Publication Year: 2016 Title: Purple Pyrope-Almandine Garnet From Mozambique Abstract: Figure 1. These purple pyrope-almandine garnets are from Manica Province of Mozambique. The rough specimens weigh (clockwise from left) 1.49, 1.14, 1.11, and 1.77 ct, while the faceted stone in the center weighs 2.34 ct. Photo by Lhapsin Nillapat.

	In early 2016, attractive purple garnets from East Africa started to appear in the Bangkok market (T. Sripoonjan and T. Leelawatanasuk, “Preliminary investigation of purple garnet from a new deposit in Mozambique,” GIT Gemstone Update, 2016, pp. 1−6). Author VP purchased 17 samples (figure 1) at the Bangkok Gem Fair and inquired about their origin. Mark Saul of Swala Gem Traders (Arusha, Tanzania) informed him that the source was a very unstable area of Manica Province in central Mozambique. Ameen Ikram, a gem merchant from Sri Lanka, confirmed this after managing to visit the mining site in June 2016. The deposit is located about 60 km northeast of Chimoio, near Gorongosa National Park. The area is under the control of the Mozambican National Resistance (RENAMO), an armed rebel group.

	The stones exhibited a vitreous luster. Standard gemological testing yielded an isotropic RI reading of 1.767 ± 0.003 and an SG value of 3.87 ± 0.02. An isotropic reaction with anomalous double refraction (ADR) was observed through the polariscope. The samples were inert when exposed to both long-wave and short-wave UV radiation. Examination with a gemological microscope revealed several internal features (figure 2), including individual and clustered zircon crystals, zircons with stress halos, black platelets of graphite, groups of colorless quartz crystals, thin films, needles, tubes, and iron stains in tubes. Raman spectroscopy was used to identify the mineral inclusions.

	Figure 2. Magnification of the pyrope-almandine garnets revealed several internal features: (A) zircon inclusions with stress halos and needles, field of view 1.4 mm; (B) thin films, field of view 3.5 mm; (C) groups of colorless quartz, field of view 1.8 mm; and (D) a platelet of black graphite, field of view 1.8 mm. Photomicrographs by Victoria Raynaud.

	Advanced analytical techniques, including UV-Vis-NIR and Fourier-transform infrared (FTIR) spectroscopy and laser ablation−inductively coupled plasma−mass spectrometry (LA-ICP-MS), were used to collect additional information. The UV-Vis-NIR spectrum (figure 3, left) indicated electronic transitions of specific Fe and very weak Mn transition metal ions, as described in the literature (K. Krambrock et al., “Purplish-red almandine garnets with alexandrite-like effect: Causes of colors and color-enhancing treatments,” Physics and Chemistry of Minerals, Vol. 40, No. 7, 2013, pp. 555−562). All of the samples showed an iron spectrum including Fe2+ and Fe3+, and a weak absorption peak at 408 nm was assigned to Mn2+. The FTIR spectrum (figure 3, right) showed Fe2+ peaks at 4450 and 5820 cm−1 (R.G. Burns, Mineralogical Applications of Crystal Field Theory, Vol. 5, Cambridge University Press, Cambridge, UK, 1993, pp. 155−158), hydroxyl group features at around 3500−3600 cm−1 (G.R. Rossman et al., “Quantitative analysis of trace OH in garnet and pyroxenes,” American Mineralogist, Vol. 80, No. 5−6, 1995, pp. 465−474), and CO2 peaks at 2340−2360 cm−1. A minor FTIR peak at 2627 cm−1 might have resulted from the numerous inclusions in the samples. LA-ICP-MS analysis (table 1) revealed major amounts of Si, Al, Fe, and Mg, as well as minor amounts of Ca and Mn. Vanadium was also detected in very low concentrations, while titanium and chromium were below the detection limits. The LA-ICP-MS data confirmed the material’s identification as pyrope-almandine garnet with the following chemical components: 48.8−59.5% pyrope, 37.9−47.6% almandine, 2.0−3.5% grossular, and 0.5−0.6% spessartine.

TABLE 1. LA-ICP-MS analyses of pyrope-almandine garnets from Mozambique.

				Oxide

				Weight (%) ± SD (n = 5)

				SiO2

				42.34 ± 0.33

				Al2O3

				25.41 ± 0.22

				FeO

				17.93 ± 1.31

				MgO

				13.16 ± 1.19

				CaO

				0.94 ± 0.20

				MnO

				0.22 ± 0.02

				V2O3

				0.002 ± 0.001

				Cr2O3

				bdl

				TiO2

				bdl

					n: number of studied samples
					bdl: below detection limit
					SD: standard deviation

	Figure 3. Left: The purple garnet’s UV-Vis-NIR spectrum shows weak absorption bands attributed to Fe3+ (337, 367, and 424 nm) and Mn2+ (408 nm). The remaining peaks in the visible region (400, 461, 504, 523, 575, 619, and 698 nm) can be assigned to Fe2+. Right: The FTIR spectrum reveals Fe2+ bands at 5820 and 4450 cm–1, hydroxyl group features at 3552 and 3525 cm–1, and CO2 peaks at 2360 and 2341 cm–1. The very small peak at 2627 cm–1 may be caused by the samples’ numerous inclusions.

	The UV-Vis-NIR spectrum explains the purple color of the samples. Since the main absorption bands dominate the green-yellow regions of the visible spectrum, two strong blue and red transmission regions combine to produce an eye-visible purple color. These samples can be classified as pyrope-almandine garnet, commonly referred to as “rhodolite” garnet. @chapter:5


Publication Year: 2015 Title: Purple Scapolite Abstract: Figure 1. These two brownish purple specimens, a 1.58 ct oval and a 2.95 ct cushion, were identified through gemological testing as scapolite. Photo by Gagan Choudhary.

Two brownish purple faceted specimens (figure 1) were submitted for identification at the Gem Testing Laboratory, Jaipur, India. The 2.95 ct mixed cushion measured 9.95 × 8.05 × 5.88 mm, while the 1.58 ct mixed oval measured 9.07 × 7.08 × 4.46 mm. Both were relatively clean to the unaided eye. Based on their color, they were thought to be spinel, but testing soon proved otherwise. Testing yielded the following gemological properties: optic figure—uniaxial; RI—1.549–1.559; birefringence—0.010; and hydrostatic SG—2.63. The material fluoresced a weak orangy red under short-wave UV and was inert under long-wave UV. An absorption band was observed in the yellow-green region using a desk-model spectroscope. In addition, both samples displayed strong dichroism (figure 2) with deep saturated and pale purple colors along the “o” and “e” rays, respectively; this also influenced their face-up color. Under magnification, growth zones and two-directional cleavage planes intersecting at almost 90° were visible. The cleavage planes also contained some fine dendritic films; additionally, the oval specimen had an unidentified brown crystal.

Figure 2. The scapolite specimens displayed intense dichroism (shown here in the cushion), with a deep saturated purple along the o-ray (left) and pale purple along the e-ray (right). Photos by Gagan Choudhary.
These gemological properties were consistent with scapolite. Raman spectroscopy confirmed this, showing the characteristic peaks for scapolite at approximately 260, 296, 359, 418, 455, 534, 771, 993, and 1093 cm–1. The Raman spectra suggested the specimens belonged to the marialite end of the meionite-marialite solid solution series of the scapolite group (see rruff.info); this was supported by their RI and SG values (R. Webster, Gems: Their Sources, Descriptions and Identification, 5th ed., rev. by P.G. Read, Butterworth-Heinemann, Oxford, UK). Polarized absorption spectra (figure 3) revealed a broad absorption centered at approximately 550 nm in both specimens. The intensity of this absorption was stronger in the o-ray direction, while a weak hump at about 630 nm was also present in the e-ray direction. Such absorption bands, associated with Fe3+ ions and producing purple coloration, have been reported in sugilite (Spring 1995 GNI, pp. 66–67); however, additional Fe3+ features at approximately 350–365 and 410–420 nm were absent in both the “e” and “o” rays of those specimens. Qualitative EDXRF analysis revealed the presence of Al, Si, K, Ca, Fe, Br, and Sr. Mn is a common impurity resulting in purple coloration of stones such as kunzite or some sugilites, but it was not detected in these specimens. On the basis of absorption spectra and elemental analysis, the purple color of these scapolites appears to be caused exclusively by an Fe impurity.

Figure 3. Polarized UV-Vis spectra of the cushion-cut scapolite (shown here in the
cushion) displayed Fe-related absorption at approximately 550 nm, which is responsible
for the purple color of these specimens.
Purple scapolite is known from many localities such as Myanmar, Tanzania, and Tajikistan, but the client did not know the source of these stones. Although we have seen many purple to violet scapolites in the past, these specimens were different because of their brown color component, reminiscent of spinel. @chapter:13


Publication Year: 1989 Title: Contribution to the Identification of Treated Colored Diamonds: Diamonds with Peculiar Color-Zoned Pavilions Abstract: Some treated yellow and blue-to-green diamonds show a peculiar color zoning when viewed through the pavilion. The culet or keel-line area on such stones exhibits a bright yellow or blue color that contrasts with the otherwise lighter (and/or different) body color of the diamond (which does not show any other strong color zoning). Such peculiar color zoning near the culet or keel-line is a strong indication that the stone has been treated by electron irradiation. Although rare, this feature can be useful in identifying irradiated diamonds, especially some green diamonds, for which few criteria are available to separate natural-color from laboratory-treated stones. @chapter:31


Publication Year: 1997 Title: Summer 1997 Gem News International Abstract: Diamonds
            Conference on Diamond Technology
            A “Piggyback” Diamond Assemblage
            Synthetic Diamond Thin Film Jewelry
Colored Stones and Organic Material
            Color-Zoned Amethyst from Thunder Bay, Ontario, Canada
            Blue- and Multicolor-Sheen Moonstone Feldspar from India
            “Watermelon” Sunstone Feldspar Carving
            Musgravite: A Rarity among the Rare
            Faceted Cultured Pearls
            Inclusions in Quartz as Design Elements
Treatments
            A New Emerald Filler
Synthetics and Simulants
            Update on Vanadium-Bearing Synthetic Chrysoberyl
            “Cat’s-Eye” Synthetic Emerald
            Emerald Rough: Buyer Beware!
            An Especially Misleading Quench-Crackled Synthetic Ruby
            New Information on Flux-Grown Red Spinel from Russia

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


Publication Year: 2019 Title: Imitation Opal with Interesting Play-of-Color Pattern Abstract: Figure 1. This opal imitation shows a billowy play-of-color phenomenon. The largest block measures approximately 61.79 mm in length. Photo by Robison McMurtry and Diego Sanchez. Courtesy of Sanwa Pearl & Gems Ltd.

GIA’s Carlsbad laboratory recently examined samples of a relatively new manufactured gem material sometimes known as a “hybrid opal product” (figure 1) (see Spring 2018 Lab Notes, pp. 60–62). This material showed a refractive index of 1.498–1.500, and the specific gravity ranged from 1.33 to 1.35. Both of these properties fall far outside the range for natural opal, making identification very straightforward for the gemologist. These anomalous gemological properties also mean that this material is best described as an opal imitation and not a synthetic opal. This material is reportedly composed of about 20% silica and about 80% resin, which is consistent with the gemological properties measured.

Figure 2. The imitation opal showed broad swaths of the play-of-color phenomenon when examined with a microscope. Photomicrograph by Nathan Renfro; field of view 18.80 mm.
This new imitation opal showed a pronounced play-of-color phenomenon with a pattern unlike the kind one would expect to see in conventional synthetic opal. Instead of small cellular patches, it displayed broad swaths of ever changing play-of-color covering large areas of the surface (figure 2). The laboratory examined samples that showed either a black or white bodycolor and a variety of colors in the play-of-color areas. For those who love opal, this attractive material could offer a cost-effective alternative to natural material while retaining the allure of the play-of-color phenomenon. @chapter:39


Publication Year: 2016 Title: Iridescent Spondylus Pearl Abstract: Figure 1. This 6.97 ct bicolored white and pink Spondylus pearl shows prominent reflective blue coloration over the fine parallel flame structure when viewed in certain directions under a single white light source. Photo by Robert Weldon/GIA.

	The optical phenomenon of iridescence is frequently observed in gem materials, but it is uncommon to see iridescent colors in porcelaneous pearls. Such pearls are appreciated for their prominent eye-visible flame structures, such as those seen in some Queen conch and Melo pearls. Pearls from these gastropods, along with Spondylus species bivalves, are routinely submitted to GIA’s laboratory. A bluish reflective sheen is a common feature of the flames seen in Spondylus pearls (Fall 2014 Lab Notes, pp. 241–242; Winter 2015 Lab Notes, pp. 436–437).

	A 6.97 ct bicolored white and pink Spondylus pearl (figure 1) was recently examined at GIA’s Carlsbad laboratory. When a single white light was used to illuminate the pearl, a prominent reflective blue coloration over its fine parallel flame structure was visible on the white portions. This created a pseudochatoyant effect similar to other Spondylus pearls previously examined. What was particularly captivating about this pearl was that iridescent colors ranging from purplish to a dominant blue were seen on the fine, well-formed flame structure when a fiber-optic light was applied in certain directions (figure 2).

Figure 2. Under magnification and using fiber-optic illumination, iridescent colors ranging from purplish to dominant blue reflect from the fine, well-formed flame structure of this Spondylus pearl. Photomicrograph by Artitaya Homkrajae; field of view 2.34 mm.

	As with many gemstones and nacreous pearls, the spectral colors seen on the flame structure are the result of the interference effect of light reflecting off of structural features. In this case, the thickness of the aragonite lamellae permits white light to be diffracted into most of the visible light wavelengths, resulting in a colorful effect.

	The iridescence characteristics of this pearl have not been encountered to such a marked degree in any other porcelaneous pearl examined by GIA. @chapter:14


Publication Year: - Title: GemKids Introduces African Students to Natural Resources, Future Potential Abstract: Students at the Matshekge High School in Bobonong practice the MOHS Hardness Scale to test the hardness of minerals. Photo by GIA

	Thousands of African students are learning about the abundant natural resources found right in their own backyards through GIA’s GemKids program. The half-day workshops introduce the science of gemology with hands-on techniques that show the students why gemstones are a valuable resource.

	“The GemKids Program is a fun and fascinating introduction to gemology where students learn about gems from mine to market in an interactive environment,” said Elizabeth Bokaba, a GIA GemKids program instructor and coordinator. “Having taught several of these courses, it never ceases to amaze me how engaged the students are in this subject.”

	GIA’s GemKids Program was introduced in sub-Saharan Africa in 2012, and has taken place in Botswana, Cote d’Ivoire, Kenya, Namibia Tanzania and South Africa. Since March 2015, hundreds of students in rural Botswana, Namibia, South Africa and Tanzania have participated.

	“This program enables students to understand more about − and ultimately benefit from − their natural resources,” added Brad Brooks-Rubin, GIA’s director of global development and beneficiation.

Elizabeth Bokaba teaches a student how to use a Darkfield Loupe at the Matshekge High School in Bobonong, Botswana. Photo by GIA

Botswana

	Close to 100 students from in and around Bobonong, Botswana, participated in the GemKids program over the course of two days in May 2015.

	Although large-scale diamond production has dominated Botswana’s economy since the late 20th century and the country is the world’s largest producer of diamonds by value today, Bobonong, located in Botswana’s Central District, is a source of colored gemstones. These colored gems may provide future economic opportunities for the children who grow up there.

	Twenty students from each school – Matshekge Hill Senior Secondary School, Bobirwa Community Junior Secondary School, Bobonong Community Junior Secondary School, Molalatau Community Junior Secondary School in Molalatau and Mosethla Community Junior Secondary School in Gobojango – participated in the GemKids program, which was organized in conjunction with the Botswana Geological Survey.

Students from Enaboishv Secondary and Bishopdvrning school. Photo by GIA

Namibia

	Local students from Five Rand Primary School in Okahanadja, a small town in Namibia, participated in GIA’s GemKids program in March 2015 in association with local company NamGem. Okahanadja is a rich source of diamonds and gemstones; many of the students’ parents work in mining-related jobs.

	The students were able to learn about and identify stones they encounter on a daily basis, often at home.

	“I am very honored to be part of this event as we are investing in the youth, especially those who are from underprivileged backgrounds. This opens many doors and windows of opportunity for them,” said the mayor of Okahandja, Her Worship Valerie Aron.

	In late June/early July 2015, GIA representatives delivered the GemKids program to more than 200 students – from the Gamams, Academia, Eldorado, Namibia P.S., Sunshine School, M. Mclean and Van Ryn secondary schools – during the Namibia Science, Technology and Innovation Fair.

	The fair was organized by National Commission on Research, Science and Technology with direct support from the Namibian government. GemKids was offered twice per day during the fair, for a total of 10 sessions, to a large numbers of students.

GIA participated in the East London Career Fair, organized by local nongovernmental organization DSR Youth Empowerment, in King William’s Town, South Africa in early July 2015. Photo by GIA

South Africa

	GIA participated in the East London Career Fair, organized by local nongovernmental organization DSR Youth Empowerment, in King William’s Town, South Africa in early July 2015.

	During the event, the Institute hosted a booth and presented students from across the Eastern Cape with essential information about GIA’s education offerings and career opportunities in the gem and jewelry trade.

	GIA also offered its GemKids program to more than 40 students from schools across the province. This program built on GIA’s participation earlier in the year at Career Indaba in Johannesburg.

Students from Arusha Secondary School tour the Arusha Gem Fair 2015 after the GemKids program. Photo by GIA

Tanzania

	Secondary students got to experience a gem trade show when GIA offered its GemKids program for the first time at the Arusha Gem Fair in Tanazania in April 2015.

	Secondary students from four local schools had the opportunity to learn about the natural resources that are an integral part of their local economy and tour the Gem Fair’s trading booths.

	GIA coordinated this program with the Tanzania Gemmological Centre, also based in Arusha. @chapter:24


Publication Year: 2023 Title: Two Pearls of Indian Cultural Significance Abstract: Figure 1. The Lord Hanumana pearl (left, 33.70 × 32.98 × 24.64 mm) and the Lord Ganesha pearl (right, 10.59 × 10.21 × 9.18 mm). Photo by Gaurav Bera.
In India, pearls (also known as moti or mukta) and pearl-adorned jewelry have historically been coveted by the affluent and served as symbols of cultural importance for centuries. GIA’s Mumbai laboratory has tested various jewelry items set with pearls that were not only artistic in their design but also of great symbolic and religious significance. Two recent submissions consisted of pearls fashioned into the likenesses of Indian deities (figure 1). The first was skillfully crafted to resemble Lord Hanumana, an Indian deity from the epic Ramayana bearing the likeness of a vanara (an ancient race of forest-dwellers). The ornament had a total weight of 24.91 g, and its surface was partially drilled in several positions. Yellow metal fittings set with green, white, yellow, and black enamel formed the head, eyes, body, and striped tail. A translucent red stone set on the pearl formed the tongue of the deity (figure 2, left). This baroque pearl was white and light gray in color with orient and measured approximately 33.70 × 32.98 × 24.64 mm. When viewed under 40× magnification, its surface showed typical nacreous structure with overlapping aragonite platelets, and minor surface openings were present on some areas. Most of the surface had good nacre condition, but a few small areas of the nacre were damaged or worn, and remnants of an adhesive glue were visible around some of the decorative enamel inserts.

Figure 2. Left: External appearance of the Lord Hanumana pearl. Photo by Gaurav Bera. Right: RTX image showing the internal structure. Also indicated are the gemstone tongue, the eyes, the tail, the void, and the filling.
Energy-dispersive X-ray fluorescence (EDXRF) spectrometry analysis of the pearl showed manganese levels below the detection level of the instrument and a higher strontium content of 1188 ppm. In addition, an inert reaction to X-ray fluorescence (XRF) confirmed saltwater origin. A moderate greenish yellow reaction was observed under long-wave ultraviolet radiation, and a weaker reaction of a similar color was noted under short-wave UV radiation. Such fluorescence reactions in nacreous saltwater pearls are often associated with pearls from the Pinctada-species mollusk. Real-time microradiography (RTX) imaging revealed the presence of a very large void that appeared to have been partially filled with a foreign material (figure 2, right). The clearest evidence of the void was observed within the ornament’s head as a dark gray area beneath the nacre layer. The outline of this void was consistent with the external shape of the pearl, but the filling material partially masked the void in RTX and made it harder to see the complete structure clearly. (The radiopaque areas visible on the microradiographs represent the adornments decorating the pearl.) While large voids are more often associated with non-bead cultured pearls, the shape and form of this void resembled those associated with natural pearls. Hollow pearls are often filled (wholly or partially) with a variety of materials including wax, metal, resin, cement, and shell to increase the weight and inflate the perceived value (Winter 2022 Lab Notes, pp. 480–481). In the case of older pearls such as this one, filling can provide enough solid material within the pearl to support all the metal adornments, and it can also improve the durability of the item.

Figure 3. Front view of the Lord Ganesha pearl (left) with a line drawing of features (center) and back view (right). Photo by Gaurav Bera.

Figure 4. X-ray fluorescence reaction (left) and an RTX image showing the Lord Ganesha pearl’s internal structure (right). A small twisted void and discoid features can be seen in the center.
Also submitted was a pearl portraying Lord Ganesha (figure 1, right). The white undrilled, button-shaped pearl weighed 6.27 ct and measured 10.59 × 10.21 × 9.18 mm. Its surface was carefully carved to resemble the Indian deity, with the head of an elephant and the seated body of a man on the front and a swirling pattern on the back (figure 3). EDXRF analysis results showed a high manganese content of 598 ppm and relatively low strontium levels at 376 ppm. These readings were supported by a strong yellowish green fluorescence reaction when exposed to optical XRF (figure 4, left), indicating the pearl was from a freshwater environment. RTX imaging revealed the presence of a small twisted void, along with discoid-like features (figure 4, right) typically seen in non-bead cultured freshwater pearls (K. Scarratt et al., “Characteristics of nuclei in Chinese freshwater cultured pearls,” Summer 2000 G&G, pp. 98–109).
The transformation of pearls into valuable pieces of art is a specialized skill. Indian artists have mastered this ability and can transform pearls into symbolic pieces that have a special connection to ancient Indian scriptures. The laboratory staff at GIA in Mumbai continue to examine intriguing pearls of historical and cultural significance in India. @chapter:21


Publication Year: 2023 Title: Turquoise United Conference 2023 Abstract: Figure 1. From left: Jacob Lowry, Sean Hyrons, Matthew Wernz, and Kenneth Van Wey engage in a panel discussion titled “Laws: Liabilities and Protections.” Photo courtesy of the Turquoise Museum.
The second annual Turquoise United conference was held August 10–12, 2023, at the Albuquerque Convention Center in New Mexico. The vision of the conference is to bring together members of the turquoise industry at a single event for discussion and reunion. With this goal in mind, the conference caters to every aspect of the turquoise industry, attracting miners, lapidaries, collectors, dealers, artists, treatment experts, and researchers. A year ago, GIA representatives attended the inaugural Turquoise United conference (Fall 2022 GNI, pp. 390–394).
This year, there were additional symposium sessions across a range of topics and new competitions for registered conference participants. The first session was hosted by Turquoise Museum executive director Jacob Lowry, with a panel consisting of Kenneth Van Wey (Indian Arts and Crafts Board), Matthew Wernz (Federal Trade Commission), and Sean Hyrons (U.S. Fish and Wildlife Service). The panel discussed the laws surrounding the sale and purchase of turquoise jewelry and gave examples of situations in which their respective agencies may become involved (figure 1). The panelists offered advice to consumers purchasing turquoise jewelry, noting the importance of a written receipt stating the authenticity and nature of the product in as much detail as possible.
The turquoise grading system proposed by Joe Dan Lowry at last year’s conference has been put into practice. Attendees could attempt to grade sample stones or stones of their own using the system based on turquoise master stone sets and grades of color, matrix, and “zat” (boldness and dynamism). Application of the grading system requires detailed knowledge of certain turquoise features present at different mines. For example, author AG did not recognize “waterweb” matrix as being a valuable pattern, and therefore gave a lower matrix score on a stone with a high value. The grading system continues to be developed with feedback from the conference, with a goal of publicly accepted use by 2027.
The conference also offered courses for attendees. A “Turquoise Basics” course taught by Jacob Lowry described the types of turquoise and turquoise imitations in the market to better inform new buyers of the stone. Joe Dan Lowry taught a class called “Collecting 101,” offering guidance to consumers beginning their own turquoise collection. A follow-up course, “Collecting 102,” is planned for Turquoise United 2024.

Figure 2. Mark Baca (American Turquoise Online) holds his winning piece (right) and trophy for Best in Show. Photo courtesy of the Turquoise Museum.
Some attendees were rewarded for their impressive specimens and extensive turquoise knowledge. A highest-grade turquoise stone contest received numerous entries from multiple mines, ranging from natural cabochons with striking color and matrix to hefty rough turquoise nuggets. Best in Show winner Mark Baca (American Turquoise Online) received a monetary prize and trophy (figure 2). An identification contest over both days of the conference allowed attendees to test their skills at identifying the nature and mine origin of turquoise specimens. Michael Turano (Michael Turano Lapidary) won the contest, with Dye Masaki (Native Spirit) placing second, and Ty Gibson (Gibson Lapidary, LLC) in third.
Author AG presented his research on the Mona Lisa mine, located in western Arkansas, in a session on August 11. He provided details about the history, geology, mineralogy, and current mining operations at the site. Discussion about the methods used and Mona Lisa turquoise’s potential place in the market followed the presentation. Material from the mine was also on display at the Turquoise Museum, where the day ended with the Collectors’ Circle Gala.
The following morning, author AP presented GIA’s methods for identifying turquoise in the gemological laboratory. Attendees expressed their interest in learning more about these techniques and shared their views on terminology in the turquoise industry.
Next, Joe Dan Lowry presented a session on the challenges of fingerprinting turquoise mine sources, especially in archaeological contexts. The heterogeneity of turquoise, the multitude of sources, and the stone’s formation in near-surface, sedimentary environments create unique challenges when trying to determine a stone’s mine origin.

Figure 3. Left: A conference participant examines turquoise cabochons. Right: Iranian turquoise cabochon with a brown “spiderweb” matrix pattern. Photos by Aaron Palke.
Throughout the conference, a gem show focused solely on turquoise was open to the public. Roughly a dozen dealers participated, offering a wide variety of turquoise material (figure 3), including high-end jewelry pieces, natural rough material, untreated cabochons, stabilized cabochons, and beadwork. Many American turquoise localities were represented, while turquoise from Iran, China, Egypt, and Mexico was also available. A silent auction allowed conference attendees to bid on natural turquoise and turquoise jewelry pieces donated by the event sponsors.
The conference concluded with a banquet honoring the first inductees into the Turquoise Hall of Fame: Joseph Pogue, Leonard Hardy, Robert Zachary, Philip Chambless, and James Elquist. These honorees were nominated for their impact on the turquoise industry. The event sponsors reiterated their desire to grow Turquoise United, with confirmation that the annual event will be hosted in Albuquerque in 2024. @chapter:28


Publication Year: 2008 Title: Summer 2008 G&G Lab Notes Abstract: Diamond with Color Contributed by the 594 nm Center (?)
Subtle Flash-Effect Colors in a Filled Diamond
“Unidentified Clarity Characteristic” in Diamond
Gem-quality CVD Synthetic Diamond with Traces of Boron
Bleached Pinctada Margaritifera Cultured Pearls in Non-“Chocolate” Colors
Blue-Green Plagioclase Feldspar Possibly Colored by Copper
Unusual Green Fluid Inclusions in Quartz
Inclusions within Inclusions in Ruby
Blue Sapphire with Unusually High Concentration of Rare-Earth Elements

To view the full section, download the PDF above. @chapter:32


Publication Year: 2017 Title: Book Review: Gem Testing Techniques Abstract: By Alan Hodgkinson, hardcover, 552 pp., publ. by Valerie Hodgkinson, 2015, GBP185.

Although several books on gem testing have been previously published, this particularly comprehensive volume by renowned gemologist Alan Hodgkinson will certainly be a welcome addition to members of the field.  This book is geared towards a general audience from beginners to career gemologists. It is saturated with information, yet isn’t so technical to be impractical. The numerous chapters are organized in broad categories relating to particular physical properties. From acid testing of gem materials to the correct application of ultraviolet light, there is little that Hodgkinson does not cover. This book is well written with great detail. In its 552 pages, the reader will be pleased to find numerous images and diagrams that, while not generally glamorous, are very adequate for aiding the reader in understanding the concepts discussed. Scattered throughout the volume are a number of tips and tricks that the practicing gemologist may find useful to gain information while testing an unknown gem, such as using top lighting to observe pleochroism with a refractometer. Many of the methods require readily available and inexpensive materials, which many gemologists will appreciate; the use of “visual optics” to measure refractive indices with an elongate paper as an indexed scale is one example.

The book is clad in a plain blue hard cover, with silver lettering on the front cover and spine. A ribbon is included for marking one’s place as the reader navigates the pages. The overall quality of the paper, printing and binding appear to be very good. Overall, this book serves as a great reference for gemologists. The decades of experience by the author are apparent when reading through this book. Surely this will be a highly sought-after publication from which hobbyists and professional gemologists alike can benefit. @chapter:23


Publication Year: 2014 Title: Jadeite Bangle with the Appearance of Polymer Treatment Abstract: Figure 1. This 244.29 ct translucent light to deep green and brownish yellow bangle measures approximately 70 × 14 mm. It contained a transparent, light-colored area that suggested the possibility of a polymer impregnation process. Photo courtesy of Lai Tai-An Gem Lab.

Jadeite jade always comes under close scrutiny in the market because it is so frequently treated. The treatment options for jadeite jade are numerous: bleaching, dyeing, polymer impregnation, or a combination of these. Polymer impregnation is a particular favorite, a process that is not always easy to observe by magnification. A 244.29 ct translucent light to deep green and brownish yellow bangle measuring approximately 70 × 14 mm was recently submitted to the Lai Tai-An Gem Lab in Taipei. The client was concerned about a more transparent light-colored area (figure 1) that appeared to be possible evidence of impregnation.

Standard gemological testing indicated a spot RI reading of 1.54 at the more transparent light-colored area and 1.66 elsewhere on the bangle, an SG of approximately 3.32, and a characteristic jadeite spectrum exhibiting a band at about 437 nm. FTIR and Raman spectroscopy were also applied, producing spectral features that confirmed the bangle’s identity as jadeite jade. Microscopic examination revealed natural inclusions within the transparent area that appeared to be polycrystalline (figure 2). Neither would be seen in an impregnated specimen, ruling out this treatment. Further analysis with Raman microscopy was conducted to identify its true nature.

Sharp absorption peaks at around 207, 347, 400, 465, and 990 cm–1 were a match for nepheline (figure 3), a mineral sometimes associated with albite in jadeite. The nepheline crystal remained intact during the fashioning process, and its presence led to confusion over whether the bangle had been treated.

Figure 2. Microscopic examination of the suspect area revealed natural inclusions and a crystalline form. Neither would be found in an impregnated specimen. Photo courtesy of Lai Tai-An Gem Lab.

Figure 3. Sharp absorption peaks around 207, 347, 400, 465, and 990 cm–1 were consistent with nepheline, a mineral sometimes associated with albite in jadeite. @chapter:37


Publication Year: 2021 Title: Unique Metal Sulfide Inclusion in “Bing Piao” Red Agate from Liangshan, China Abstract: Figure 1. The cabochon on the left is a normal “Bing Piao” red agate measuring 12.50 × 19.60 × 10.11 mm. The bead on the right, approximately 11.80 mm in diameter, is a special type of “Bing Piao” red agate. Photo by Su Xu.

Over the past decade, with the discovery of “Nanhong” agate ore deposits in Sichuan Province, a significant amount of this material has been mined in Meigu County, located in the northeast of Liangshan Yi Autonomous Prefecture. Commercial gem mines in Meigu County are located in three main areas, including Jiu Kou, Wa Xi, and Lian He. Field observations show that the ore body is found either in the interlayer fissures and cavities of Permian Emeishan basalt crystallized from siliceous hydrothermal fluid or as conglomerates of the Permian Leping Formation.
Previous reports found that “Nanhong” agate is colored by natural hematite inclusions. Moreover, these agates are divided into five major categories, including “Bing Piao” (a Chinese term that refers to their inclusions “floating on ice”). This type of agate (see figure 1, left) is colorless and contains red hematite particles distributed in attractive patterns.
Recently, a special type of “Bing Piao” red agate called “black grass” agate by merchants appeared in the market at Liangshan. A bead of this material (figure 1, right) was obtained for examination at the National Gold-Silver Gem & Jewelry Quality Supervision & Inspection Center (Sichuan).

Figure 2. These antennae-like inclusions consist of dot-like black minerals, coupled with red inclusions. Photomicrograph by Xiaoping Shi; field of view 9.00 mm.
Gemological properties of the semitransparent bead, including its RI of 1.54 and hydrostatic SG of 2.65, suggested agate; this was confirmed by FTIR spectroscopy. Magnification revealed tiny red inclusions that were identified as hematite by Raman spectra (peaks at 225, 244, 291, 410, 610, and 1320 cm–1) using a 785 nm laser. In addition to these attractive red forms made of hematite, the bead hosted many unusual black mineral particles displaying various shapes such as blades, planar clusters, and the like (figure 2). When viewed with reflected light, microscopic observations of their opaque, anhedral form and metallic luster suggested the particles were likely an iron sulfide. A Raman spectrum obtained from a surface-reaching black particle showed two major peaks at 342 and 377 cm–1, matching well with pyrite, according to the RRUFF database (reference spectrum R100166), as shown in figure 3.

Figure 3. The black particle was identified as pyrite based on comparison with Raman reference spectra from the RRUFF database. Spectra are offset vertically for clarity.
To obtain confirmation, the bead was polished down to a plate to perform chemical analysis and phase identification of the black particles using a scanning electron microscope in combination with an energy-dispersive spectrometer (SEM-EDS) equipped with an electron backscatter diffraction (EBSD) detector. Qualitative analysis revealed the expected major elements of Fe, As, and S, along with minor Si, likely from the agate host. This was consistent with pyrite composition. The EBSD analyses indicated a cubic structure, and a search of the NIST Structural Database using Aztec software revealed a match for pyrite (FeS2).
Except for Liangshan, such distinctive black minerals of various forms have not been found in other “Bing Piao” red agate deposits. The pyrite particles, as inclusions that are unique to “Bing Piao” red agate from Liangshan, may therefore be considered reliable indicators of origin. Further gemological studies on these inclusions are required to construct the database for origin determination. @chapter:5


Publication Year: - Title: International Group Sets Sights on Sustainable Gemstone Mining Abstract: Artisanal miners at the Birim River near Akwatia, Ghana sift the gravels for diamonds. Photo by Russell Shor/GIA

The colored gemstone industry plays a tiny role on the world economic stage, but it has long been an important livelihood for hundreds of thousands of miners and traders in developing countries.
Improving those miners’ returns on their labor and their working conditions has been a difficult challenge, given the fragmented nature of the industry and the myriad conflicting interests at each trading level.
The Organization for Economic Cooperation and Development (OECD) held an important first-of-its-kind forum involving gemstone mining at its Paris headquarters in May to bring together as many actors in this scattered industry as possible. The goal of the three-day conference, that included a session on gemstone mining, was to begin the process of creating policies for sustainable mining practices and increasing returns for miners who often dig by hand with little to show for their efforts.
The OECD consists of 34 developed democracies with market economies that work with each other and some 70 non-member countries to promote economic growth and sustainable development. The organization estimates that 100 million people in more than 70 countries are engaged in artisanal and small-scale mining of a variety of minerals. About 15 million are mining for gold, including 4.5 million women and 600,000 children.
The forum, which included representatives of gold and other mineral interests in addition to colored stones, provided a platform for source country governments, gemstone traders, miners, civil society groups, large retailers and responsible source-certifying organizations to begin hammering out policies that will benefit producing nations and miners, while balancing the interests of other players.
Interviews with participants at the meeting illustrated the challenges of balancing everyone’s interests. For example:

Governments want revenue from and control of their resources, while miners resist regulations and export duties.
Artisanal miners – those digging with hand tools – often get very little from their finds partly because many of them operate illegally on private property or government-owned land and because they are often the poorest, most marginalized elements of society without education or power.
Large mining companies and fair trade certification agencies can adopt policies to promote sustainable mining and labor practices, and can afford the certification process. Small miners and dealers complain that such certification measures are too costly and are often used as an excuse to muscle them out.
Civil society groups and non-governmental organizations (NGOs) working with resources such as gemstones often insist on near airtight accountability for every gemstone mined, while miners and dealers claim this is an unrealistic, if not impossible, goal.
Retailers increasingly want supply chain accountability to counter customer concerns – real or potential – over sustainability and conflict issues. Miners and dealers in source countries, however, are often unaware of such consumer concerns or have different or conflicting priorities.

The OECD is working to balance all of these conflicting interests into its guidelines. The majority of attention to the artisanal mining sector focuses on bringing miners into the formal sector, which means legalizing their activities to help reduce their dependence on money launderers and corrupt officials who often extort money or other benefits from them in exchange for allowing them to continue mining illegally, said Estelle Levin-Nally, a consultant on mineral artisanal mining sustainability and previously director of the GIFF project.
Levin-Nally said governments are starting to come around on this issue. She added, however, that the “colored gemstone industry has, by and large, accepted the relevance of OECD guidance for responsible sourcing of minerals to their sector.” She said that this is a new development, adding that there are still large gaps to work through.
“Upstream (at the local dealer and mining level) there’s concern that the downstream people are pushing sustainability priorities like environmental protection or conflict financing, while also pushing for low prices,” she said. “On the other hand, in the producing countries, the miners, exporters and government officials are desperately seeking support to for their primary concern – maximizing revenues. This is the foundation for stimulating investment in handling the social and environmental issues.”
She acknowledged that realities at the mine sources “can be quite messy with crime, smuggling and control by corrupt elements. These are problems that still must be dealt with in many situations.” She emphasized the importance of commercial pragmatism and taking a “human rights based approach” to unleashing the economic potential of the sector.

Sustainability audits have created a divide between larger mining firms, such as Gemfield’s Kagem emerald mine in Zambia, and artisanal miners who claim they are disadvantaged because they cannot afford the lengthy certification process. Photo by Russell Shor/GIA

Governmental representatives at the meeting stressed the need to gain control over the mining of their resources before sustainable mining and fair labor practices could begin to operate. This means controlling mining and access to gem deposits; developing workable export procedures that bring in revenue, but do not invite smuggling; and excluding smugglers and criminal elements from mining areas.
While Levin-Nally notes that governments have been taking more initiatives in this direction, Jean Claude Michelou, a gemstone trader who has worked on these issues with the International Colored Stone Association, said the situation of many “informal” miners – those mining without permission from the government – remains very difficult.
“Many of these miners have no other means of support, so we need to find a way to legalize them,” he explained, adding that a number of countries continue to regard them as illegal squatters and operators.
Michelou, said some governments are now working to bring these miners into their legal framework.
“Colombia is one of the more involved governments in both its emerald and gold mining industries,” he said, because the government came to understand how much revenue it was losing by keeping these miners outside the system.
Myanmar, long an outlier because of sanctions against its military government, is also moving to wrest control of its ruby and jade production, Michelou said, adding that estimates of lost revenue shocked the country’s representatives at the meeting. Myanmar’s jade production is beset by huge challenges, noted in an earlier report.
While the OECD has developed an operational framework to account for all parties’ interests, the World Bank is starting to fund specific efforts to put these policies into practice through its Sustainable Management of Mineral Resources project.
Jeff Bilgore, who attended the meeting on behalf of the American Gem Trade Association, said his organization has developed a code of ethics and due diligence procedures over the past three years and its aim is to get these standards adopted by the OECD.
“Our prime concerns are to balance the miners’ interests with the concerns of small family businesses in producer nations and consumers in the U.S,” he said. “There’s been a lot of progress, but it’s step-by-step. Things are still far from perfect, but we are moving forward.” @chapter:38


Publication Year: 2023 Title: Glass Imitation of Cat’s-Eye Chrysoberyl Abstract: Figure 1. A ring mounted with an estimated 5.56 ct brownish yellow cat’s-eye cabochon resembling chrysoberyl. Photo by Johnny (Chak Wan) Leung.
The Hong Kong laboratory recently examined a ring mounted with an estimated 5.56 ct brownish yellow cat’s-eye cabochon (figure 1). The client submitted the stone as cat’s-eye chrysoberyl, which it resembled at first glance. Standard gemological testing yielded a spot refractive index of 1.57, well below chrysoberyl’s range of 1.74–1.75. Under short-wave UV radiation, the stone displayed strong chalky fluorescence. Microscopic observation revealed long parallel tubes creating a cat’s-eye when viewed from the top and a honeycomb structure when viewed from the side of the stone (figure 2). This confirmed the material was fiber-optic glass, made by fusing together very thinly spun glass fibers. Infrared spectroscopy showed two broad absorptions centered at 3500 and 2670 cm–1 associated with artificial glass, further validating our identification.

Figure 2. The cabochon displayed the honeycomb structure frequently observed in fiber-optic glass. Photomicrograph by Tsz Ying Fong; field of view 2.00 mm.
Artificial glass has been used as an imitation for different gems such as star sapphire (Fall 2021 Lab Notes, pp. 261–262), Paraíba tourmaline (Winter 2020 Lab Notes, pp. 518–520), nephrite and jadeite (Spring 2019 Lab Notes, pp. 93–94), and blue amber (Fall 2019 Gem News International, pp. 443–444). Its color and appearance can often lead to misidentification. Therefore, conducting basic gemological tests and observing the stone under a microscope is important, especially when the stone is set in jewelry. @chapter:19


Publication Year: - Title: Pearl Journey Abstract: Few people outside the gem industry realize the true nature of a cultured pearl’s journey from the producer 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.  Careful nurturing, countless hours of labor, and significant investment are needed to being a pearl to market. @chapter:33


Publication Year: 2014 Title: Books: Jewels of the Romanovs: Family & Court Abstract: By Stefano Papi, 352 pp., hardcover, illus. publ. by Thames & Hudson, 2013, $75.00.

              Stefano Papi’s Jewels of the Romanovs: Family & Court is a study of the Russian dynasty’s jewels and its gilded world at the turn of the 20th century. In this second edition, published to commemorate the 400th anniversary of the Romanov empire, Papi examines a wide range of items, from the crown jewels to intimate personal gifts made by court jeweler Carl Fabergé. Papi specializes in European jewelry and has worked for both Sotheby’s and Christie’s as a jewelry specialist; his expertise in the field of historical jewelry, plus his gemological background, make for fascinating reading.

For the reader who enjoys the history of Imperial Russia, this book offers a rich treasure trove of archival photos of the Romanovs and members of their court. The photos show not only the formal life of the royals but also intimate everyday scenes, giving a glimpse into the personalities behind the titles. Papi delves into the unique people who populated the royal circles, as well as the artists whose work adorned them. This book gives the reader an intimate look into the lives and personalities of early 20th century Europe. Navigating the family tree of European royal houses is no easy task, but Papi does a fine job of connecting the dots as he introduces the various characters. The history buff will enjoy both the images and the unique, colorful stories the author weaves.

For those interested in gems, this book offers archival and modern photos of some of the most beautiful and impressive jewels ever created. These are supplemented with compelling descriptions and stories of the jewelry’s provenance. The reader is taken on an incredible journey of intrigue and romance that crosses the globe and includes such stones as the 189.62 ct Orlov diamond in the Imperial Scepter, as well as the 400 ct spinel in the Great Imperial Crown. Pieces of jewelry are often accompanied by an archival photo or painting of the owner wearing the piece. Included in this volume is a beautiful color photo of a kokoshnik, or traditional Russian headdress, made with diamonds and large cabochon emeralds by the court jeweler Bolin. A black-and-white photo shows Queen Marie of Serbia wearing it, along with diamond earrings weighing 20 carats each. Over the years, some pieces have been lost or broken up to make other pieces, so these illustrations serve as a historical record.

The book is illustrated with masterpieces by the greatest jewelers of the time: Cartier, Bolin, Boucheron, Chaumet, Lalique, and, of course, the venerable Fabergé. They all catered to the courtiers of St. Petersburg. One of the prominent personalities at court was Maria Pavlovna, the Grand Duchess Vladimir. Married to Grand Duke Vladimir, brother of Alexander III, she was known for her collection of magnificent jewels. There was not one prominent jewelry house in St. Petersburg, Paris, or London that did not know her. She was one of their most important clients, famous for her glorious balls and dinner parties that rivaled even those at the Imperial court.

During the Russian Revolution, Empress Alexandra managed to get her major jewels out of the country. Some smaller treasures, including Fabergé cigarette cases and her husband’s cuff links, were stuffed into pillowcases and smuggled by a friend to the Swedish embassy. They remained stored in the basement of a government building in Stockholm until they were discovered in 2009. Sotheby’s sold off this treasure trove, along with the two pillowcases, in November of that year. One of the book’s more memorable photos shows several of the Fabergé cigarette cases on top of the pillowcases. This adventure is just one of many that enhance the history of the jewels in this book.

Of course, the story of the Romanovs ended tragically. Papi devotes the final two chapters to the last days of the royal family, documented in photos, and the final dispersal of royal treasures by the Bolsheviks. Many pieces made their way into American collections through dealers such as Wartski in London and Armand Hammer in New York. If only these jewels could speak, what stories they might tell! Stefano Papi has created a well-researched, beautifully illustrated book that gives them voice. @chapter:21


Publication Year: 2018 Title: Three Irradiated CVD Synthetic Diamonds Abstract: Figure 1. These 1.12 ct, 1.14 ct, and 1.34 ct laboratory-irradiated CVD synthetic diamonds all have similar appearance, with color grades equivalent to Fancy Deep green-blue. Photos by Robison McMurtry.
While laboratory-irradiated diamonds are often submitted for grading reports, irradiated synthetics with a green-to-blue color are still a rare occurrence. Before the submissions described here, GIA’s laboratory had examined only three irradiated CVD synthetics (Fall 2014 Lab Notes, pp. 240–241; Fall 2015 Lab Notes, pp. 320–321) and two irradiated HPHT synthetics. So it was interesting when the Carlsbad laboratory received three irradiated CVD synthetics, apparently from the same client.
All three synthetics showed very similar features in terms of color (equivalent to Fancy Deep green-blue; figure 1), clarity (equivalent to VVS2), and weight (1.12 ct, 1.14 ct, and 1.34 ct), along with comparable features detected by fluorescence imaging (figure 2) and spectroscopy (figure 3).

Figure 2. All three irradiated CVD synthetics displayed very weak fluorescence in the DiamondView, as seen in the 1.14 ct sample shown here. All showed the characteristic striations of CVD growth. Image by Sally Eaton-Magaña.

Figure 3. Radiation-related features dominate the CVD synthetic diamonds’ Vis-NIR absorption spectra when collected at liquid nitrogen temperature. Features include the GR1 at 741.2 nm, the 595 nm center at 594.2 nm, the TR12 center at 469.9 nm, a radiation-related peak at 464.3 nm, and the GR2 at 429 nm.
The Vis-NIR and IR absorption spectroscopy and the photoluminescence (PL) spectroscopy were nearly identical among the three specimens, indicating that they were probably grown and treated under similar if not identical conditions. The IR absorption spectra showed very weak 3107 cm–1 and 1344 cm–1 peaks. Based on the integrated area of the 1344 cm–1 peaks (I. Kiflawi et al., “Infrared absorption by the single nitrogen and A defect centres in diamond,” Philosophical Magazine B, Vol. 69, No. 6, 1994, pp. 1141–1147), we determined the single N concentration as about 0.4–0.5 ppm for all three samples. The Vis-NIR absorption spectra showed typical features for irradiated diamonds: the TR12 (a radiation-related feature tentatively ascribed to a divacancy/di-interstitial defect at 469.9 nm), the 595 nm center, and GR1 [V0] at 741.2 nm (figure 3). PL spectra showed a weak SiV– doublet at 736.6 and 736.9 nm along with a very strong GR1 center. PL spectroscopy also indicated the presence of the H2 peak at 986.2 nm and the lack of the 596/597 nm doublet that is normally seen in as-grown CVD synthetics and generally disappears with post-growth treatment. This combination, along with the 3107 cm–1 peak in the IR spectra, suggests these diamonds were HPHT treated before irradiation.
Owing to their extreme rarity and individuality, creating a set of matching natural-color diamonds can be quite challenging. In contrast, synthetic diamonds can demonstrate uniformity in features and appearance due to the manufacturer’s ability to control the growth conditions, defect concentrations, and the subsequent treatment parameters. @chapter:15


Publication Year: 2020 Title: New Emerald Locality in Southern California Abstract: Figure 1. A map of California with an inset showing the San Diego area and marking the emerald locality (star).
Located about 60 miles east of San Diego, a new emerald deposit has been discovered in the Julian Mining District (figure 1). This area is known for pegmatite mines and hydrothermal mineral deposits; however, none of those are known to have produced emeralds to date. The emeralds (example shown in figure 2) were all collected by author RE and son Bruce Edley near the surface and are embedded in a biotite schist host rock. Most of the recovered single crystals have a translucent dark green color and inclusions, and they are typically smaller than 2 cm. A few light-colored green beryl crystals have been recovered from a nearby pegmatite. Their formation was likely correlated with metamorphic and hydrothermal processes associated with regional tectonism.

Figure 2. An example of an emerald cluster found in a new deposit in Julian, California. Specimen size is 20 × 10 × 9 mm. Photo by Myke Clarkson.
Samples were analyzed at the Natural History Museum of Los Angeles County and sent to GIA for species confirmation using laser ablation–inductively coupled plasma–mass spectroscopy (LA-ICP-MS). We performed Raman and X-ray fluorescence (XRF) hyperspectral mapping and powder X-ray diffraction (not shown) to determine mineralogy and elemental composition. Raman analysis on a polished pill-shaped gem (figure 3, left) identified beryl and quartz to confirm our observation of the rare combination of emerald and citrine. Raman further identified dolomite and hematite inclusions. XRF element maps (figure 3, right) show silicon (Si), chromium (Cr), magnesium (Mg), iron (Fe), aluminum (Al), and holmium (Ho) content. Of the approximately 425 carats of emeralds that have been recovered, about 5–10% contain macro-citrine inclusions, representing a unique aspect of this deposit.

Figure 3. Left: A 3.16 ct polished pill-shaped emerald, seen in transmitted light, was one of the best examples of emerald with citrine from this locality. Photo by Aaron Celestian. Right: Element maps of the outlined area on the specimen. Brighter areas indicate higher concentrations.
The distribution of trace elements in the pill-shaped emerald indicates a complex series of events. The emerald is cross-cut by a layer of citrine. Half of the gem is enriched in trace holmium (below the citrine), where holmium is inversely correlated with manganese. Chromium-rich areas run perpendicular to the citrine, but align on either side of the citrine, suggesting that the emerald formed as a single crystal. The patterns of holmium and manganese hint toward secondary geochemical processes that may be related to later citrine emplacement, though the origin of these processes is unknown. The unusual mineral associations and elemental distribution demonstrate the geologic complexity of the deposit, and further work is needed to unravel its full history. @chapter:8


Publication Year: 2013 Title: Exotic Stingray Skin Jewelry Abstract: Figure 1. This piece of stingray jewelry is placed on a backdrop of stingray skin. Courtesy of the Ferraccia Jewelry Collection. Photo by Eric Welch.

              Leather has long been used in jewelry, combined with precious metals and gemstones to add a special flavor. The variety of textures from different animal skins offers a highly versatile component for designers.

The Ferraccia Jewelry Collection exhibited a huge variety of stingray leather goods at the AGTA show, including bracelets (figure 1), necklaces, earrings, rings, belts, purses, and mobile phone cases. Stingray is not considered an endangered species. They are harvested as a delicacy in Asia and some Eastern European countries. The leather used in this collection comes only from the top of the stingray. This part of the skin, which serves as the animal’s armor and backbone, rarely exceeds 10 inches wide and 17 inches long (figure 2). The polished stingray skin displays a unique texture resembling hundreds of sparkling pearl-like spots under proper lighting. This pattern is tactile as well as visual. Considerable effort went into the tanning and finishing process to obtain the deep color and durability. Thirty custom dyed colors were created, and each skin has its own pattern, adding to the uniqueness and exotic appeal.

	Figure 2. A close-up view of the processed stingray skin shows numerous shiny pearl-like spots. Courtesy of the Ferraccia Jewelry Collection. Photo by Eric Welch.
Stingray leather is also very durable because the tiny grains are all rooted in the underside of the skin. With proper care, it should last more than a lifetime. A damp cloth, air drying, clear leather polish, and mild soap are used to remove any remnants between the individual grains. @chapter:14


Publication Year: - Title: Thai Designers Draw Inspiration from Tradition, Heritage for Jewelry Contest Abstract: View Gallery

Fresh. Exciting. Innovative.

	These are just a few words used to describe the nearly 300 designs submitted to the “Create Your Own Legacy” jewelry design challenge hosted by GIA in Bangkok.

	The contest, which opened mid-2013, encouraged designers of all experience levels to be inspired by the cultural legacy of Thailand. The result? A bounty of jewelry sketches inspired by native flowers, mangrove trees and other symbols of Thailand as varied as the designers who created them – from college students and jewelry enthusiasts to jewelry professionals.

	The five-month process – organized to commemorate the 20-year anniversary of GIA in Bangkok – was an opportunity for Thai designers to showcase their talent, expand their gemological knowledge and work alongside prominent jewelry companies Beauty Gems, Blue River, Fadamas, Mouawad and Sette. The finalists were also awarded prizes and scholarships for GIA design, gemology and jewelry programs. The first place designer earned a scholarship for the on-campus Graduate Gemologist program and a trip to the Hong Kong International Jewellery and Gem Show in March 2014.

	“The Bangkok community has been a gracious and hospitable host to GIA for 20 years. This contest was an opportunity to give something back to the jewelry industry here,” said Kenneth Scarratt, GIA managing director of South East Asia and director of the laboratory in Bangkok.

	Entries were reviewed by a panel of judges that included industry experts and respected members of the community. The group selected 21 designers to advance to the next step of the contest: an intensive gemological workshop at the Bangkok campus specifically created to further develop the participants’ knowledge of diamonds and gemstones, as well as to strengthen their design capabilities.

	Participants at the three-day gemological workshop at the GIA campus in Bangkok show their design sketches. Photos by GIA

	Finalist Songsak Sirimartpornchai of Bangkok, a jewelry designer with more than 18 years of experience, said the workshop helped him learn more about the types of gems to select for his jewelry pieces. “I will use the knowledge I learned in this class for future designs as well,” he said.

	Once they completed the workshop, the designers were asked to either develop their original work further or submit a new sketch for the next round of judging, taking care to incorporate colored gemstones in their designs.

	Another finalist, Sutattar Chanrungrojne, from Ayutthaya, Thailand, designed a necklace, cuff and earring set inspired by a practical baking tool.

	“People often find inspiration from beautiful objects, but I wanted to think differently,” she said. “Banana leaves, which don’t always look appealing, are very useful in the traditional Thai way of life. They are often used for baking food and desserts instead of tinfoil or parchment papers.”

	Sutattar Chanrungrojne was inspired by banana leaves when she designed “Baitong,” a necklace, cuff bracelet and earring set. Contestants worked with jewelry companies to manufacture their designs (left) into tangible jewelry pieces.

	Her sketch, which features vibrant green gems, was chosen as one of the top five designs.

	The five finalists had the opportunity to work directly with jewelry companies to manufacture their designs into finished pieces that were then reviewed by the judging panel. The winner’s designs were announced at a presentation ceremony at the Bangkok Art and Culture Center in late 2013.

	The first place winner, Nattawat Srinoon, of Nakhon sri thammarat, Thailand, designed pieces inspired by traditional Thai textiles. His jewelry, titled “You Clothe Me,” represents the history and legacy of Thai culture. A student majoring in jewelry design at Silpakorn University, he plans to further his studies in fashion design after completing the Graduate Gemologist diploma.

	First place winner Nattawat Srinoon designed “You Clothe Me,” a suite of jewelry pieces inspired by traditional Thai clothing.

	“I believe that jewelry and fashion are inseparable,” he said.

	He said it is rare to find jewelry contests specifically targeted to Thai designers, especially ones supported by leading jewelry companies. “I learned a lot from the intensive gemological workshop, and also gained more experience in manufacturing by working with the jewelry companies.”

	But it wasn’t only the contestants who benefitted from the event.

	“Contestants had the opportunity to have their designs reviewed by industry professionals and design experts and each contestant gained experience to move forward in their gem and jewelry career,” GIA’s Scarratt said. “But the participating jewelry companies also had a great opportunity to work with new talent and be inspired by the creative designs.” @chapter:16


Publication Year: 1985 Title: Spring 1985 G&G Lab Notes Abstract: Heat Treated Amethyst
Garnet Almandite, Exhibiting both Chatoyancy and Asterism
Massive Grossularite Garnet Carving
Damaged Mabe Pearls
Pearl Simulants, Shell Hinges
Multi-Star Quartz
Ruby with Unusual Inclusions
Sapphire Simulant, Synthetic Green Spinel and Synthetic Blue Sapphire Doublet
Turquoise Simulant, Dyed Magnesite

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


Publication Year: 2023 Title: A Traditional Bombay Pearl Bunch Abstract: Figure 1. A Bombay bunch consisting of nine hanks and 553 high-quality natural pearls ranging from 3.83 to 5.72 mm. Photo by Gaurav Bera.
During the era when the maharajahs and maharanis ruled much of India, natural pearls were in great demand. In the nineteenth and early twentieth centuries, many merchants from the Middle East relocated to Bombay (now Mumbai) to benefit from this demand (R. Carter, Sea of Pearls, Arabian Publishing, London, 2012, pp. 169–175). Thus, it is no surprise that India has been a significant center of pearl manufacturing, processing, and trading for centuries. To showcase their high-quality pearls, traders and artisans in Bombay would sort the pearls, string them with silk threads, and tie them together at both ends using decorative metallic cords of various colors. These bunches were in great demand in the heyday of the natural pearl market and were sold as “Bombay bunches” (M. Manutchehr-Danai, Dictionary of Gems and Gemology, Springer, Berlin and Heidelberg, 2008, p. 101).
Recently, GIA’s Mumbai laboratory had the opportunity to examine an 80-year-old Bombay bunch inherited by one of the city’s established pearl families. The bunch consisted of 553 light cream round and near-round drilled pearls, strung in nine hanks, each containing four strands, with the exception of one hank with seven strands. The hanks were tied at both ends with white metal wires, together with silver and blue cords and tassels (figure 1). The pearls ranged from 3.83 to 5.72 mm, and the total weight of the bunch was approximately 80.51 g. The owner stated that the total weight of the pearls was approximately 130 chow (equivalent to 331.8 ct or 66.35 g). Chow is a system of converting weight into volume (The Pearl Blue Book, CIBJO, 2020).

Figure 2. Real-time microradiography images of eight pearls from the Bombay bunch revealing fine growth arcs and concentric ringed structures typical of those internal structures observed in Pinctada radiata pearls.
The strung pearls were perfectly matched in color and exhibited smooth surfaces with high luster. When viewed under 40× magnification, they all exhibited typical nacreous overlapping aragonite platelets. Their internal structures were examined by real-time microradiography. The majority revealed fine growth arcs and concentric ringed structures, while others revealed tight or minimal structures, some with small faint cores or light organic-rich cores (figure 2). It was evident that these were natural pearls from Pinctada-species mollusks, as their internal structures were very similar to those observed in Pinctada radiata pearls from the Arabian (Persian) Gulf when compared to GIA’s research database.
All pearls showed an inert reaction when exposed to optical X-ray fluorescence analysis. Energy-dispersive X-ray fluorescence spectrometry on a few samples revealed manganese values ranging from below detection limits to 30.7 ppm and strontium values of 1215 to 1989 ppm, consistent with a saltwater growth environment. Raman analysis using 514 nm excitation was also carried out on the surface of selected pearls showing a doublet at 702/705 cm–1 as well as a peak at 1085 cm–1, indicative of aragonite. Very weak polyenic pigment-related peaks at 1130 and 1530 cm–1 were also observed in a few of the pearls, likely associated with their light cream coloration (A. Al-Alawi et al., “Saltwater cultured pearls from Pinctada radiata in Abu Dhabi (United Arab Emirates),” Journal of Gemmology, Vol. 37, No. 2, 2020, pp. 164–179). The photoluminescence spectra under 514 nm excitation were also consistent with the Raman results and displayed high fluorescence together with the aragonite peaks, typical of most nacreous pearls. When exposed to long-wave ultraviolet light, the pearls showed a moderate blue reaction.
Historically, Bombay bunches were known to contain high-quality Pinctada radiata pearls fished from the Arabian (Persian) Gulf, commonly referred to as “Basra pearls” in the trade. Records indicate that the proportion of round pearls found in each natural pearl harvest today is less than 5% (H. Bari and D. Lam, Pearls, Skira, Milan, 2010, p. 43). Natural pearls are rare to find, and it can take decades to match a round pair of similar size, color, and luster. Encountering Bombay bunches in today’s market is a rarity, and it was a great opportunity for GIA Mumbai to examine such an interesting and memorable pearl submission. @chapter:14


Publication Year: 2024 Title: CVD with “Ancient Text” Clouds Abstract: Figure 1. The pavilion of this 1.67 ct pear-shaped CVD-grown diamond displayed an interesting feature with numerous cloud features resembling lines of text. Photomicrograph by Raju Jain; field of view ~2 mm.
The Surat lab received a 1.67 ct D-color pear shape submitted for laboratory-grown diamond service. Spectroscopy and fluorescence imaging confirmed this was a diamond grown by chemical vapor deposition (CVD) that had undergone post-growth high-pressure, high-temperature (HPHT) annealing. This CVD diamond with SI1 clarity displayed an interesting cloud feature that resembled lines of text in an ancient manuscript (figure 1).

Figure 2. A DiamondView image of the pavilion shows the region containing the cloud characteristic. While this image reveals the growth interfaces and the coloration confirms HPHT annealing, it does not show features corresponding to the cloud. Image by Suvarna Gaikwad.
The “lines” of clouds—a feature never before seen by the authors—were oriented approximately 45° to the growth interface seen with DiamondView imaging (figure 2). Examination of the fluorescence images (including those collected with selective-wavelength filters) revealed that the cloud features did not coincide with dislocation bundles, and striations were not observed. Photoluminescence mapping with 532 nm excitation showed high concentrations of the silicon vacancy (SiV–) defect at 737 nm but did not indicate any spatial features corresponding to the clouds. Infrared absorption spectroscopy indicated a type IIb diamond with very low concentrations of uncompensated boron.
This diamond was noteworthy for its unusual and visually appealing clarity characteristic. Additionally, the dichotomy of a thoroughly modern diamond with a cloud feature that evoked an ancient text provided an interesting submission. @chapter:15


Publication Year: 2022 Title: Apatite Oiling: Before and After Abstract: Figure 1. Left: On the base of this apatite cabochon (15 × 15 × 13 mm), a large, reflective fissure can be observed with fiber-optic illumination. Right: After the oil filling, the same fissure is much less noticeable and the iridescent reflective area is considerably smaller, enhancing the sample’s clarity. Photos by E. Billie Hughes.
Fissure filling of gemstones is an age-old treatment that can improve a stone’s clarity (Fall 2020 Gem News International, pp. 443–444). By introducing oil or other fillers such as resin into the stone, the treater can minimize the appearance of fissures.
Recently we had the opportunity to observe this treatment up close in an apatite cabochon brought to our laboratory for photography while it was still untreated. Then the sample was oiled by Jeffery Bergman and returned to the laboratory for observation and photography.
Upon examination before and after, the effects of the treatment were clear. On the base of the cabochon, a large, reflective fissure became less visible after oiling (figure 1). Using fiber-optic illumination, it was apparent that the filler had diminished the reflective appearance of the fissure, with only small highly reflective areas remaining (figure 2). Darkfield illumination also revealed a stark difference in appearance: The filler had rendered large dark areas filled with air nearly invisible (figure 3).

Figure 2. A close-up of the fissure before and after oil treatment, shown in diffuse fiber-optic illumination. Left: Before oiling, the fissure is easily visible and highly reflective. Right: After oiling, the reflection is more muted and less noticeable, with only a small highly reflective area remaining. Photomicrographs by E. Billie Hughes; field of view 10 mm.

Figure 3. Left: Before filling, transmitted light shows dark areas where air has become trapped in the fissure, making it more visible. Right: Treatment with oil minimizes the dark areas, enhancing clarity. Photomicrographs by E. Billie Hughes; field of view 27 mm.
This microscopic observation serves as a reminder of the significant impact clarity enhancement can have on gems of all types. @chapter:8


Publication Year: - Title: Internet Jewelry Pioneer Creates ‘Gems of Madagascar’ to Improve Lives of Children Abstract: Michelle Rahm, GG, founded "Gems of Madagascar" in 2015 to help provide clean water projects and other basic needs for the nation’s children. Here, she is pictured with three girls from the village of Mananjara, whom the organization sent to school because their families could not afford to. “They were so happy and doing well in their studies, and their dispositions had changed so much,” she says. “It’s amazing how much something like sending the girls to school changed their overall well-being.” Courtesy of Michelle Rahm

	Michelle Rahm is many things: an accomplished business owner, a seasoned gemologist, an Internet jewelry sales pioneer and an award-winning leader in the GIA Alumni Association.

	But when Rahm visited Madagascar in 2014 to learn about its mineralogy and tour mining localities, she didn’t expect to also become an advocate for the nation’s children. “I never imagined that a business trip to Madagascar would change my life,” she says.

	Rahm’s business began when she decided “on a whim” to put a few pieces of costume jewelry for sale online in 1997. “It was an experiment to earn a little extra money for Christmas while my other start-up business was in the works,” says the Colorado resident. “But the jewelry sold so well right away, I never went back to the other business.”

	She tried wholesaling items like hot cocoa and coffee, but jewelry and watches always performed best, so she zeroed in and founded JewelryImpressions.com.

Michelle Rahm, president of the GIA Alumni Association’s Mile-High Chapter, used her expertise as a pioneer in online jewelry sales to help her alma mater develop an e-commerce curriculum. Courtesy of Michelle Rahm

	As Rahm found success in online jewelry sales, though, so did others.

	“The Internet was becoming more accepted as a means of commerce, and I wanted an edge over my competition by having real credentials in the trade,” she says. When Rahm found herself at the Jewelers 24 Karat Club golf tournament with Douglas Hucker, CEO of the American Gem Trade Association, she asked his opinion on whether she should pursue her Graduate Gemologist diploma.

	“He strongly encouraged me to do so,” says Rahm, a graduate of the University of Wisconsin - Platteville. “Within six months I signed up for classes, and had finished the program a year later.”

	Rahm soon noticed the effects of a GIA education on her business: as her knowledge increased, her sales evolved from costume jewelry to fine jewelry and loose stones – and she was able to communicate with customers in an entirely new way.

	“My GIA education allowed me to speak intelligently about gems and diamonds to my clients,” she says. “There is a trust factor there that consumers don’t find with other retailers who do not have their GG. I feel like my diploma helps me stand out in the sea of jewelry retailers, especially those selling on the Internet. When I have the opportunity to speak to customers, they realize that I have the education to back what I say.”

	Rahm continued to engage with customers, seizing an opportunity in 2009 when she recognized that many of them were buying loose stones to be set in engagement rings. She created OurCustomWeddingRings.com, which sells engagement rings set with colored stones.

Michelle Rahm’s June 2014 trip to Madagascar’s mining localities was inspirational for its continuing education opportunities and connection to her GIA studies. “The most exciting destination for me was the Ilakaka alluvial sapphire deposit (pictured here), because I saw a video about it in my GIA coursework,” she says. Photo by Jaroslav Hrysl/Courtesy of Michelle Rahm

	She also threw herself into involvement with the GIA Alumni Association – she’s president of the Denver, Colorado-area Mile-High chapter – and into continuing education classes and workshops. It was her quest for ever-expanding knowledge that led Rahm to that life-changing trip to Madagascar, where she was thrilled to visit sites like the Ilakaka alluvial sapphire deposit she studied in her GIA coursework.

	What impacted her the most, though, was a surprise. “It wasn’t the sparkling gems that caught my eye,” she says. “It was the children.”

	Rahm felt an instant bond with the “beautiful” children she met with such “rich spirits,” but was overwhelmed by their lack of access to clean water, nutritious food and other fundamental necessities for survival. She returned to the United States with a resolve to learn about clean water projects and other basic needs of the Malagasy people.

	The real “gems” of that nation, she says, are its children. She joined forces with partners in Madagascar and Colorado and founded GemsofMadagascar.org, a non-governmental organization with a “holistic approach” to humanitarian work. The nonprofit, which was officially created in 2015, will offer first aid and hygiene training, develop community gardens and clean water systems, and construct buildings, among other needs that will give local children a better chance of a bright future. The first two projects will launch this summer: a clean-water system that will supply eight villages, and a church and community building for another village. There are plans for more clean-water systems in the next year.

	Rahm has traveled back to Madagascar several times in the last couple of years. In addition to her work with her own business and as a leader in the Alumni Association, Rahm is thrilled at the many opportunities and paths that have developed from a “whim” of a decision to sell some costume jewelry online.

	“I absolutely love my career,” she says. @chapter:33


Publication Year: 2024 Title: Guatemalan Jadeite Jade: Rough and Finished Abstract: Figure 1. The rough Guatemalan jadeite jade sold by Yax Tun Minerals included blue, green, and lavender hues, with blue being the most prevalent. Photo by Tao Hsu; courtesy of Yax Tun Minerals.
Jadeite jade is one of the most important aggregate gems in today’s global marketplace, with known sources in Myanmar, Japan, Russia, and Guatemala. Among them, Myanmar is the most legendary and still dominates today’s market. Guatemala, however, has recently reclaimed its status as an important jadeite jade producer (see Z. Huang et al., “‘Ice jade’ from Guatemala,” pp. 26–41 of this issue).
At this year’s 22nd Street show, Yax Tun Minerals (Denver, Colorado) offered a wide range of Guatemalan jadeite jade, including rough pieces in blue, green, and lavender (figure 1). According to owner Luke Miller, the bluish color is the most common and the most desired in the American market. All rough is covered with a “skin” resulting from weathering.

Figure 2. The bluish jadeite jade from Guatemala showed high transparency and a very fine texture (left). Some displayed green veins throughout. A flashlight revealed a slight green tint in some pieces with high transparency and fine texture (right). Photos by Tao Hsu; courtesy of Yax Tun Minerals.
The seller provided a strong flashlight for buyers to assess the quality of the rough, similar to what buyers do at the major jadeite auction in Myanmar. The blue color was quite saturated, while the green and lavender colors were not. The bluish rough showed high transparency and some had green veins running through it (figure 2, left). The green veins also exhibited high transparency (figure 2, right). The lavender rough pieces were of low transparency and had a coarser texture than the other two color varieties (figure 1).
The blue color is characteristic of Guatemalan jadeite jade, which is often called “Olmec blue” in the trade. The Olmec civilization was a Mesoamerican culture revealed by archaeological artifacts. The blue to green-blue jadeite jade mined in Guatemala was prized by the Olmecs from about 1500 to 400 BCE. Mesoamerican cultures that followed, such as Mayan, Zapotec, and Totonac, continued the reverence for jadeite jade. But when the Spanish conquered Mesoamerica in the sixteenth century, their appetite for gold and emeralds contributed to the fall of Guatemalan jadeite jade popularity. Mayan guards kept the jade mine locations secret, and they were not rediscovered until 1974. Since then, Guatemala has been gradually regaining recognition as an important source of jadeite jade.
Finished products offered at the Yax Tun booth included beads, beaded necklaces, bracelets, earrings, and small pendants, polished or carved. Many of the top-quality materials are processed at Miller’s carving studio in Mexico.

Figure 3. This spectacular “Rainbow Luna” dagger features a blade of beautiful Guatemalan jadeite jade that shows the characteristic Olmec blue color and even deeper purplish blue close to the point. Courtesy of Georg Schmerholz.
As Guatemalan jadeite jade gains popularity among both Western and Asian consumers, more gem artists are using this material to show their creativity. World-renowned sculptor Georg Schmerholz brought an outstanding collection of jade to the Tucson Gem and Mineral Show. His latest creation, “Rainbow Luna,” is second in the “Resplendent Quetzal” series, which honors a beautiful bird native to Guatemala. Completed in June 2023, the 14-inch dagger is carved from the finest Guatemalan jadeite jade with a patinated bronze handle (figure 3). Schmerholz’s jade art bridges the two disciplines of sculpture and gemstone carving.
The wide range of appearance and quality of Guatemalan jadeite jade offers versatility to designers, artists, and consumers. Sufficient production and distribution are essential for this gem material to reach a wider audience. @chapter:37


Publication Year: 2015 Title: Cleavage System in Pink Diamond Abstract: Figure 1. This Fancy Intense purplish pink 0.29 ct diamond was host to a complex cleavage network. Photo by Robison McMurtry.

	A 0.29 ct natural Fancy Intense purplish pink diamond with a microscopically interesting geometric feature (figure 1) was recently examined at GIA’s Carlsbad laboratory. A network of planar cracks, oriented in three octahedral directions, was observed at the surface of a pavilion facet (figure 2). These linear cleavage cracks were caused by localized strain on an octahedral plane.

Figure 2. Three directions of cleavage along octahedral planes are seen in this pink diamond. Photomicrograph by Jonathan Muyal; field of view 1.22 mm.

	The octahedral plane in diamond has the weakest atomic bonding, which means that when a diamond is strained, this is the direction that will be most affected. This stone offers the perfect example of strain products in pink diamond. The purplish pink color results from plastic deformation along octahedral planes. Also present along the octahedral plane is a zone where the strain was so great that it was relieved by cracking, creating the cleavage network seen in figures 2 and 3.

Figure 3. Between crossed polars the diamond shows high-order interference colors consistent with the strain causing the cleavage network along the octahedral planes. Photomicrograph by Jonathan Muyal; field of view 0.62 mm.

	The cleavage network in this diamond is the most aesthetic one encountered by the author to date due to its finely textured geometric pattern. Interestingly, the clue to the planar cleavage network lies in the bodycolor of the stone, which indicates significant strain. This high-order strain is easily revealed between crossed polars. If a cleavage network is present in a diamond such as this, it may have a strain-induced bodycolor as well. @chapter:11


Publication Year: 2020 Title: Solid Carved Dark Gray Diamond Ring Abstract: Figure 1. This carved Fancy Dark gray diamond ring weighs 13.15 ct. The whitish areas are clear viewing windows. Photo by Jianxin (Jae) Liao.

A ring made entirely of natural diamond (figure 1) was recently submitted to GIA’s New York laboratory. A large rough weighing approximately 196 ct was used to create this unusual 13.15 ct carved piece. It is common to find solid carved rings of jade and wood, which were traditionally worn as symbols of status or wedding rings signifying eternity. This is the first example of a solid diamond ring submitted to GIA for identification.

Figure 2. Needle clusters in the carved Fancy Dark gray diamond ring. Photomicrograph by Stephanie Persaud.
This solid type IaB diamond ring owes its Fancy Dark gray color to the graphite needles (figure 2) trapped during formation deep below the earth’s surface. Like famous gem-quality black diamonds such as the Black Orlov, the Korloff Noir, the Black Star of Africa, and the Spirit of de Grisogono, this diamond has clear spaces creating viewing windows that capture a snapshot of the ring’s formation history. The ring was fashioned from the Beaufort diamond from Canada’s Northwest territories and named the “Beaufort Ring.”

Figure 3. Fluorescence imaging using the DiamondView shows bundled dislocation networks. Image by Stephanie Persaud.
This diamond rough from which the ring was carved likely formed billions of years ago under high pressure. During regional metamorphism, H3 and NiN complexes were formed within the crystal lattice (K. Smit et al., “Black diamonds from Marange (Zimbabwe): A result of natural irradiation and graphite inclusions,” Summer 2018 G&G, pp. 132–148). These impurities were detected by photoluminescence spectroscopy. Infrared spectroscopy was used to detect the B aggregates and hydrogen complexes within the diamond lattice, categorizing this diamond as type IaB. Fluorescence imaging of the ring using the DiamondView showed bundled dislocation networks indicative of natural diamond growth (figure 3). While this diamond ring may not be a traditional piece, it carries many unique aspects capturing a snapshot of Earth’s history within a true infinity band. @chapter:35


Publication Year: 2023 Title: Trapiche Garnet from Vietnam Abstract: Figure 1. The color zoning in this 3.57 ct almandine garnet creates a cross structure that forms three-arm (top of A) and four-arm trapiche patterns (B) at every intersecting point of the crystal. These color zones are arranged along the edges of the dodecahedron (C). Photos by Le Ngoc Nang.
The garnet group contains the most gem-quality species for jewelry manufacturing. Phenomenal garnets such as almandine and pyrope species are also known for their four- and six-rayed asterism. Nevertheless, the trapiche structure found in emerald, ruby, sapphire, tourmaline, and quartz is extremely rare in garnet. This structure can be considered an immobile star phenomenon. Inclusions and color zoning are responsible for the formation of two-, four-, or six-arm trapiche patterns.
Recently, the authors received a garnet sample originating from Thac Ba Lake in the Yen Bai province of Vietnam, obtained by a local miner. The 3.57 ct polished gem was pinkish white and reddish brown, translucent to opaque, and measured 7.11 × 6.90 × 6.40 mm. The diamond-shaped pinkish white portions were surrounded by reddish brown color zones, creating three-arm and four-arm trapiche patterns (see the video below).
Gemological testing revealed the sample’s specific gravity of 4.16 and refractive index of 1.78. The stone displayed absorption spectra with distinct bands at 504, 520, and 573 nm, and it was inert under ultraviolet light for both long-wave and short-wave. All the data confirmed the almandine garnet species.

Figure 2. This 3.57 ct garnet emits vivid red through the trapiche patterns when shining a flashlight through the gem. Photo by Le Ngoc Nang.
Observing all sides of the stone, we identified 14 trapiche patterns, including 6 four-arm and 8 three-arm patterns, surrounding 12 diagonal faces (figure 1). The arms grew outward from the center of the four-arm trapiches and inward for the three-arm trapiches. While the reddish brown portions extended along the edges of the garnet crystal, the diagonal lines formed the faces of the rhombic dodecahedron crystal, a typical crystal habit of almandine originating from metamorphic rock. Interestingly, when illuminated with a flashlight, the trapiche patterns glowed a fascinating vivid red and outlined the diamond-shaped portions in sharp contrast (figure 2).
Using the gemological microscope, we found that the reddish brown color zones were not colored by inclusions. In contrast, we hypothesized that the reddish hue might be induced by the dispersion of metal ions—in this case, iron (E. Fritsch and G.R. Rossman, “An update on color in gems. Part 1: Introduction and colors caused by dispersed metal ions,” Fall 1987 G&G, pp. 126–139). The position of the color zoning along the edges of the crystal might be explained by the concentration of coloration elements in the crystal’s symmetrical planes. The reddish brown zones had higher transparency than the crystal planes, producing a “glowing net” when shining a light through the stone.
Although the trapiche pattern has been observed in several gems, it is rarely seen in garnet. The 14 trapiche patterns together in one specimen make this garnet unique.

	Trapiche Patterns in Vietnamese Garnet @chapter:10


Publication Year: 1987 Title: The Seven Types of Yellow Sapphire and Their Stability to Light Abstract: Colorless to yellow to intense orange sapphire will react quite differently to light or heat depending on the nature of the material and the origin of the color. The authors determined that there are actually seven types of "yellow" sapphire on the market today, which differ in the cause of color and the stability of the color to light: type 1—natural, light-stable color center; type 2—natural or irradiation-produced, fading color center; type 3—iron containing, not heated, light stable; type 4—iron containing, heated, light stable; type 5—surface-diffused additive, light stable; type 6—synthetic, light stable; and type 7—synthetic irradiated, fading. The authors examined more than 150 samples of yellow sapphire to confirm the seven types and document their different reactions to light, heat, and/or irradiation. One unexpected finding was that type 1 material can fade on heating even below 200°C, but that the color is restored by exposure to light. @chapter:12


Publication Year: - Title: Summer 2012 G&G Lab Notes Abstract: Large Artificially Irradiated Yellow Diamond
Multi-Treated Yellowish Green Diamond
Natural Green Diamond Artificially Irradiated for Color Enhancement
Pink Diamonds with 478 nm Peak
Rough Diamonds with a Green Coating
Jewelry Mounted with Red Feldspar from China
Hibonite Crystal
Unusual Green Color in a Jadeite Bangle
Greenish Blue Imitation Opal
Cultured Freshwater Pearl Necklace Resembling Natural Saltwater Pearls
Large Freshwater Cultured Blister Pearl
Luminescent Strontium-Calcium Aluminate Doped with Rare-Earth Elements
Near-Colorless HPHT-Grown Synthetic Diamonds from Advanced Optical Technology Co.

To view the full section, download the PDF above. @chapter:32


Publication Year: 2020 Title: Snowflake Inclusions in Mong Hsu Ruby Abstract: This partially healed fissure with a snowflake-like pattern is seen in a flux-heated Mong Hsu ruby. Photomicrograph by Nattida Ng-Pooresatien; field of view 1.3 mm.

The two main sources of Burmese ruby today are Mogok and Mong Hsu. Mogok is the traditional source of gem-quality ruby. The rubies from Mong Hsu are generally not as high in quality as those from Mogok, and typically show distinctive zoning with dark violet cores, a cloudy appearance, and multiple fractures. As a result, most stones from this deposit are heat treated at moderate temperatures using flux to repair fractures, improve clarity, and remove any unwanted blue color. Unheated Mong Hsu rubies are generally considered quite rare.
The author recently examined a 0.79 ct sugarloaf cabochon of pigeon’s blood ruby. Chemical analysis and gemological observation of internal features indicated that the origin of this stone was the Mong Hsu. Interestingly, microscopic examination with a combination of darkfield and oblique fiber-optic illumination revealed an open fissure with a snowflake-like pattern of flux residue (see above). The pattern is formed by the crystallization or devitrification of the glassy flux residue.
The snowflake is a symbol of the winter season and a traditional image associated with the Christmas holiday. This partially healed fissure resembling snowflakes is the first such feature the author has encountered in flux-heated ruby. @chapter:6


Publication Year: - Title: New and Notable Finds from the GIA Lab: Winter 2023 Abstract: These new finds from the GIA lab include unusual colors and patterns in natural and laboratory-grown diamonds.

This 2.20 ct Fancy Deep brownish orange treated HPHT-grown diamond owes its distinctive appearance to multiple defect concentrations created within the various growth sectors. Photo by Diego Sanchez.
HPHT Diamond with Unique Color Zoning
The GIA laboratory in Carlsbad recently encountered a 2.20 carat laboratory-grown diamond that received a color grade of Fancy Deep brownish orange. This diamond was grown via the high-pressure, high-temperature (HPHT) method and received subsequent HPHT treatment. These treatment processes created crystal lattice defects that resulted in the interesting coloration of the stone as well as a dramatic pink square positioned just under the table facet. Learn what color the pink square changes into when viewed through the pavilion.

This 0.63 ct tapered baguette-cut diamond showed two major color zones. Photo by Adriana Robinson.
Natural Bicolor Diamond
This unusual 0.63 carat diamond exhibits two distinct color zones, one that was graded Fancy Dark orangy brown and one that was graded Fancy Dark brown greenish yellow by GIA. Bicolor diamonds are incredibly rare and are typically caused by a combination of different crystal lattice defects. What makes this diamond even rarer is that its brown greenish yellow color zone displays chameleon properties, meaning it temporarily changes color upon heating or when left in darkness for an extended period of time. Discover what geologic conditions created this one-of-a-kind diamond.

This 1.03 ct natural Fancy Dark brown diamond has uneven color zoning and abundant black inclusions. Photo by Mei Yan Lai.
Brown Diamond Containing Carbon Dioxide
The Carlsbad laboratory recently examined a 1.03 carat natural Fancy Dark brown diamond with uneven color zoning and numerous black hexagonal inclusions. Upon analysis, the diamond was determined to contain submicroscopic solid inclusions of carbon dioxide. This brown diamond containing carbon dioxide is one of the few of its kind that GIA has encountered. Explore what was trapped inside these carbon dioxide inclusions. @chapter:35


Publication Year: 2007 Title: Summer 2007 G&G Lab Notes Abstract: Diamond with Bimineralic Inclusions
HPHT-Treated Type Ia Diamond with a Green Component Caused by the H2 Defect
Diamond with Intense “Rainbow Graining”
Natural Color Hydrogen-Rich Blue-Gray Diamond
Type IIa Diamond with Intense Green Color Introduced by Ni-Related Defects
Diamond with Zigzag Cleavage
HPHT-Grown Synthetic Diamond Crystal with Unusual Morphology and Negative Trigons
Idocrase in Jadeite: A Heavenly Home
Opal with Unusual Structure

To view the full section, download the PDF above. @chapter:11