Liddicoat on display in celebration of the centennial year of his birth at the JCK Las Vegas show. Photo courtesy of Rong Julius Zheng.
GIA Hosted Opportunities

108th Gemstone Gathering – A lecture series organized by GIA Bangkok, featured “A Brief History of Colored Gemstone Faceting,” by Justin K Prim, gem cutter, author and lapidary instructor. Find out more details  on this event and future events.
GIA Alumni at JCK Las Vegas – The largest gem, jewelry and watch fair in the U.S brings more than 30,000 people together for commerce and comradery. The GIA Alumni Association and our members participated in a number of social events, including the Red Square Meet-Up and the Rocks the Bowl Party, and met up regularly at the GIA booth. Each of these were wonderful opportunities for our global alumni to connect as attendees and vendors and brought alumni members and industry friends from across the globe together.
GIA Career Fair New York – Provided a day of opportunity to all who attended and participated in July. From a dynamic opening panel of speakers and one-on-one recruiting and career coaching, this annual GIA event delivers a platform for the Institute’s student and graduates, industry leaders and the public to converge. This event helps ensure the success of our industry and its future. GIA has hosted GIA Career Fair for more than 25 years in New York and in California, and held the first-ever in Career Fair in London earlier this year. Visit the Career Fair website for more details.
GIA Advanced Synthetic Diamond Seminar – The first series of this new training program was held in Hong Kong in June and upcoming seminars will be held in Mumbai, London and Carlsbad. Read more in the press release.

GIA’s commitment to support our alumni chapters and members
Delivering a promise from GIA to expand benefits and grow support for our alumni network worldwide, the Institute arranged GIA speakers at seven global alumni chapter events since May:

Dr. Wuyi Wang, vice president of research and development, offered insight on laboratory developments, research conducted on synthetic diamonds, and the latest gem testing devices and screening services offered by GIA, in Macau and Taiwan.
Dr. James Shigley, Distinguished Research Fellow at GIA, and Brenda Harwick, GIA GG and senior manager of on campus instruction, delivered a synthetic diamond update and hands-on session, in Ohio.
Andy Lucas provided a GIA field gemology update and discussed recent expeditions to Greenland ruby mines and Ethiopia sapphire mines to alumni in San Diego and members of American Society of Appraisers (ASA) who were visiting GIA’s Carlsbad campus for an education opportunity.
Shelly Verwymeren, GIA GG and instructor, provided a synthetic diamond lecture and the opportunity to view natural diamond and samples of HPHT and CVD grown synthetic diamonds, in Wisconsin.
Crystal Nel and Elizabeth Bokaba, from GIA’s Africa staff, presented GIA Gemkids and shared tools available from GIA to step up your marketing game, to alumni in Tanzania.
Three members of the GIA Laboratory Gem Identification Department – Daniel Girma, Tyler Smith and Jessica Jasso – provided a lab update for Manhattan.

London alumni chapter leaders Lubica Micatkova, treasurer, (left), Sharon Dale, president, (second from left) and Eloise Mathieu, secretary (right) pose with Sarah Hue-Williams, guest lecturer (second from right) at the end of another successful London alumni chapter event. Photo courtesy of the London Chapter.

Recognizing Longtime GIA Alumni Leaders for Commitment and Giving Back as Mentors
The benefits of involving yourself in GIA Alumni activities or within your chapter as a leader, or otherwise, is immeasurable and it is FUN. Just ask any of the following volunteer alumni leaders. From life-long friendships, expanding business opportunities and staying relevant with up-to-date education in today’s marketplace, there’s a reason why these exceptional alumni leaders have remained actively involved with the GIA Alumni Association for more than 25 years – and continue to do so today.

Here are some former and present chapter leaders who provide valuable knowledge as presenters at our chapters:

Sindi Schloss (former president and residing president of the Metro-Phoenix Chapter) shared insight on “Estate Exotics” and the opportunity to find and appreciate the bead and gemstone necklace treasures of the past, in San Diego.
Richard Drucker (former president of the Chicago Chapter) delivered a colored gemstone pricing and treatment overview in Manhattan.
Suzanne Martinez and Starla Turner (former co-presidents and founding members of the Golden Gate Chapter) provided a historical review of diamond ring styles to Golden Gate, California.
Bill Korst (former chapter president and board member of the Michigan Chapter) presented “All About Garnets” at a gem study group and barbeque, in Michigan.
Note: many additional alumni leaders should be recognized here – their exclusion is simply because we are reporting on activities in the last three months – but we are no less appreciative for all of the folks who regularly serve as mentors, educators and volunteers in their chapters. To each of them, we thank you.

GIA Alumni Switzerland chapter members enjoy an interactive refresher of gemological equipment use by presenter Guillaume Chautru, head of the gemology department at Piaget SA. Photo courtesy of the Switzerland Chapter.
Here is a list of additional chapter news and events that have occurred since our last AlumConnect issue, in May.

Social Gatherings brought Hong Kong, Houston, Louisiana, Mumbai, South Carolina and Toronto alumni, students and industry friends together for networking fun, as well as for the celebration of Monterrey-Mexico chapter’s third anniversary.
Hands-on Instruments Workshop by Guillaume Chautru, head of the Gemology Department at Piaget SA, led a fun, hands-on refresher on tips to make an expert assessment (as a gemologist) with the use of classical gemological instruments, to members in Switzerland.
Gemology Tours and Excursions included an annual Gemstone Safari visit to Mexico’s Sea of Cortez, for the pearl harvest by members of Mexico City, and a field trip to the Heard Museum to view a retrospective collection of one of the Southwest’s most noted jewelry designers Richard Chavez’s 40-year career by Metro-Phoenix.
Twenty-First Century Jade was the featured presentation by author, gemologist and lecturer Renee Newman, GIA GG, in Washington, D.C.
Lab Grown (Synthetic) Diamonds: Products, Perception and Reality was presented by Stanley Zale, VP of Diamonds & Gemstone Procurement, Stuller, Inc. to a full house, in New England.
Jewelry History topics featured notable speakers in multiple chapters. Jason Adams discussed the history, identification and evaluation of jewelry from 17th to the 20th century, to an attentive audience in Ohio.  Lauren Abramowitz, GIA GG shared “With Tiffany Blue, What Rings True?” an in-depth presentation on how to recognize legitimate Tiffany jewelry and products from the mass produced and custom-made imitations found in the marketplace globally, with members of Twin Cities, in Minnesota.
Advancements in Jewelry Manufacturing was presented by manufacturing specialist Chris Glazer, and featured a review of 3-D scanning technology, in Cincinnati.
Expanding Service and Improving Profits by understanding and providing services to re-polish and/or re-cut diamonds and colored stones to add value to your client’s stone or your company’s inventory, was a well-received topic in Michigan.
An evening with Sarah Hue-Williams, noted historian, author, gemologist and lecturer, shared insight and stories surrounding the sales of some of the jewelry that has passed through Christie's salerooms around the world and her involvement in extensive research for some of the most significant jewelry auctions of recent years, enthralling attendees in London.

Upcoming GIA Education and Networking Opportunities
Mark your calendars for these upcoming events and valuable education and networking opportunities:

GIA Symposium in 2018 – The date is quickly approaching for this extraordinary gathering of gemstone and jewelry professionals. Current registrations include representatives from 38 countries from across the globe and we hope you consider joining. Do not miss the sixth ever symposium in GIA’s history, and the opportunity to participate in this historical event. Registration is available for the GIA International Gemological Symposium, to be hosted in Carlsbad, California from Oct. 7-9, 2018. Visit the event website for an outline of symposium experience and offerings.
Tucson 2019 – Party at the GIA Gem Mine: India Odyssey: The date and the theme is set and the GIA team is actively planning the Alumni Association’s biggest event each year. Please mark your calendar to join us on Friday, Feb. 8, 2019, for this annual gathering that brings alumni and industry friends together from across the globe. The night includes dinner, dancing and silent and live auctions and all proceeds benefit the Alumni Endowment Fund to support alumni benefits and programs worldwide. Visit the party web page to learn more.

I hope this overview of alumni activities has inspired you to get involved and benefit from the relationships and opportunities available through the GIA Alumni Association. As a global community, opportunity and education is there for you both digitally and in person, you simply need to make the effort to invest in yourself. @chapter:45 @chapter:3 @chapter:45


# Publication Year: 2023
# Title: Pink Zektzerite
# Abstract: An exceptional pink zektzerite, cut as a square modified step cut, measuring 8.08 × 7.39 × 6.89 mm and weighing 2.95 ct. Photo by Diego Sanchez.
Zektzerite, a member of the tuhualite group, is a very rare collectible mineral currently mined from only two sources: Okanogan County in the U.S. state of Washington (Spring 2011 Gem News International, p. 61), and the Darai-Pioz Valley in Tajikistan (L.A. Pautovet et al., “Zektzerite—occurrence in Tadzhikistan,” Mineralogicheskii Zhurnal, Vol. 14, pp.  75–78). With the chemical formula NaLiZrSi6O15, these rare crystals are found in miarolitic cavities in riebeckite granite, along with many other rare minerals. The zektzerite crystals found in these locations are primarily between 4 mm and 15 mm and usually yield small faceted gems weighing less than 2 ct. This material is typically found with a low transparency and muted color saturations. Perfect cleavage in two directions and a brittle tendency make this fragile stone very difficult and risky to cut. Due to its low durability and overall dull appearance, collectors tend to leave zektzerite in its natural rough state.
An outstanding example of faceted gem-quality zektzerite (see above) was recently submitted to GIA’s Carlsbad laboratory. The stone weighed 2.95 ct, measured 8.08 × 7.39 × 6.89 mm, and had a refractive index ranging between 1.578 and 1.584. A specific gravity of 2.81, along with Raman and infrared spectroscopic testing, all matched zektzerite, with no indication of dye or polymers. The outstanding pink color, relatively high clarity, and impressive size of this stone sets this specimen far above any other faceted zektzerite previously reported. @chapter:3 @chapter:0 @chapter:3


# Publication Year: 1995
# Title: Sapphires from Southern Vietnam
# Abstract: Gem-quality blue to bluish green sapphires from basaltic terrains in southern provinces of Vietnam have been entering the gemstone market since the late 1980s.Visits to two of the sapphire-producing areas—Phan Thiet and Di Linh—confirmed that the sapphires occur in association with alkali basalts. Mining was done by hand at the Phan Thiet localities and with relatively sophisticated equipment at Di Linh. Investigation of 250 faceted samples revealed gemological, spectroscopic, and chemical properties similar to those of other basaltic sapphires. Notable internal features are prominent growth structures, distinctive color zoning, various crosshatch to lath-like "cloud" patterns, and several mineral inclusions. @chapter:0 @chapter:0 @chapter:0


# Publication Year: -
# Title: Inside De Beers’ Lightbox Diamonds
# Abstract: GIA research scientist Dr. Sally Eaton-Magana analyzes the image of a marquise diamond in the DiamondView to determine whether or not the stone is synthetic. Photo by Russell Shor/GIA

De Beers’ line of laboratory-grown diamonds, Lightbox, made its retail debut in the fall. Shortly afterward, GIA researcher, Dr. Sally Eaton-Magana, who has been identifying and analyzing lab-grown diamonds for 11 years, took a close look at the new De Beers-produced product for the Winter 2018 issue of Gems & Gemology.

Lightbox diamonds are produced in quarter carat, half carat and full carat sizes in colorless, pink and blue, and are uniformly priced at $800 per carat. Eaton-Magana examined two colorless specimens of .24 ct and .26 ct, respectively.

Both stones had color equivalent to G on the GIA diamond color scale, with cut grades of excellent and very good. Both were very high clarity, the equivalent of VVS2 on the GIA clarity scale. The smaller diamond had a pinpoint in a bezel facet, while the other had a tiny feather in a star facet. The laser-inscribed Lightbox logo (2 equilateral triangles base to base with an isosceles triangle in the middle) under the table – large enough to be easily visible with a microscope – would reduce the equivalent clarity grade to VS2. GIA Synthetic Diamond Grading Reports use ranges, rather than specific grades, to describe the color and clarity of laboratory-grown diamonds.

Magana confirmed that the Lightbox diamonds were grown using the chemical vapor deposition (CVD) process, which means they are Type IIa with no detectable nitrogen. “The identification criteria for high pressure, high temperature (HPHT) and CVD synthetics can be quite distinct from each other,” she explained, adding that synthetic products have become much more varied over the last 10-15 years.

“When the GIA synthetic diamond grading report was first launched in 2007, CVD synthetics were not commercially available,” she noted. “The commercially available sizes of lab-grown diamonds have expanded such that both very large and very small stones are possible. Also, colorless to near-colorless synthetics were once quite rare and are now the majority seen at the lab.”

Although Lightbox is new to the market, and the variety of lab grown diamonds is increasing, the fundamental identification criteria have not changed. They are based on growth morphology and optical properties. “We also regularly conduct research on emerging products and GIA has a program to grow synthetics ourselves to stay ahead of any new trends,” she said.

Similarly, the basic equipment for identification has not changed. Researchers and grading laboratory staff continue to rely on microscopy, fluorescence imaging, absorption spectroscopy, and photoluminescence (PL) spectroscopy. What has evolved, she said, is the speed and efficiency of these devices.

The evolution of PL mapping capabilities is important, she explained, because it enables GIA to collect thousands of spectra at micron-sized intervals across the surface of a diamond in mere minutes.

“This technology allows us to map the defect concentrations of synthetic diamond to visualize the growth sectors in HPHT synthetics,” Eaton-Magana explained. “The recent ability to collect many thousands of PL spectra instead of just one spectrum on a diamond gives us opportunities to draw correlations that would not have been previously possible. We have also expanded our research into largely previously unexplored variables – such as what are the effects on spectra within the diamond at various temperatures and timescales; for example, exploring diamond’s luminescence at the nanosecond to millisecond time ranges.”

She said that PL spectra showed the Lightbox diamonds were not subjected to post-growth HPHT processing to improve their color. The researchers noted that about 75% of all CVD-grown diamonds they encounter have been subjected to such treatment. This is because quite often these diamonds are grown with a brownish color, especially if the manufacturers attempt to grow them quickly. While the HPHT treatment process is effective in improving the color of CVD diamonds, the large amount of energy used to create sufficient heat and pressure can add significantly to the cost of production. The Lightbox products, however, are priced much lower than most other lab-grown diamonds in the market.

Both diamonds showed visible red fluorescence in imaging by the DiamondView synthetic detector, but had no detectable fluorescence under long wave UV light. The lab-grown diamonds did show tell-tale CVD growth striations, but they were difficult to spot, requiring careful DiamondView imaging.

Lightbox lab-grown diamonds are readily identifiable as CVD by spectroscopic techniques, DiamondView imaging and, of course, the inscribed logo under the table, her article noted.

Magana earned her doctoral degree in chemical engineering with Dr. John Angus, one of the early pioneers of CVD synthetic diamond growth. For her Ph.D. and post-doctoral work, she worked mainly on growing CVD synthetics for engineering and semiconductor applications.

“While at my post-doc assignment, we collaborated with the Smithsonian Institution to study the phosphorescence of type IIb diamonds in their collection, including the Hope Diamond. With this introduction to gem diamonds, I wanted to transition into this field and was fortunate to obtain a position at GIA following my post-doctoral assignment,” Magana said. “Since then, I have spent much of my time delving into the physics of gem diamonds, concentrating on various treatments, detection methods, and distinguishing synthetics from their natural counterparts.” @chapter:41 @chapter:1 @chapter:41


# Publication Year: 2016
# Title: Garnet Inclusion Illusion
# Abstract: Figure 1. At first glance, this 42.88 ct quartz double cabochon measuring 28 × 18.5 × 15 mm resembles a beautiful garnet-included quartz gem. Photo by Elise A. Skalwold, from the Si and Ann Frazier Collection.

	A cleverly designed “garnet in quartz” double cabochon represents a new and unexpected challenge for gemologists, collectors, and designers who intend to feature inclusion gemstones in their jewelry lines. This assembled inclusion consists of a fragment of pyralspite-series garnet sandwiched between two quartz cabochons (figure 1). The garnet and quartz were identified with optical and Raman spectroscopy, respectively, at GIA’s Carlsbad laboratory. While the specimen creates the illusion of being natural, clues to its artificial origin include air bubbles and the fragment itself, which shows neither crystal faces nor the rounded appearance of an etched or eroded crystal. Rather, it is a relatively sharp fragment that resides in a pocket filled with glue (figure 2). The subtle glue layer between the cabochons becomes more apparent when viewed under UV light, which causes it to fluoresce chalky white; this fluorescence is stronger under long-wave than short-wave UV.

Figure 2. Gas bubbles can be seen in an otherwise nearly invisible glue layer between the quartz cabochons; these bubbles are abundant in the vicinity of the red garnet fragment. The fragment resides in a hollowed-out pocket and is surrounded with glue. Photomicrograph by Nathan Renfro; field of view 10.28 mm.

	This specimen was purchased at the 2016 Tucson shows from a dealer specializing in inclusion specimens. The cabochon, part a collection of otherwise natural items, was fully disclosed as a man-made novelty. Its appearance in the marketplace represents an emerging trend that gemologists and collectors will see with increasing regularity as the fascination with inclusions grows (see the author’s forthcoming article, “Evolution of the inclusion illusion,” in the Summer 2016 InColor). Careful inspection with a loupe or microscope will in most cases reveal the underlying nature of this inclusion. @chapter:26 @chapter:0 @chapter:26


# Publication Year: 1996
# Title: Sapphires from the Andranondambo Region, Madagascar
# Abstract: Since 1993, large amounts of gem-quality sapphires from the Andranondambo region of southern Madagascar have entered the international gem market. These sapphires, which are found in metamorphic skarn-type deposits, show a broad range of gemological and chemical properties, many of which are similar to those of sapphires from Sri Lanka, Myanmar (Burma), and even Kashmir. Most of the Andranondambo sapphires are heat treated in Bangkok; these can be separated from their non-heat-treated counterparts on the basis of inclusion features and absorption spectra. Key factors in the separation of Andranondambo sapphires from synthetic sapphires of different manufacturers are chemistry (especially the Ga content of the natural material) and internal features. @chapter:14 @chapter:0 @chapter:14


# Publication Year: 2020
# Title: Elongated Rutile Crystal in Blue Sapphire from Afghanistan
# Abstract: The elongated orange transparent rutile crystal observed in the faceted blue sapphire from Afghanistan. Photomicrograph by Nattida Ng-Pooresatien; field of view 3.0 mm.
Rutile, titanium dioxide (TiO2), is a tetragonal mineral that generally occurs in corundum as silk (exsolution-formed needles), dust-like exsolution particles, or macroscopic crystal inclusions. Rutile crystals can have orange to deep red-brown coloration, and the crystal shapes can be rounded or euhedral.
The author recently examined a 4.24 ct faceted transparent blue sapphire from Afghanistan. The stone contained dusty flake-like inclusions, naturally healed fractures, lathe-like inclusions, twinning, rounded colorless crystals identified as apatite (RRUFF R040098), and an unusual long prismatic orange crystal identified as rutile (RRUFF R040049). This rutile crystal shape (see above) is not typical for corundum, particularly in blue sapphire. @chapter:26 @chapter:0 @chapter:26


# Publication Year: 2017
# Title: Natural Freshwater “Fish” Pearl
# Abstract: Figure 1. A 2.12 ct natural freshwater pearl with the form of a fish. Photo by Sood Oil (Judy) Chia.

The increased availability of freshwater cultured pearls in the market has brought their natural counterparts to the attention of collectors and the trade. Most natural freshwater pearls have been obtained from European waters and in the United States from rivers in the Mississippi Valley. A natural pearl occurs without human intervention and takes on the characteristic color and surface properties of the mollusk in which it forms. Freshwater pearls, whether cultured or natural, are attractive due to a wide variety of distinctive shapes, hues, and overtones. The New York lab recently examined a unique fish-shaped brownish orange pearl measuring 21.34 × 6.28 × 2.81 mm and weighing 2.12 ct (figure 1).

The entire nacreous surface was composed of overlapping platelets. We observed no indications of work, such as polishing, that is sometimes performed to improve a pearl’s appearance. One end was wider and more rounded, which bore an uncanny likeness to a fish’s head, with an “eye” and “mouth” also discernible. The lustrous orient along the body narrowed to a rounded point, resembling iridescent fish scales on a tail. Natural pearls are often baroque, and American freshwater pearls in particular are often found as elongated “wing” pearls (J.L. Sweaney and J.R. Latendresse, “Freshwater pearls of North America,” Fall 1984 G&G, pp. 125–140). Energy-dispersive X-ray fluorescence (EDXRF) chemical analysis and observation of X-ray fluorescence showed higher levels of manganese, proving that the pearl formed in a freshwater mussel. No indications of treatment such as dyeing or coating were detected under magnification or using advanced analytical procedures. Real-time microradiography and X-ray computed microtomography (µ-CT) analysis revealed clear natural growth structures that conformed to the pearl’s shape. 3D rendering of the µ-CT data (figure 2) showed a remarkable likeness to a small fish swimming.

Figure 2. 3D software rendering of X-ray µ-CT data revealed the pearl’s uncanny likeness to a fish. Images by Emiko Yazawa.
Although this is not the first pearl GIA has examined that bears a resemblance to a living creature (see Fall 2015 Lab Notes, pp. 319–320), it is nonetheless an extraordinary and rare formation that mirrors the form of a fish in surprising detail. @chapter:11 @chapter:4 @chapter:11


# Publication Year: -
# Title: GIA's Gübelin Gem Project: Various Gems, Amblygonite - Axinite
# Abstract: Apatite
Photo by Robert Weldon/GIA, courtesy Dr. E. J. Gübelin Collection
GIA Collection 33765

Among the collection assembled by Dr. Edward Gübelin are a number of uncommon gemstones from many worldwide localities. Documents, like the ones below, present information on gemstones that range from occasional use in jewelry to those that are quite rare and seldom faceted because of the lack of suitable starting material.

34543

			5.92 ct Amblygonite
			Myanmar (PDF)

33908

			4.85 ct Amblygonite
			Locality not stated (PDF)

33905

			12.18 ct Amblygonite
			Locality not stated (PDF)

34539

			17.86 ct Amphibole (Actinolite)
			Myanmar (PDF)

34990

			5.44 ct Amphibole (Actinolite)
			Tanzania (PDF)

34974

			13.66 ct Amphibole (Actinolite) -
			Nephrite
			Switzerland (PDF)

35409

			2.60 ct Amphibole (Hornblende)
			Canada (PDF)

35316

			1.97 ct Anatase
			Brazil (PDF)

33918

			10.62 ct Andalusite
			Brazil (PDF)

33922

			13.22 ct Andalusite
			Brazil (PDF)

33924

			14.41 ct Andalusite
			Brazil (PDF)

33917

			16.13 ct Andalusite
			Brazil (PDF)

34263

			16.71 ct Andalusite
			Brazil (PDF)

34773

			2.25 ct Andalusite
			Sri Lanka (PDF)

33919

			9.04 ct Andalusite
			Sri Lanka (PDF)

35307

40.83 ct Anglesite
			Morocco (PDF)

34682

			13.47 ct Anglesite
			Locality not stated (PDF)

34684

			16.10 ct Anglesite
			Locality not stated (PDF)

35306

			17.54 ct Anglesite
			Locality not stated (PDF)

34967

			9.55 ct Anhydrite
			Locality not stated (PDF)

35327

			2.35 ct Apatite
			Brazil (PDF)

34265

			4.94 ct Apatite
			Brazil (PDF)

34266

			7.10 ct Apatite
			Brazil (PDF)

35323

			2.23 ct Apatite
			Madagascar (PDF)

33785

			3.60 ct Apatite
			Madagascar (PDF)

35325

			5.12 ct Apatite
			Madagascar (PDF)

34401

			9.10 ct Apatite
			Madagascar (PDF)

33765

			16.69 ct Apatite
			Mexico (PDF)

34447

			22.42 ct Apatite
			Mexico (PDF)

33783

			3.03 ct Apatite
			Myanmar (PDF)

34648

			4.80 ct Apatite
			Myanmar (PDF)

34546

			6.50 ct Apatite
			Myanmar (PDF)

34548

			11.29 ct Apatite
			Myanmar (PDF)

34760

			17.09 ct Apatite
			Sri Lanka (PDF)

34999

			3.10 ct Apatite
			Tanzania (PDF)

33779

			1.60 ct Apatite
			The United States (PDF)

35160

			2.64 ct Apatite
			The United States (PDF)

35161

			6.33 ct Apatite
			The United States (PDF)

35267

			15.54 ct Apatite
			Zimbabwe (PDF)

35251

			25.27 ct Apatite
			Zimbabwe (PDF)

35331

			7.48 ct Apophyllite
			India (PDF)

35333

			8.07 ct Aragonite
			Czech Republic (PDF)

35334

			2.83 ct Augelite
			The United States (PDF)

33911

			4.29 ct Axinite
			Mexico (PDF)

33910

			8.71 ct Axinite
			Mexico (PDF)

34448

			9.10 ct Axinite
			Mexico (PDF)

34780

			8.30 ct Axinite
			Sri Lanka (PDF) @chapter:14 @chapter:0 @chapter:14


# Publication Year: 2018
# Title: Separating Glass-Filled Rubies Using the DiamondView
# Abstract: Figure 1. A pair of rubies that were determined to be glass filled, partly with the assistance of DiamondView imaging. Photo by Lai Tai-An Gem Lab.

The treatment of gemstones using various filler materials is not new. In the case of corundum, silica glass was often observed filling rubies from approximately 1980 to the early 2000s, when it was largely replaced by high-lead-content glass in early 2004 (S.F. McClure et al., “Identification and durability of lead glass–filled rubies,” Spring 2006 G&G, pp. 22–34) which has since become the mainstream artificial filler in corundum. The Lai Tai-An Gem Lab in Taipei recently examined a pair of rubies (figure 1) that were quickly determined to be glass filled with the assistance of DiamondView imaging. In our experience, the DiamondView detects the presence of glass, although it does not distinguish between different types of glasses. This note shows how the DiamondView can be used to observe the presence and, perhaps more importantly, the degree of filling in rubies.
The two heart-shaped cabochons weighed 6.81 and 6.89 ct and measured approximately 10.78 × 13.55 × 5.39 mm and 11.36 × 13.10 × 5.47 mm, respectively. Each semitransparent stone exhibited a purplish red color and fluoresced a strong red to long-wave ultraviolet radiation while exhibiting a weak red reaction to short-wave ultraviolet irradiation. Standard gemological testing showed spot refractive indices of 1.76, and specific gravities of 3.94 and 3.93, respectively, which were lower than regular values and raised suspicion that the stones were filled, while advanced analysis by energy-dispersive X-ray fluorescence (EDXRF) and Fourier-transform infrared (FTIR) spectroscopy and Raman microscopy revealed data consistent with ruby. Magnification with a gemological microscope revealed natural fluid and fingerprint inclusions, but some evidence of a filler was also observed in the fractures.

Figure 2. Notable differences in the reflectance of the glass filling and corundum host were seen in the DiamondView’s visible light mode.

Figure 3. In contrast to figure 3, the DiamondView’s operational mode clearly revealed the glass-filled cavities as well as the extent of the glass (shown in blue) running throughout the rubies.
Under the DiamondView’s visible light settings, some surface-reaching filler features and filled “cavities” were also revealed. Notable differences in the surface reflectance between the filling material and surrounding corundum (figure 2) were clearly evident. After exposure to the DiamondView’s short-wave UV radiation, the treated nature of both rubies was even more apparent as the reaction not only showed the obvious cavities but the extent of the filler (in blue) running throughout the stones (figure 3). The 6.81 ct ruby revealed an even greater degree of filling than its twin, especially on the base where a greater concentration of filling material was noted.
As the DiamondView results prove, filler materials penetrate or remain on the fractures of the treated material (ruby in this case) under certain treatment conditions. Hence, some filling treatments may be revealed more clearly when exposed to the ultra-short-wave energy of the DiamondView. Chemical analysis of a filled area using EDXRF detected Si and Ba as the major elements. Minute levels of Pb were also obtained. The results proved the filler was a glass composed of these elements, which were not detected when other filler-free areas were analyzed.
Artificial glass is frequently used as a filling material in gemstones. The variable chemical compositions of these different glasses help improve the appearance (lower visibility of fractures) of the host after treatment. While the vast majority of glasses and other fillers, both organic and inorganic, can be detected with a loupe or microscope, the DiamondView is a useful identification aid should the need arise. @chapter:19 @chapter:0 @chapter:19


# Publication Year: -
# Title: GIA Field Gemologists Visit Chimwadzulu Ruby Mine, Malawi
# Abstract: Seeking Ruby and Sapphire in Malawi

	Visit Malawi’s Chimwadzulu ruby mine with GIA field gemologists.

	In this video, you will experience the “warm heart of Africa,” as GIA field gemologists visit Malawi’s Chimwadzulu ruby mine for the very first time. Although this is one of the continent’s oldest-known ruby and sapphire deposits—discovered in 1958—it’s largely unknown to the gem trade or public at large.

	Malawi is one of the smallest African nations, bounded by Zambia to the northwest, Tanzania to the northeast, and Mozambique to the east, south, and west. The country is separated from Tanzania and Mozambique by the waters of Lake Malawi.

	“I read about Chimwadzulu a very long time ago…and this is a place I’ve wanted to come to for a very long time,” says GIA Field Gemologist Vincent Pardieu. The deposit’s geology is very complex, he explains, and the mine’s sapphires provide a key to understanding it. Although the Chimwadzulu deposit is known for ruby and orange sapphire, it produces mainly pale green, blue, and yellow sapphire.

	As always, a core goal of the expedition is to procure samples for GIA’s research programs, but understanding the gems as part of the geology and the mining operation—along with the people who labor to produce it—is also tremendously important. “When you look at the stone, you don’t view it the same way when you have the story of the stone, too,” explains Pardieu.

	The country is struggling to develop, and ethical stewardship of its gem resources is a part of the solution. Some of the possible benefits to local communities are a hospital and a school funded by the Chimwadzulu mining operation—a consortium between Nyala Mines Ltd. and Columbia Gem House, Inc.

	Pardieu and his team were able to visit the facility and observe the difference it makes. “In many African countries, the right access to education and health is really a luxury,” remarks Pardieu. “…you’re bringing to these people what is normal for us, but a luxury for them.” They also visited the elementary school, gaining a snapshot of the country’s youth and their boundless potential if Malawi’s resources can be harnessed for the good of all its citizens.

	This GIA Field Expedition (FE56) took place in September 2014. Besides Pardieu, the participants were cameraman Didier Gruel and field gemologist trainee Stanislas Detroyat. @chapter:40 @chapter:0 @chapter:40


# Publication Year: 2007
# Title: A Study of Nail-head Spicule Inclusions in Natural Gemstones
# Abstract: Nail-head spicules are inclusions that have traditionally been associated with hydrothermal synthetic quartz and emerald. They are caused primarily by rapid growth conditions and disturbances during crystallization of their host. However, these or similar-looking inclusions have also been found in natural gems. The authors examined a natural emerald and blue sapphire showing true nail-head spicules, and a yellow sapphire, spinel, diamond, and rock crystal quartz with inclusions that strongly resembled them. Nail-head spicules remain a notable feature of rapid and disturbed growth, but they do not confirm a stone’s natural or synthetic origin without further examination. @chapter:10 @chapter:0 @chapter:10


# Publication Year: 1991
# Title: Spring 1991 G&G Lab Notes
# Abstract: Inscribed Alexandrite
Chalcedony "Turquoise" Color
Highly Conductive Blue Diamond
"Emerald" with Unusual Color Zoning
More Banded Lapis Lazuli
Moonstone and Iolite Beads
Pearls from Baja California
Uncommon Cultured Pearls
Period Jewelry
Synthetic Ruby "Manufactured" Mineral Specimen
Flux Grown Ruby
Diffused Star Sapphire Update
Synthetic Sapphire with Triangular Inclusions

To view the full section, download the PDF above. @chapter:16 @chapter:0 @chapter:16


# Publication Year: 1957
# Title: New or Unusual Gem Materials Encountered in the Institute’s Gem Trade Laboratories
# Abstract: One of the favorites for Gems & Gemology readers is the Lab Notes column, the brief reports in each issue describing notable or unusual gem materials that have made their way to GIA’s laboratory. In this inaugural column from Summer 1957, Robert Crowningshield launches an enduring tradition, sharing discoveries about materials as diverse as rocks masquerading as minerals, a so-called television stone, an imitation moonstone, and dyed green jadeite. @chapter:21 @chapter:0 @chapter:21


# Publication Year: -
# Title: Bench Tip #6: Use a Split Mandrel for Finishing Round Bezels
# Abstract: Finishing round bezels

A bench jeweler typically uses a split mandrel to sand and finish the inside of a ring. Various grits of abrasive papers can be cut to size and inserted into the slit of the mandrel, where they are held by friction during the rotary filing process. With minor modification, you can use the split mandrel as a holding device to finish round bezels and other small jewelry components quickly and consistently.

	You can modify a standard split mandrel so it will hold small jewelry components for finishing.
To illustrate this, we will make a bezel for a gemstone measuring 4.5 millimeters round. The bezel will be hand-fabricated from 4 x 1 mm sterling silver flat wire. To determine the length of flat wire required to fabricate the bezel, multiply the gem’s diameter (4.5 mm) by pi (3.14) to find its circumference, which equals 14.13 mm. The bezel is cut from the flat wire, formed, soldered, then rounded and trued. The truing step, typically accomplished with a ball- or setting-style bur, is critical to rounding the inside of the bezel.

You will need to make a minor modification to the split mandrel to fit and hold the bezel for this use. Calipers, dividers and an equaling file will be required. The outside diameter of the split mandrel measures 5.5 mm and the inside diameter of the hand-fabricated bezel measures 3.5 mm, so the split mandrel must be filed down.

With the mandrel secured in the hand piece, brace it and start spinning the flexible shaft at a moderate speed. Place the equaling file flat against the mandrel shaft about 3.0 mm from the top of the tool and apply adequate pressure to begin filing down the mandrel shaft. Continue filing until the shaft diameter is reduced to 3.8 mm.

Next, squeeze the upper shaft of the split mandrel and place the bezel on it so it extends about 0.5 to 1.0 mm above the top of the tool. This makes it possible to sand the top of the bezel, too. The bezel will be held firmly in place by the tension of the split mandrel throughout the remaining steps in the finishing process.

	This split mandrel has been modified by filing down the end of the shaft.
The flexible shaft can be spun at moderate speed, and a variety of abrasives can be placed against it to smooth and polish. This technique also gives you greater hand-eye control to apply the surface finish on small areas.

	Place the bezel on the mandrel for finishing.
A modified mandrel gives you a dual-purpose tool for sanding or cleaning up bezels and other small parts. The next installment of the GIA Insider will present a stone-setting application using a different modification of the split mandrel. @chapter:38 @chapter:2 @chapter:38


# Publication Year: 2005
# Title: A Gemological Study of a Collection of Chameleon Diamonds
# Abstract: Chameleon diamonds are among the rarest of gem diamonds. This article reports on a unique collection of 39 chameleon diamonds ranging from 0.29 to 1.93 ct, which exhibited temporary changes in color when heated to approximately 150°C and, for some, after prolonged storage in the dark (i.e., thermochromic and photochromic color changes, respectively). Most changed from “olive” green to brownish yellow or yellow, although some changed from light yellow to a more intense greenish yellow. The thermochromic and photochromic color change observed in the “olive” green chameleon diamonds is typical of “Classic” chameleons, whereas the solely thermochromic change shown by the light yellow group was the “Reverse” of that seen in Classic chameleon diamonds. The Classic and Reverse groups showed different spectroscopic and UV fluorescence characteristics, but all stones exhibited strong long-lasting phosphorescence after shortwave UV excitation. Hydrogen was identified in all samples by FTIR spectroscopy, and minor Ni-related emissions were detected by photoluminescence spectroscopy in most. Using this combination of reaction to UV radiation and spectroscopic properties, a gemologist can separate chameleon from other green diamonds without unnecessary exposure to heat. @chapter:29 @chapter:1 @chapter:29


# Publication Year: 2023
# Title: In-depth Market Report on the Jewelry and Gemstone Market in the United Kingdom.
# Abstract: The situation of import and export of jewelry and ornaments in the responsible market is as follows:

Import
In 2021, the United Kingdom imported jewelry (HS code 71) worth 82,648 million US dollars, a decrease of 22.95% from 2020. The top 5 import markets were Russia (21.10%), the United States (15.04%), Canada (11.82%), South Africa (9.12%), and Switzerland (6.36%). Thailand ranked 27th with a market share of 0.37%. The main imported products were gold (53,897 million USD), platinum (11,884 million USD), and silver (6,199 million USD).

Export
In 2021, the United Kingdom exported jewelry (HS code 71) worth 65,814.79 million US dollars, an increase of 56.41% from 2020. The top 5 export markets were Switzerland (34,357 million USD), Germany (5,186 million USD), Hong Kong (3,415 million USD), the United States (3,305 million USD), and the UAE (2,790 million USD). Thailand ranked 39th with a value of 1,789 million USD. The main exported products were gold (41,396 million USD), platinum (13,637 million USD), and silver (3,636 million USD).
The trends in the jewelry and ornaments industry in 2023 in the responsible market:

After the COVID-19 pandemic, the jewelry and watch markets have rebounded, especially the bridal jewelry market and the return of international tourism, which has positively impacted the jewelry and watch market.

According to a study by Mintel, while consumers in the UK are currently facing a cost of living crisis, they are trying to reduce expenses by cutting down on non-essential purchases, especially in fashion items, impacting the mid-market and independent brands. Therefore, retail traders must have strong online sales channels and offer in-store shopping experiences to attract consumers to spend. However, in the high-end jewelry and watch market in the UK, it has not been significantly affected by the economic downturn because affluent consumers continue to purchase luxury jewelry and watches, considering high-end products as valuable assets. Additionally, Mintel found that consumers are placing increasing importance on sustainability and transparency in the origin of diamonds and jewelry.

Opportunities for Thai jewelry and ornaments in the responsible market:

Thai jewelry and ornaments still have potential in the UK market due to their quality and beautiful designs. However, due to the economic crisis in the UK, consumers are reducing spending, impacting the mid-market and independent brands more than high-end products
Therefore, entrepreneurs should continuously develop designs and maintain product quality to increase competitiveness in this market, especially in the high-end jewelry market.

Past achievements in driving the Thai jewelry and ornaments industry:

Participation in the Bangkok Gems & Jewellery Fair 2022 and collaboration with Jewellery Outlook magazine. Also, inviting representatives from the department to participate in a forum with Jewellery Outlook media through Insta live to invite UK visitors to the Bangkok Gems & Jewellery Fair 2022. @chapter:32 @chapter:3 @chapter:32


# Publication Year: -
# Title: Tanzanite Journey
# Abstract: Few people outside the gem industry realize the true nature of a gemstone’s journey from the mine to the counter of a store. Whether the gem is being offered to consumer’s at a traditional jewelry store’s counter, an internet shopping site, or a television broadcast the journey always involves a great deal of effort.  Tons of earth and countless hours of labor are needed to being a gem from mine to
market. @chapter:33 @chapter:2 @chapter:33


# Publication Year: -
# Title: U.S. Seasonal Shopping Diversifies Away from “Black Friday”
# Abstract: This necklace and ring, which consists of 11 translucent green jadeite cabochons, sold for a record $11.8 million at Tiancheng, a Hong Kong auction house, on Dec. 7. Photo courtesy Tiancheng

                      While retail analysts puzzle over the reported steep drop in post-Thanksgiving shopping numbers, online sales have risen strongly and there is growing evidence that seasonal buying may be becoming more diffused over a variety of retail channels. Indeed, indications point to a good season for U.S. jewelers, which account for 38% to 40% of world sales.

The National Retail Federation (NRF) reported that Black Friday – the day that typically opens the holiday shopping season – saw a 5.2% drop in traffic from 2013, with consumers planning to spend an average of 6.4% less. The NRF notes, however, that shopping is a 24/7 deal and more and more consumers have taken to smartphones, tablets and online services to make purchases.

Online purchases during Thanksgiving weekend and “Cyber Monday” rose 17% from 2013, according to comScore, the ecommerce research organization. Other reports noted that the growth in online sales came mainly from traditional retailers who have improved their online selection and buying experience.

Additionally, the movement to buy from local merchants appeared to gain strength this season, which could be one reason for the positive numbers reported by Centurion Luxury Jewelry Index. Centurion noted that more than 43% of luxury jewelers surveyed reported sales increases greater than 10% while another 23.5% logged sales increases between 1% and 10%. Some 13% said sales ran even with last year and 10% reported slight declines.

The survey also found that many shoppers, who traditionally waited until the final week before Christmas to buy, were making their purchases earlier.

A study by the U.S. Bureau of Labor Statistics, reported by Idex, on who buys jewelry indicated one obvious fact: The wealthiest buy the most. Those earning $150,000 or more a year bought 23% of the jewelry sold in the U.S. The study also reported, however, that those households earning between $40,000 and $90,000 yearly bought 42% of jewelry sold in the country.

Publicly traded retail jewelers reported mixed results for the third quarter of the calendar year, which ended Nov. 1.

Signet Jewelers, which operates Kay Jewelers, Jared Galleria and the recently acquired Zale Corp. in the U.S., reported overall same store sales growth of 4.2% and a 96% jump in online revenues against the same quarter of 2013. Online sales, however, remained a small part of Signet’s operation, accounting for sales of $44.8 million against total revenues of $1.18 billion. The Sterling brands saw a 6.8% sales increase, while Zales’ logged a decrease of 0.9%. Signet, which operates a diamond manufacturing plant in Botswana, also announced it has been named a De Beers’ sightholder, a move “that will advance its diamond sourcing efforts.”

Tiffany & Co. reported that its third quarter same-store sales rose 4% for the quarter.

By market: North American sales were up 11%; down 3% in the Asia-Pacific region (excluding Japan); down 6% in Japan; and up 2% in Europe.

In China, Chow Tai Fook, the region’s largest retailer, reported that revenues fell 22% for the quarter that ended Sept. 30. The steep decline, however, was measured again the 2013 “gold rush” that followed an abrupt decline in the price of gold. By contrast, demand for gem-set jewelry increased 25%.

AUCTIONS: The auctions have continued their record-breaking sales this fall.

Sotheby’s was expecting $15 million for a GIA-graded 9.75 carat (ct.) Fancy Vivid blue diamond from the estate of Mrs. Paul Mellon that went up for auction Nov. 21 in New York. It wound up getting more than twice that amount from a Hong Kong buyer: $32.6 million.

At $3.38 million per carat, it is far and away the highest per-carat price ever paid for any gemstone (the previous record was $2.3 million for a vivid pink diamond). It is also the highest price ever achieved by a blue diamond and the second highest price ever paid for any gem.

The buyer, not named by Sotheby’s, issued a statement that it would be named the Zoe Diamond.

Four days later in Hong Kong, Christie’s sold a 2.09 ct. Fancy red heart shape diamond, graded by GIA, for $5.09 million or $2.44 million per carat. It was the highest price ever paid for a red diamond at auction.

On Dec. 7, Tiancheng, the Hong Kong auction house, sold a cabochon jadeite necklace and ring for a record $11.8 million. The suite contained 11 translucent green jadeite cabochons, the largest a pendent measuring 25.10 x 20.39 x 8.55mm.

Gemfields’ second auction of rubies from its Montepuez mine in Mozambique achieved a record $698 per carat and saw its largest find to date, a 40.28 ct high quality ruby, go to a New York gem dealer.

The company sold more than 63,000 carats of high quality material for $43 million at its Dec. 8 Singapore auction. Fifty dealers from around the world bid on the rubies that were divided into 41 lots. When the bids were tallied, 35 of the lots met their reserve price and were sold to the high bidders.

The large ruby went for an undisclosed price to a dealer from New York, said Vincent Pardieu, GIA senior manager of field gemology, who noted that the company had named it the “Rhino Ruby” to raise the awareness about conservation issues in Africa.

After the sale, Gemfields announced that a portion of the proceeds from the sale of this gem will go toward efforts to halt poaching of rhinoceros in game preserves along the country’s long border with South Africa.

Gemfields began operating the Montepuez concession in 2012. It conducted its first auction in June 2014 with sales totaling $33.5 million.

	Buyers from KV Gems of Thailand study a ruby parcel at the Gemfields auction in Singapore. Photo by Vincent Pardieu/GIA @chapter:32 @chapter:3 @chapter:32


# Publication Year: 2023
# Title: GIA Museum’s “Paint the Town Ruby Red” Exhibit at TGMS
# Abstract: The GIA Museum’s “Paint the Town Ruby Red” exhibit at TGMS featured a Burmese ruby and diamond necklace and earrings, courtesy of Mona Lee Nesseth (Custom Estate Jewels) and a private collector. Photo by Terri Ottaway.
At the Tucson Gem and Mineral Show, the GIA Museum exhibited a Burmese ruby and diamond necklace and earrings against a backdrop of the necklace fluorescing in ultraviolet light (see above). The necklace contains 39 untreated rubies from Mogok totaling 83.73 carats and 302 diamonds totaling 42.62 carats. The largest ruby is 5.00 ct.
The exhibit highlighted the “magic ingredient”—chromium—that gives ruby not only its color but also its fluorescence. Mogok rubies are renowned for their high concentration of chromium and low concentration of iron. The latter element, if present in a high enough concentration, quenches all or part of the red fluorescence produced by the chromium. This fluorescence is an important factor in the high value of Mogok rubies.
TGMS began in 1955 and is one of the longest-running gem and mineral shows in the world. GIA Museum curator Terri Ottaway said she was thrilled at the opportunity to showcase such a gorgeous necklace and include a bit of chemistry and geology for the gem and mineral enthusiasts. @chapter:40 @chapter:0 @chapter:40


# Publication Year: 2014
# Title: Books: Unique by Design: Contemporary Jewelry in the Donna Schneier Collection
# Abstract: By Suzanne Ramljak, 136 pp., illus., publ. by the Metropolitan Museum of Art, New York, 2014, $25.00.

              This book documents the eponymous 2014 exhibition organized by New York’s Metropolitan Museum of Art. As the museum does not provide an exhibit booklet, this is the only available guide to the collection of art and jewelry dealer Donna Schneier. Now retired, Schneier donated her collection of significant studio jewelry pieces to the Met in 2007.

The core of this volume is a chapter titled “Seductive Tactics.” Rather than a systematically documented catalog, this chapter is actually a general essay on contemporary jewelry. Most of the examples and illustrations in the book are pieces from the collection. Maisie Broadhead’s three conceptual pieces, collectively titled “Which Weigh to Go,” are a notable exception. The first of the three pieces is a photo showing a pastiche of a Vermeer painting, depicting a young woman weighing a pearl.  The two other photos are the necklaces in the background of the previous, a gold link chain titled “Big Fake Little Real Chain” and a freshwater pearl necklace named “Big Fake Little Real Pearl.” The “Plates” chapter features more photos that highlight of the collection, such as “Brass Knuckles, a four-finger ring by Myra Mimiltsch-Gray. No explanation is provided as to the motive for this photo selection. The last chapter of the book is a very succinct bibliography on contemporary jewelry.

One strong point is the book’s use of clinically precise color photos, some showing appreciable texture and surface details. The rendering of those photos is uniform throughout the book, which is rare. The use of those pictures is partially illustrative, as this book is more art essay than a catalog. As is usual in this type of book, jewelry measurements and carat weight are not noted, and magnification is not mentioned. To properly catalog the exhibition, the book should have contained a section presenting the 132 displayed pieces, with thumbnail pictures, detailed descriptions, measurements, artist biographies, and details on how the pieces were acquired. The book gives very little insight on the collection itself and does not answer one legitimate question: If the collection was donated in 2007, why show it now?

Overall, Unique By Design reads like a general introductory art essay to studio jewelry rather than a guide to a specific exhibition. Therefore, it is more suited to jewelry students and art collectors with an interest in studio jewelry. @chapter:20 @chapter:2 @chapter:20


# Publication Year: 2016
# Title: Paula Crevoshay’s American Collection, Plus Jewelry with Nontraditional Gemstones
# Abstract: Figure 1. The “Rainbow Over Montana” bracelet contains 76.83 carats of Montana sapphire (71.42 carats rough and 5.41 carats faceted). The ring from the same collection contains 11.57 carats of rough and 1.12 carats of faceted Montana sapphires. Photo by Robert Weldon/GIA; courtesy of Paula Crevoshay.

Paula Crevoshay’s American Collection, created as a cultural and artistic inheritance for future generations, featured gemstones from the United States. The first pieces we saw were from her “Rainbow Over Montana” collection of rough and faceted Montana sapphires (figure 1). She used the faceted sapphires to show “the story of light” told by the gemstone after the human contribution of cutting, while the crystal slices display the natural hexagonal shape and luster of the flat crystal faces. The blue faceted stones represent the “Big Sky Country” of Montana, and the crystals demonstrate the range of rainbow colors in Montana sapphire.

The next piece was a pin featuring a 31.34 ct bicolor pink and green tourmaline (figure 2) from the Stewart Lithia mine in San Diego County, California. The stone was purchased back from a customer who had bought it from Paula’s late husband, George Edward Crevoshay, who first cut the stone more than 30 years ago. The pink and green tourmaline melee in the piece was also cut by Mr. Crevoshay and came from the Stewart Lithia mine. Besides featuring gemstones from a famous U.S. mine, this piece carries the sentiment of a great love that inspired Paula Crevoshay to move from painting and sculpture into the world of gemstones and creating jewelry.

Figure 2. This 31.34 ct bicolor tourmaline pin, which contains gemstones exclusively from the Stewart Lithia mine in San Diego County, has an emotional connection for the artist. Photo by Robert Weldon/ GIA; courtesy of Paula Crevoshay.
The third piece (figure 3) was a ring that contained one of the most intense red Oregon sunstones the authors had ever seen. The stone features the trademarked “Medicine Wheel” cut by award-winning lapidary Larry Woods. The ring also contains red spinels and diamonds.

Figure 3. While not as large as some of the other colored stones used by Paula Crevoshay,
the intense color and unique cut of the 2.77 ct Oregon sunstone makes this ring one of her
favorite pieces. The center stone’s color is complemented by 3.24 carats of red spinel.
Photo by Robert Weldon/GIA; courtesy of Paula Crevoshay.
While visiting her booth at the AGTA show, the authors also noticed some nontraditional stones ingeniously incorporated into jewelry. The first two pieces we viewed contained center stones of sphalerite (figure 4, left) and sphene (figure 4, center), both in pendants. For Ms. Crevoshay, creating jewelry is all about working with light. How she selects and combines gems depends on properties such as refractive index, bodycolor, luster, and phenomenal optical effects.

Figure 4. These Paula Crevoshay jewels include gems not typically used in jewelry. Left: The 8.25 sphalerite pendant creates an eye-catching fire, complemented by the play-of-color of the opal and the colorful sparkle of the diamond melee. Center: The green color of the 11.78 ct sphene pendant is accentuated by tsavorite melee, with the orange fire opals offering a striking contrast. Right: This dragonfly pin features a 38.24 ct hematite drusy as the insect’s body. The drusy’s iridescence and sparkle creates a shimmering effect that is intensified by the orient of the Tahitian cultured pearl used for the head. Photos by Robert Weldon/GIA; courtesy of Paula Crevoshay.
Both sphalerite and sphene are highly dispersive, and the flashes of rainbow color created by the dispersion excite the eye. For the sphalerite piece, she added Mexican opals showing a rainbow of colors, combining a highly dispersive gem with phenomenal accent stones to create a dance of colors across the pendant. The pendant also contains cognac and colorless diamonds to create even more of a symphony of colors. Ms. Crevoshay chose the sphene for its high dispersion and her attraction to the green bodycolor. As with the sphalerite pendant, she added Mexican opals showing a subtle rainbow of phenomenal colors. With both pieces, she combines gemological knowledge with art to create jewelry that paints with the surrounding light.

Another piece that caught our attention was a dragonfly containing rainbow hematite drusy as the insect’s body (figure 4, right). With the hematite, Ms. Crevoshay was able to highlight the iridescent colors and sparkle of the drusy. She finds that the rainbow colors of the hematite are not as bold as those caused by dispersion from the sphene and sphalerite but still have a seductive effect.

Public awareness of gemstones such as sphene and sphalerite has been growing thanks to high-end designers such as Paula Crevoshay and through mass marketing of commercial jewelry on television. Ms. Crevoshay told us she often piques customers’ interest by informing them about some of these lesser-known gem materials and how light interacts with them. The authors found this to be a fascinating look at how stones that were once a gemological novelty are becoming more widely known. @chapter:33 @chapter:2 @chapter:33


# Publication Year: -
# Title: Sapphire Description
# Abstract: Sapphire comes in a variety of colors. This rare 1,126.00-ct. corundum crystal’s pinkish orange color is called padparadscha, named after the lotus flower. - © GIA & Tino Hammid

                      Blue sapphire belongs to the mineral species corundum. It can be a pure blue but ranges from greenish blue to violetish blue. The name “sapphire” can also apply to any corundum that’s not red and doesn’t qualify as ruby, another corundum variety.

	Deep, intense, velvety blue is the best way to describe the color of this sapphire from the Kashmir region on the India/Pakistan border. - Courtesy Edward Boehm, JOEB Enterprises, Chattanooga, Tennessee

	Most people who think of sapphire picture the color blue. - Courtesy Bulgari
Besides blue sapphire and ruby, the corundum family also includes so-called “fancy sapphires.” They come in violet, green, yellow, orange, pink, purple, and intermediate hues. There are also “parti-colored” sapphires that show combinations of different colors. Some stones exhibit the phenomenon known as color change, most often going from blue in daylight or fluorescent lighting to purple under incandescent light. Sapphires can even be gray, black, or brown.

	Stunning jewelry designs can be created by combining different sapphire colors.
	- Jeff Scovil
Fancy sapphires are generally less available than blue ones, and some colors are scarce, especially in very small or very large sizes. Still, fancy sapphires create a rainbow of options for people who like the romance associated with this gem, but who also want something out of the ordinary.

	Sapphires come in every color except red. Red corundum earns the name “ruby.” - Courtesy Omi Gems, Inc. Los Angeles, CA, USA
The mineral corundum is composed only of aluminum and oxygen, and it requires a growth environment that’s free of silicon. However, silicon is a very common element, making natural corundum relatively uncommon. In its purest state, corundum is actually colorless. Colorless sapphires were once popular diamond imitations, and they’ve staged a comeback as accent stones in recent years.

But colorless corundum is rare. Most corundum contains color-causing trace elements. When the trace elements are iron and titanium, the corundum is blue sapphire. Only a few hundredths of a percent of iron and titanium can cause the color, and the more iron the corundum contains, the darker the blue. Chromium can cause the red color of ruby or the pink of pink sapphire.

In the 1990s, discoveries in East Africa and Madagascar brought fancy sapphires widespread recognition. The new sources supplemented production from traditional ones like Sri Lanka and Madagascar and increased the availability of yellows, oranges, pinks, and purples.

The colors attracted jewelry designers who wanted to move away from traditional hues of red, blue, and green. Now, contemporary designers arrange fancy sapphires in stunning rainbow suites.

Corundum can show a phenomenon called asterism, or the star effect. This phenomenon usually appears as a six-ray star pattern across a cabochon-cut stone’s curved surface. The star effect can be seen in ruby or any color of sapphire, and it arises from white light reflecting from numerous tiny, oriented needle-like inclusions.

Besides fancy sapphire and star corundum, there’s another interesting variety: color-change sapphire. These fascinating stones change color under different lighting. Their presence adds a special dimension to the already amazing corundum family of gems.

Both blue and fancy sapphires come from a variety of exotic sources including Madagascar, Tanzania, Sri Lanka, Myanmar, and Australia. @chapter:30 @chapter:0 @chapter:30