Title: Aquamarine with Unusually Strong Dichroism Abstract: Figure 1. This 4.49 ct grayish blue aquamarine was unusual for its strikingly intense dichroism. Photo by Gagan Choudhary.

Recently, a transparent grayish blue oval mixed cut (figure 1) was submitted for identification at the Gem Testing Laboratory in Jaipur. The 4.49 ct stone (12.04 × 8.88 × 7.53 mm) was relatively clean to the unaided eye. Its RI of 1.582–1.590, birefringence of 0.008 with a uniaxial negative optic sign, and hydrostatic SG of 2.71 suggested a beryl, which we later confirmed with FTIR and Raman spectroscopy. The specimen’s natural origin was established by planes of dendritic platelets (usually ilmenite) oriented along the basal plane and liquid fingerprints.

The stone’s most striking feature was its unusually strong dichroism, displaying deep blue and pale bluish green colors (figure 2). The deep saturated blue resembled that of a top-quality sapphire. Such strong dichroism was reminiscent of Maxixe-type (irradiated) beryls, although their dichroic colors are usually deep blue and colorless. The deep saturated blue was seen along the e-ray, the pale bluish green along the o-ray. Such a pattern of color absorption is associated with aquamarine; the opposite effect occurs in Maxixe-type beryl, which appears colorless along the e-ray and deep blue along the o-ray (R. Webster, Gems, 5th ed., Butterworth-Heinemann, London, 1994, pp. 124–127).

Figure 2. The dichroic aquamarine displayed unusually intense dichroism, with a deep saturated blue along the e-ray (left) and a pale bluish green along the o-ray (right). The images were taken by fixing the polarizing filter on the camera lens and rotating the polarizer 90 degrees to separate out the two directions. Photos by Gagan Choudhary.
Further analysis was performed with UV-Vis-NIR spectroscopy to confirm the cause of color and differentiate between aquamarine and Maxixe-type beryl. Polarized spectra (figure 3) revealed an absorption peak at approximately 427 nm along the o- and e-rays, a typical feature in aquamarine due to the presence of ferric iron (see I. Adamo et al., “Aquamarine, Maxixe-type beryl, and hydrothermal synthetic blue beryl: Analysis and identification,” Fall 2008 G&G, pp. 214–226); an additional peak at about 370 nm also occurred along the o-ray. No features associated with radiation-induced color centers were present between 500 and 700 nm; these are typically observed in Maxixe-type beryls.

Figure 3. The aquamarine’s polarized UV-Vis-NIR spectra displayed Fe3+-related bands at approximately 370 and 427 nm.
Standard gemological properties along with absorption spectra and the pleochroic color directions were sufficient to identify this stone as aquamarine. It displayed the most intense dichroism we have seen in an aquamarine. While there are deep sea-blue aquamarines (see O. Segura and E. Fritsch, “The Santa Maria variety of aquamarine: Never heated,” InColor, No. 23, 2013, pp. 34–35) as well as deep blue Maxixe-type beryls, this was the deepest blue we have observed in an aquamarine with a grayish blue hue. Source: GIA @topic:3


Title: Decades-Old Synthetic Alexandrite Sheds Light on Modern Research Needs Abstract: Figure 1. These rough and faceted synthetic alexandrites, grown by Creative Crystals Inc., are shown in daylight (blue-green, top) and incandescent light (bottom). The crystals were grown on seeds parallel to the b pinacoid (1, 2), parallel to the r prism (3, 6) or parallel to the l dipyramid (4); the 13.49 ct faceted synthetic alexandrite measuring 16.6 × 11.8 mm (5) was grown on a seed parallel to the r prism. Photos courtesy of K. Schmetzer, The Journal of Gemmology.

For decades, much attention has been given to provenance studies of natural gemstones (such as emerald, ruby, and sapphire), as knowing their place of origin is significant in valuation. Synthetic colored stones do not command the same price per carat as their natural counterparts, but being able to pinpoint the growth technique and possibly the manufacturer is of value to the jewelry consumer, researcher, or collector. For example, many flux and hydrothermal producers can command a premium for their “luxury synthetics” over more quickly grown flame-fusion or Czochralski crystals.
The synthetic alexandrite produced by Creative Crystals Inc. from 1971 to the early 1980s exhibited true red-green color change (figure 1), and with no production for the last 30 years, these specimens are a rarity. A recent study by Karl Schmetzer, Heinz-Jurgen Bernhardt, and Thomas Hainschwang (“Flux-grown synthetic alexandrites from Creative Crystals Inc.,” The Journal of Gemmology, 2012, Vol. 33, No. 1–4, pp. 49–81) goes into fascinating detail on the company’s history, how the seed crystals were generated, and how the crystals were grown, unlocking the mystery of the distinct growth zoning observed in these particular synthetics.
The authors’ diligence in collecting a highly representative group of samples of this out-of-production material, as well as their thorough review of the available literature, is commendable. Woven into the article are interesting tidbits about the various seed origins and orientations used for growing these alexandrites, which demonstrates how both practical considerations and research-based findings can influence production and ultimately quality. A highlight of the article is the two-page history recounted by David Patterson, a former owner of Creative Crystals.

Figure 2. This microphotograph shows layered growth zoning associated with intense color zoning in a faceted synthetic alexandrite grown by Creative Crystals Inc.; immersion, field of view 5.3 × 4.0 mm. Photo courtesy of K. Schmetzer, The Journal of Gemmology.
To capture the uniqueness of these synthetics, the authors conducted meticulous microscopic studies. Several other techniques—including X-ray fluorescence, electron microprobe, and ultraviolet through infrared absorption spectroscopy—were used to describe corresponding chemical and optical zoning, pleochroism, absorption bands, and inclusions. The authors draw clear correlations between growth parameters and crystal characteristics, such as the impact of seed orientation on morphology. Even more significantly, they link the previously unexplained internal growth bands (figure 2) to multiple growth cycles – the growing crystals were actually removed from the furnace repeatedly to assess their progress. Similarly, I.G. Farben grew synthetic emeralds in the 1930s using multiple growth cycles (Karl Schmetzer and Lore Kiefert, “The colour of Igmerald: I.G. Farbenindustrie flux-grown synthetic emerald,” The Journal of Gemmology, 1998, Vol. 26, No. 3, pp. 145–155). However, Creative Crystals would cool the melt slightly during cycles lasting one week whereas I.G. Farben would keep the melt at a constant temperature during 20-day cycles. Temperature gradients were not used to grow synthetic alexandrite for several more years, according to Dr. Schmetzer. A comparison with commercially produced flux alexandrite from Russia also illustrates how characterization techniques can reveal details of the growth process.
The article is not a light read, 33 pages in length with 46 figures and well over 100 images. But for crystal growers or those simply interested in understanding more about gem synthesis, this article serves as a window into the crystal growth engineering process and reveals how a specimen’s characteristics can shed light on its origin. Other synthetic materials have been similarly studied, and the need for such analyses continues to increase as additional synthetics and more advanced characterization techniques emerge. Source: GIA @topic:3


Title: Kathryn Kimmel Abstract: In Kathryn Kimmel’s nearly 30 years as head of GIA’s marketing and public relations efforts, she radically improved the Institute’s visibility in the trade and the public eye. Kimmel established the annual GIA Jewelry Career Fairs and the consumer outreach program on the Institute’s gem identification and grading reports and the 4Cs. She was the first woman on GIA’s executive team, beginning as director of marketing in 1990 and retiring as senior vice president and chief marketing officer in 2019.
A third-generation jeweler, Kimmel learned repair and sales at her parents’ Los Angeles store. She visited GIA as a child—while her father was taking the Institute’s courses—and met Richard T. Liddicoat and Robert Shipley Jr. She even spent her birthdays at the California Jewelers Association’s annual shows. Yet she resisted going into the family business and took a detour to major in theater arts in college and work in entertainment production.
By 1990, when Kimmel met GIA’s then-president Bill Boyajian, she had returned to the industry, managed the family store, and risen to vice president of marketing for manufacturer Nova Stylings. At Nova she learned marketing principles from renowned expert Guy Kawasaki. Boyajian was looking for a new director of marketing and was impressed by her background and drive. She joined GIA that summer.
Kimmel established a public relations department, streamlined and modernized GIA’s brand identity and marketing materials, and revamped the advertising strategy. She directed the launch of the Institute’s first website and with Boyajian wrote the Institute’s first mission statement. When she found herself advising students about how to transition into the trade, she recognized the need for a career fair. With the support of the Jewelers 24 Karat Club of Southern California, GIA’s first career fair was held in Santa Monica in 1991. As the industry’s largest recruiting event, it has expanded to five GIA locations and been an avenue for countless GIA graduates to begin their careers.
“My heart will forever be with the students—seeing them study at GIA, coming to GIA’s Jewelry Career Fair and becoming industry leaders has been one of the most rewarding parts of my job,” Kimmel said.
In the years since, Kimmel increased the Institute’s participation in international trade shows and industry events, co-chaired its International Gemological Symposiums, and steered GIA’s marketing activities in an ever-evolving industry. Echoing her first visit to GIA decades prior, she grew to see Liddicoat as a mentor and father figure and refers to Shipley as one of her heroes.
In 2006 GIA honored Kimmel with the Richard T. Liddicoat Award for Distinguished Achievement, its highest tribute. Other recognition includes the American Gem Society’s Triple Zero and Distinguished Service awards, the Jewelers 24 Karat Club Excellence in Service Award, the YWCA’s Tribute to Women in the Industry (TWIN) award, and the Women’s Jewelry Association Award for Excellence in Promotion. In 2016 she was named one of Luxury Daily magazine’s 25 “Luxury Women to Watch.” Kimmel is a founding member and past president of the WJA’s Los Angeles chapter, and has served on the boards of WJA, the Jewelers 24 Karat Club of Southern California and the Jewelry Information Center. Source: GIA @topic:9


Title: Pink Euclase Abstract: Figure 1. The 4.08 ct orangy pink euclase. Parallel pink color zoning is observed under the table. Photo by Shunsuke Nagai.

GIA’s Tokyo laboratory had the opportunity to examine an orangy pink faceted stone, weighing 4.08 ct and measuring 13.00 × 9.90 × 5.23 mm, with a hydrostatic specific gravity of 3.09 (figure 1). It had optically biaxial features based on trichroic colors of yellowish orange, pale orange, and orangy pink, and refractive index values of 1.652–1.671 with a birefringence around 0.019. The stone was inert to ultraviolet light sources.

Figure 2. Transparent platy crystal inclusions and aligned particles were observed. Photomicrograph by Mari Sasaki; field of view 1.85 mm.
Transparent platy crystals and straight graining were observed under the microscope (figure 2). There were no signs of treatment such as coating or clarity enhancement. Gemological properties matched euclase, which was confirmed by comparing the Raman spectrum with the RRUFF database (reference spectrum R050032).
Euclase is one of several collector’s minerals discovered in the eighteenth century in Brazil (D. Atencio, “The discovery of new mineral species and type minerals from Brazil,” Brazilian Journal of Geology, Vol. 45, No. 1, 2015, pp. 143–158) and classified as a beryllium aluminum hydroxide silicate, with an ideal chemical formula of BeAlSiO4(OH). Crystals are found worldwide and occur in a range of colors such as colorless or white, blue, green, and yellow (e.g., S.M. Stocklmayer, “A new occurrence of euclase in Western Australia,” Australian Journal of Mineralogy, Vol. 18, No. 2, 2017, pp. 39–44). Gem-quality pink euclase was first reported in 2018 (M.B. Leybov, “Denver 2018: ‘Minerals of Mexico,’” Mineralogical Almanac, Vol. 24, No. 1, pp. 58–63), and this color is considered rare.

Figure 3. UV-Vis spectrum of this orangy pink euclase. The 470 and 540 nm absorption peaks probably originated from Mn3+ and the 381 nm peak from Fe3+.
The causes of color for euclase have been discussed in many studies (e.g., E. Gübelin, “Sapphire-blue euclase, a new collector’s gem,” Winter 1978-1979 G&G, pp. 104–110; M. Mattson and G.R. Rossman, “Identifying characteristics of charge transfer transitions in minerals,” Physics and Chemistry of Minerals, Vol. 14, No. 1, 1987, pp. 94–99; S. Stocklmayer, “Blue euclase from Zimbabwe – a review,” Journal of Gemmology, Vol. 26, No. 4, 1998, pp. 209–218). According to these three previous studies, blue to green color in euclase is believed to be caused by an Fe2+-Fe3+ charge transfer and Fe2+-Ti4+ transitions or the presence of trivalent iron. Moses et al. (Summer 1993 Gem Trade Lab Notes, pp. 125–126) reported a greenish blue euclase colored by chromium. Gilles-Guéry et al. (“Mn3+ and the pink color of gem-quality euclase from northeast Brazil,” American Mineralogist, 2021, in press) determined that pink coloration due to the absorption between green to blue with two broad peaks at 470 and 540 nm is caused by Mn3+, while the orange hue is related to the rising slope in the UV domain combined with an additional absorption peak at 381 nm originating from Fe3+. This stone showed a UV-Vis absorption spectrum (figure 3) similar to the pattern due to Mn3+ reported by Gilles-Guéry et al. (2021), and trace Mn concentrations around 60 ppm were detected by LA-ICP-MS. These characteristics suggest that the orangy pink color seen in this stone is possibly caused by manganese. This is the first such example examined at GIA. Source: GIA @topic:2


Title: Not All That Glitters is Gold — Sometimes it is Mozambican Rubies Abstract: Wim Vertriest, supervisor of GIA field gemology, presented his lecture "A Decade of Mozambican Rubies" on Jan. 30, 2020 as part of the GIA Guest Lecture Series. Video Duration: 1:21:10
There was something striking about the talk, “A Decade of Mozambican Rubies,” that Wim Vertriest, head of GIA field gemology, gave at GIA in Carlsbad recently. It’s only in the past 15 years that there has been intense consumer scrutiny of gemstone origins. Previously, unless a stone was from a legendary locale, such as Kashmir for sapphires, origin was largely ignored.
Vertriest’s talk, however, dove deep into rubies from a new and lesser known locale — Mozambique — focusing on their mining history, characteristics and market demand. Throw in some tips on field gemology from GIA’s “viking” gemologist, Vertriest, and the talk was good as gold.

These rubies (1.07-4.62 ct) are from Northern Mozambique. Photo by Robert Weldon/ GIA. Courtesy of Tommy Wu, Shire Trading Ltd., Hong Kong.
Mozambican Ruby Discovery
Mozambican rubies, unheard of a decade ago, have become the most common ruby in the international marketplace since their discovery in 2008. Mozambican rubies now make up a significant part of the rubies sold at major trade shows.

A group of garimpeiros, or mineral prospectors, mining in the bush surrounding Montepuez. Photo by Vincent Pardieu/GIA.
Timeline from Discovery to Present
2008 ‒ The first confirmed ruby is found at the Niassa Reserve, an area set apart for wildlife such as lions and elephants. Its protected status doesn’t stop artisanal miners from flocking to the site, however. Mining virtually ends in summer 2009 when water sources dry up and miners are forced to leave.
2009 ‒ Rubies are discovered next to a highway near the town of Montepuez. Tens of thousands of artisanal miners flock to the site. Within a year, international traders start acquiring rubies in the towns near the mines. Stones are brought to cutting and trading centers like Bangkok, making Montepuez the dominant source of rubies for the Thai ruby trade.
2014 ‒ Mwiriti Limitada, which owns a significant number of mining licenses around Montepuez, partners with the natural resource company Gemfields to form MRM. The first rubies are exported following government-approved processes.
2020 ‒ In less than a decade, ruby mining has transformed from 100 percent artisanal to largely formalized. But even though several companies have set up large-scale ruby mining operations in Mozambique, there still remains many artisanal miners.

Maninge Nice-type rubies (here, up to 17 mm) are typically a deep red with strong fluorescence but also flat and highly-included. Photo by Vincent Pardieu/GIA.
Mozambican Ruby Quality
Mozambique produces two main types of rubies: Maninge Nice (known as Bor Daeng in Thai) and Mugloto (Bor Som in Thai). The names of these terms come from the names of the most productive mines in the Montepuez area.
Maninge Nice rubies have brilliant color, intense saturation and strong fluorescence. But they also tend to be flat in shape and heavily-fractured, yielding smaller rubies when cut. Fractured stones are treated through flux healing to improve their appearance and durability. This process entails heating the stones in the presence of borax, which allows fractures to heal.
Mugloto rubies are bulkier in shape and have fewer fractures than Maninge Nice rubies. They tend to have darker tones and weaker fluorescence, however. Mugloto stones sometimes require heat treatment to remove blue overtones and give the stones livelier color. Detecting this low temperature treatment is challenging and often requires advanced instruments.

Amphiboles are common mineral inclusions in Mozambican rubies, Vertriest explained during his presentation. Photomicrograph field of view 1.32 mm. Photo by Jonathan Muyal/GIA.
GIA in Mozambique
Vertriest’s expertise in rubies comes from years on the field with GIA, collecting research samples in Africa, Asia and Europe. Purchasing gems near its production site is the most foolproof way of ensuring that the stones GIA studies are actually from that locale. According to Vertriest, “if you don’t go, you don’t know.”
The most reliable samples are Type A, which are samples mined directly by the gemologist.“I go to the mine, hit a rock, 10-carat ruby comes out,” Vertriest said.
The other types of classification beyond that are qualified by how the gemologist collects them:

Type B ‒ the gemologist witnesses the samples being mined
Type C ‒ samples are purchased from a miner at the mining site
Type D ‒ samples are purchased from a miner but not onsite
Type E ‒ samples are purchased from a secondary source (not the miner) close to the mine
Type F ‒ samples are purchased from a secondary source on the international market

Most of the samples that GIA collects are Type D or E, supported by types A, B and C when available. The research done on these gemstones goes towards supporting GIA’s colored stone identification and origin reports.

Aaron Palke, senior research scientist at GIA (left), and Vertriest sort through gem gravel in Mogok, Myanmar, in December 2018. Photo by Kevin Schumacher/GIA.
How to Become a Field Gemologist
Vertriest has a master's degree in geology with a focus in geodynamics and geofluids, a Graduate Gemologist degree from GIA and a diploma in gemmology from the Gemmological Association of Great Britain.
When asked by a student which degree is the most useful, however, Vertriest answered “common sense.”
“Field gemology isn’t a trade you just jump into,” he said. “It’s a trade that gemologists grow into through extensive travelling, asking the right questions and working on a research team or as a gem grader. An advanced degree in geology, chemistry or physics is also a must, since field gemologists are part of GIA’s research department.”
Vertriest’s tools of the trade include a loupe (indispensable, he said) and a gem torch, although he admits a flashlight or even a phone light might work just as well. Having a reliable source of light helps him determine the quality of a stone.
“Traders often sell rubies under pink umbrellas and sapphires under blue roofing; these conditions really enhance the appearance of stones and can make them look better than they actually are,” he said. “Having a torch (or a flashlight) also helps when examining gems in dim locations or when it’s dark out.”
When asked why he works at GIA, Vertriest answered that working for GIA opens many doors. It allows him to go to large scale mines and artisanal mining sites as well as gem trading offices to study rubies and other gemstones.
“When I go, it’s not, ‘Hi, Wim here.’ It’s ‘Hi, GIA here.’ Once I lose that badge, half the doors close,” he said.
GIA is an incredible resource, he said. GIA’s lab and research departments host some of the field’s greatest researchers who are engaged in some of the most pressing gem issues of the time. In other sectors, field researchers have to rely on external analytical services and wait months for data. Because GIA has its own analytical department, however, Vertriest can request a complicated analysis in the morning and get results after lunch.
The gem trade is exciting when working with GIA, Vertriest said, but prospecting on your own can be “an incredible gamble.” Source: GIA @topic:1


Title: Unique Colombian Emerald and Matrix Suite Abstract: Figure 1. Emerald and matrix suite, 112.25 carats total. Photo by Jessa Rizzo.
The author recently examined a unique suite of cabochon stones consisting of emeralds with brown matrix weighing 112.25 carats total (figure 1). This spectacular set is reportedly from the Muzo mine in Colombia. Similar material with matrix has been found in Chivor, but never of comparable quality. The miners decided to cut a matching set of cabochons that could be made into a necklace and a pair of earrings. In 2021, Misael Angel Rodriguez of Colombia brought this unique set to the Tucson gem shows, where it received considerable attention. It was later purchased by Desmond Chan and Davey Thomas of Gem Arts International and submitted to the AGTA Spectrum Awards, receiving honorable mention in 2022. To this day, the author has yet to encounter such a remarkable set of matching emerald with matrix cabochons.

Figure 2. Cluster of pyrite crystals in emerald and matrix. Photomicrograph by Jessa Rizzo; field of view 1.99 mm.
Under the microscope, the matrix has a coarse, sand-like texture. Raman spectroscopy identified the matrix as primarily consisting of an aggregate of feldspar grains displaying a banded pattern. Under magnification, the green gem area showed jagged multiphase inclusions along with euhedral pyrite crystal inclusions (figure 2). Laser ablation–inductively coupled plasma–mass spectrometry and inclusion observation were consistent with a Colombian origin. It is remarkable to see such a well-matched suite of unusual emeralds with matrix in the gem trade. Source: GIA @topic:1


Title: Mandela Day Libraries Encourage a Love of Reading, Education Abstract: “Education is the most powerful weapon which you can use to change the world,” Nelson Mandela once said. Students at Refentse Primary School in Limpopo, South Africa recently expanded their education by participating in GIA’s Junior Gemologist program. Photo by GIA

ship•ping con•tain•er
noun \ˈSHipiNG kən-ˈtā-nər\
: a large metal, corrugated box used to transport goods by ship, airplane, train or truck

li•brary
noun \ˈlī- brer-ē\
: a place with a selection of books, magazines and other reading or resource materials available to borrow

The objects of these definitions may seem unrelated, but for several non-profit organizations in South Africa, shipping containers are a great solution to house school libraries where there were none before.

GIA recently collaborated with the Mandela Day Libraries project to sponsor two container libraries for nearly 1,100 students at the Moime and Refentse primary schools in rural Limpopo, South Africa.

The Mandela Day Libraries project is dedicated to bridging the gap in literacy and reading proficiency in schools throughout South Africa by recycling and retrofitting shipping containers with new flooring, insulation, electricity and bookshelves to create libraries. Breadline Africa, a nongovernmental organization and internationally registered South African-based charity, is the main partner of the program.

The new libraries are funded by the GIA endowment, which supports education and scholarship programs, and hold nearly 2,500 educational books, many of which were donated by GIA staff.

“We’re thrilled to bring these libraries to the students of the Moime and Refentse primary schools and hope they further ignite their interest in education,” said Bev Hori, GIA’s chief learning officer and vice president of education.

	Bev Hori (left), GIA's chief learning officer and vice president of education, and Alta Brown Steenkamp, Vodacom Change the World Volunteer at The Nelson Mandela Foundation, work to promote literacy through the Mandela Day Libraries project. Photo by GIA
The two GIA-sponsored libraries were unveiled Feb. 19 and 20 with opening ceremonies that included local government representatives, teachers and tribal authorities. GIA also hosted 20 pupils in its Junior Gemologist program during the events. The program offers students the opportunity to discover the world of gemology through hands-on, practical training.

Moime and Refentse primary schools mark the installment of the 36th and 37th Mandela Day library since the program’s inception in 2011. The project also trains librarians to manage the facilities and inspire a love of reading among the students.

“The students have the motivation and potential to improve the state of the world they experience,” Hori said. “Education is the key to helping them realize their visions of a better life for themselves and their communities.”

View Gallery Source: GIA @topic:6


Title: Interesting Set of Blue “Rough” Gemstones Abstract: Figure 1. This set consists of a 48.63 ct piece of manmade glass (left), 9.17 and 6.21 ct laboratory-grown sapphires with resin imitation of matrix on the surface (center), and an 8.46 ct natural blue sapphire rough (right). Photo by Annie Haynes.
The selling of simulants and synthetics mixed with parcels of natural stones is an old form of deception. It usually happens close to mines, where inexperienced buyers assume the gemstones come directly from the source—and where advanced testing is likely not available prior to the purchase.
The Carlsbad laboratory recently received a group of four blue rough stones (figure 1) submitted as natural sapphire for identification and origin reports. The largest weighed 48.63 ct and measured approximately 22.88 × 19.67 × 15.19 mm. The material was partially fashioned, with evidence of polish lines on the surfaces. Careful microscopic examination revealed multiple gas bubbles, distinct flow marks associated with blue coloration, and conchoidal fractures. Weak snake pattern bands were observed under the polariscope. The hydrostatic specific gravity was 2.48. These observations suggested a glass imitation, which was confirmed by comparing the infrared spectrum with that of manmade glass.

Figure 2. A resin imitation of matrix on the surface of a laboratory-grown sapphire. Photomicrograph by Najmeh Anjomani; field of view 7.19 mm.
The next two were more convincing imitations of natural sapphire. They weighed 9.17 and 6.21 ct and measured approximately 16.00 ×10.06 × 8.30 mm and 10.31 × 9.38 × 8.71 mm, respectively. Resin that coated the surface (figure 2) resembled matrix composed of natural minerals commonly seen on natural corundum rough. The resin started to melt with the touch of a hot pointer. Brownish materials trapped in cavities resembled iron oxide stains one would expect to see in natural rough. Though difficult to see inside of the stones due to their rough surfaces, a few gas bubbles were observed through a small transparent area. Raman spectroscopy matched corundum, and immersion in water (figure 3) revealed curved blue banding. Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) detected no gallium and revealed trace elements of impurities consistent with synthetic corundum. Hydrostatic specific gravity values were 3.76 and 3.59, respectively. Both values were below the SG of corundum (3.9–4.05), a result of the lower SG of the resin on the surface. Both were reported as laboratory-grown sapphire with a comment stating, “Imitation matrix and resin is present on the surface.”

Figure 3. Curved blue banding visible in the 6.21 ct laboratory-grown sapphire immersed in water. Photo by Najmeh Anjomani.
The last piece of rough was a blue stone weighing 8.46 ct and measuring 13.85 × 9.89 × 7.60 mm. The frosted natural surface made it difficult to see inside the stone, but some natural-looking fingerprints and strong, straight inky blue banding were observed. The Raman spectrum matched with corundum, and a hydrostatic SG of 3.96 confirmed it. The stone was immersed in methylene iodide to confirm the zoning was straight and not curved. Medium chalky blue fluorescence to short-wave UV and a strong 3309 cm–1 series in its Fourier-transform infrared (FTIR) spectrum proved that heat treatment had been applied to the stone. LA-ICP-MS revealed natural chemistry, including about 200 ppma iron and other trace elements such as gallium (~25 ppma), vanadium (~3.5 ppma), magnesium (~35 ppma), chromium (~1.5 ppma), and titanium (~80 ppma). Based on appearance, color zoning, and chemistry, this stone was reported as natural sapphire, heat treated, with Madagascar as the country of origin.
This was an interesting study of how synthetics and simulants can be mixed with their natural counterparts to misrepresent a parcel. However, careful examination and standard gemological testing are usually enough to identify them correctly. Source: GIA @topic:3


Title: An Interesting Rose Quartz from Madagascar Abstract: Figure 36. This 3.83 ct rose quartz from southern Madagascar contains an inclusion suite that has not previously been documented in such material from any locality. GIA Collection no. 37702; photo by Robert Weldon.

              In October 2007, Fabrice Danet (Style Gems, Antsirabe, Madagascar) informed us about a new find of rose quartz from Madagascar that contained some unusual inclusions. He first saw the material in April 2007, when a local dealer offered him a few kilograms of rather small pieces said to be morganite. About half the rough contained noticeable green inclusions, and Mr. Danet subsequently purchased 2 kg. In June 2008, he obtained 10 kg from a 100 kg parcel consisting mostly of small pieces. This time it was offered as rose quartz by a man who actually mined the material. He reported that it came from several small pits in a weathered pegmatite that contained beryl, black tourmaline, mica, clay, and areas of rose quartz. According to the miner and several local dealers, the deposit is located in the Ihosy area of southern Madagascar.

So far, Mr. Danet has cut about 200 stones, the largest of which weighs 27 ct. On examining the material with a loupe, he noticed that the green inclusions had a shape and color that were typical of diopside. Also present were orange hessonite-like inclusions and some very thin needles.

Mr. Danet donated to GIA a light pink 3.83 ct oval brilliant cut (figure 36) and three pieces of rough that contained obvious dark green and bright orange transparent-to-translucent inclusions. The faceted gem was confirmed as rose quartz by standard gemological testing. It contained a relatively large green inclusion adjacent to an orange inclusion (figure 37) that were both visible through the table facet and made excellent targets for Raman microanalysis. As suggested by Mr. Danet, the green inclusions were indeed diopside and the orange crystals were grossular. While we have encountered garnets before as inclusions in rose quartz (from Sri Lanka), this is the first time this combination of inclusions has been observed in rose quartz from any locality. As an added bonus, the very small blade-like to acicular inclusions in the stone were identified as epidote.

	Figure 37. The green inclusions in this rose quartz from Madagascar proved to be diopside, and the orange crystalline masses were identified as grossular. Also present are some needles of epidote. Photomicrograph by J. I. Koivula; field of view 2.7 mm. Source: GIA @topic:2


Title: Polymer-Coated Serpentine Abstract: Figure 1. The serpentine pendant before and after cutting. Photos by Lai Tai-An Gem Lab.

Jadeite, nephrite, serpentine, chalcedony, and quartzite were all referred to as “jade” in ancient China, where objects were defined by their craftsmanship rather than the materials themselves. The term is still widely used in the Chinese market for many types of materials. “Xiuyan jade” is actually a form of serpentine, so named for Xiuyan, a city in China’s Liaoning province where serpentine deposits are abundant.

The pendant in figure 1 was submitted to the Lai Tai-An Gem Laboratory by a client who claimed the material was jadeite jade. The pendant, which weighed 222.03 ct and measured 58 × 37 × 17 mm, showed a light green carved fish on a brown and yellow background. At first glance, it appeared to display a plastic-like luster.

Identical spot RIs of 1.56 were obtained from two different parts of the object, and an SG of 2.40 was determined. Both measurements were lower than expected for jadeite. The SG may have been affected by a polymer coating; this was partially confirmed when bubbles were observed on some surface areas under magnification. Microscopic observation proved that the piece was solid and not assembled. It was inert under long-wave and short-wave UV light from an ultraviolet viewing cabinet, whereas most polymer-coated objects show weak to strong reactions. The client granted permission to cut the piece in two for further analysis.

DiamondView observations of the cross section revealed an inert reaction from the object’s interior, but the coatings on the surface produced a strong bluish fluorescence (figure 2). FTIR spectroscopy on the interior identified the material as serpentine, but peaks at 3060, 3025, 2932, and 2858 cm–1, obtained from the surface, showed that a polymer was present. Peaks at 1045, 673, 564, and 485 cm–1, detected from both the interior and the surface, were indicative of serpentine (figure 3); this was confirmed by Raman spectroscopy.

Figure 2. DiamondView imaging showed that the inner portion of the serpentine was inert, while the surface exhibited a strong bluish fluorescence. These images show the reflection from the polymer-coated surface in visible (left) and UV light (right). Images by Lai Tai-An Gem Lab.

Figure 3. FTIR spectroscopy revealed peaks indicative of coating at 2858, 2932, 3025,
and 3060 cm–1 (red) and serpentine peaks at 485, 564, 673, and 1045 cm–1 (blue).
Coatings are normally applied to gem materials to improve luster and, in some cases, provide a degree of stability. This was the first case of coated serpentine we have encountered. Care should be taken to identify such coatings; the simplest way to detect the treatment is to check for any unusual reaction under the ultraviolet viewing cabinet, but in this case, the UV reaction only showed in the ultra-short-wave UV of the DiamondView. Serpentine’s characteristically low hardness makes it a very suitable carving material, but any treatments applied to it should be fully disclosed. Source: GIA @topic:12


Title: GIA Field Gemology Team Explores Sapphire Mines at Ilakaka, Madagascar Abstract: Exploring Madagascar’s Sapphire Mines

	Tour Ilakaka’s sapphire mining areas with GIA field gemologists.

	In this short video you will accompany GIA Field Gemologist Vincent Pardieu and his team as they introduce you to Madagascar’s Ilakaka sapphire mining area. Located in the south of the island of Madagascar, the Ilakaka area is one of the world’s largest sapphire deposits, and currently one of the most active. Potential sapphire deposits cover an area of about 75x62 miles (120x100 km).

	“Madagascar has huge potential as a sapphire producing country,” says Pardieu. “GIA will keep visiting the island to study and document all its deposits.” According to Pardieu, the institute has already compiled the most accurate map of the island’s sapphire workings yet published.

	Discovered at the end of 1998, the area around Ilakaka produces many other gems besides corundum, including chrysoberyl, spinel, garnet, tourmaline, and zircon.

	Miners seek sapphire-rich layers concentrated in former river beds that geologists call paleochannels. Using hand tools, they dig simple pits to reach the gems, which they wash in nearby rivers. The pits are often less than a meter in diameter to minimize the risks of collapse. Some pits go as deep as 197 feet (60 meters). “Finding gem-rich gravel is the only thing that matters for the miners,” says Pardieu.

	In this video, you’ll follow him down one such pit—about 118 feet (36 meters) deep—so he can see the conditions under which the miners work with his own eyes. “It is hard work to say the least,” reflects Pardieu.

	You’ll see unparalleled aerial footage of the mining area as GIA’s drone skims over the miners’ heads. You’ll also be treated to a unique aerial view of Ilakaka itself.

	A big goal of the trip is the gathering of samples for GIA’s reference collection, and that requires gaining the confidence of local miners. “Once people know what you’re here for, the stones start to appear,” explains Pardieu. It’s also good if you can stay in the area for a while, he says. “Time is our best ally in all these kinds of expeditions,” continues Pardieu. “The longer you stay, the more chance you have of seeing something interesting.”

	This video was compiled from two separate Madagascar expeditions—FE39 and FE55—that took place in 2012 and 2014 respectively. Besides Vincent Pardieu and cameraman Didier Gruel, expedition participants included Boris Chauviré, Jonathan Muyal, and Stanislas Detroyat. Source: GIA @topic:1


Title: The Stories Behind the Photos: A Gigantic Aquamarine and ‘Gaudy’ Nature Abstract: The tools of a traveling field photographer include a map, notebook, pen, mobile phone with compass app and a digital camera. Photo by Robert Weldon

Robert Weldon has traveled the world in pursuit of the most fascinating and beautiful gemstones as a gemological photojournalist. He has climbed into mines, trekked miles to the next location and waited patiently for the perfect light. He is as enthralled with the people who mine and deal with gemstones as he is with the places and cultures where they are found.

Weldon has traveled to some of the world’s major gem sites, including Burma, India, East and South Africa, Colombia, Bolivia, Brazil, Russia, and several other gem sources. His photographs are published in scores of international gemological, jewelry and consumer publications, illustrating his own and other authors’ articles, and in several books. They have also appeared regularly on the cover Gems & Gemology since 2008.
Every one of Weldon’s photos has a story to tell  — whether it is how he conceived the image, how he chose to show the gem at its best, or how he decided to show the context of the locality where the gem was found. Over the course of three decades, he has photographed some of the world’s most important gems and jewelry.
He combines art and gemology in a way that makes us even more appreciative of what we see.
“The industry that we are all a part of and love so much is very much a visual one. Everything really relies on our senses, but particularly our eyes and what we see and feel,” he says. “On the basis of a good image we often make decisions in an instant that transfer millions of dollars across the world.”
Here are some of his favorite gem stories.
Don’t Make a Habit of This

The historic Munsteiner aquamarine carving Dom Pedro was donated to the Smithsonian Institution by Jane Mitchell and Jeffery Bland and is housed in the National Museum of Natural History's Janet Annenberg Hooker Hall of Geology. Photo by Robert Weldon
Weldon was given the opportunity to photograph the 10,363 carat (ct) Dom Pedro Aquamarine, a 14-inch tall obelisk carved by master gem sculptor Berndt Munsteiner, at a Tucson show more than 20 years ago.
Unable to fit it into his small portable studio, he and gem dealer Evan Caplan decided to take it out to the desert. They placed it carefully on a rock with the iconic Mission San Xavier del Bac serving as the backdrop. The ancient mission, constructed between 1783 and 1797, juxtaposed against this modern, angular gem sculpture, created a dramatic image.
“Evan crouched inches away, ready to dive for it — and save it — as it swayed slightly in the breeze,” Weldon recalls. They got the shot and spirited the sculpture to safety in Caplan’s booth.
Months later, Munsteiner marched towards Robert, who was “transfixed, mortified and scared” as the legendary carver approached him.
Then he beamed. “Robert, that was a great picture,” he said. After a pause, he added: “By the way Robert, do you know what the value of this stone is?”
Luckily, the photo was a success and was featured in JCK magazine; Munsteiner says a copy hangs in his living room.
“This is something you should never do! It is much too dangerous and too much of a risk,” Weldon says. “Never, never would I do that again.”
The Dom Pedro is “the largest single piece of cut-gem aquamarine” according to the Smithsonian Institute, where it has been on display since 2012. It so breathtaking that the Smithsonian said it is “one of the few objects in the world that can hold its own in a display case just 30 feet from the Hope Diamond.”
A Stunning Stalactite

“Atlantis” Star of the Congo Mine Lubumbashie, Haute-Katanga Democratic Republic of the Congo Approximately 31.75 kg and measures 70 cm in length, by 25 cm in width.   This magnificent specimen of malachite and chrysocolla is from an area in the southern part of the Democratic Republic of the Congo known as the “copper crescent,”  an area famous for its copper mines.    Broken chrysocolla-coated stalactites reveal malachite cores. Look closely; often there is a small hole in the center. These are tubes through which solutions dripped and caused the downward growth of the stalactite. Where these straw-like openings don’t exist, solutions ran down the outside of the stalactite, making them thicker.   Some of the stalactites are oddly curved and bulbous. When stalactites develop they are under the influence of gravity and should form straight growth. The curvature suggests an outside influence like air or water currents caused more growth on one side. All in all, this amazing specimen is reminiscent of a dreamy underwater scene or fantasy world leading to its name, Atlantis. Photo: Robert Weldon
This malachite and chrysocolla specimen, found in a cave in the Congo, weighs 80-90 pounds and is a meter and a half in length.
“Interestingly, it is on display upside down. But we didn’t want to photograph it [or display it] the way it formed in nature, because such positioning would break those beautiful stalactites,” Weldon says.
The GIA Museum acquired this “stunning” malachite and chrysocolla specimen at the 2020 Tucson shows. It has been nicknamed “Atlantis” for its resemblance to the exotic underwater realm. See a video presentation and explanation of its formation.
If you look closely, you may see a small hole in the center of each stalactite. Solutions dripped though these straw-like tubes and caused the downward growth of the stalactite. If a tube opening was not there, the solutions ran down the outside of the stalactite, making them thicker.
Stalactites normally develop under the influence of gravity and should form straight growth. Some of the stalactites in this specimen are oddly curved and bulbous, which suggests an outside influence such as air or water currents that caused more growth on one side.
“You really begin to understand the formation of gemstones just by looking at this. You can see how drip by drip mineral-rich waters gave rise to those colorful stalactites and this is what you see today,” Weldon says. “It is a spectacular display of how only nature can be as gaudy as this. Wow, what a piece — it’s just absolutely stunning.”
Watch a GIA Knowledge Session where Director of the RTL Gemological Library Robert Weldon, Senior Manager of Research Dr. Aaron Palke, and Supervisor of Field Gemology Wim Vertriest offer an exclusive look at GIA field gemology expeditions through previously unpublished photographs. Source: GIA @topic:7


Title: Unusual Curved Color Zoning In Emerald Abstract: While curved color zoning is typically associated with melt-grown synthetics, particularly flame-fusion products such as synthetic corundum and synthetic spinel, an unusual natural emerald with this feature was recently examined in the Carlsbad and Bangkok laboratories. This 1.17 ct emerald was obtained for GIA’s permanent reference collection (sample number 100305160993) at a street market in Kabul, Afghanistan, for its very unusual inclusion scene. The stone was represented as being of Afghan (Panjsher) origin, but the internal inclusions seemed to resemble those of emeralds collected from the Swat Valley of Pakistan. Careful chemical analysis by laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) was performed at the GIA lab in Bangkok. The chemical data showed a fairly even composition within the sample except for chromium, which varied proportionately with the green color zoning (from approximately 300 to 9000 ppmw Cr). The chemical data of the unusual emerald were compared to those of reference standards from known deposits, particularly Panjsher and the Swat Valley, to investigate its probable origin. The data showed a close match only with the reference emeralds from the Swat Valley, making that the most likely origin.

Figure 1. This 1.17 ct emerald, which hosted pyrite and carbonate crystals, displayed unusual curved zoning. Photo by Sasithorn Engniwat.
The gemological properties showed an RI of 1.589–1.597 and a visible spectrum consistent with emerald. The stone showed no reaction to a standard 4-watt gemological UV light source. Microscopic examination revealed numerous inclusions of pyrite, carbonates, and reflective thin films oriented perpendicular to the optic axis (parallel to the length of the stone), a typical assemblage of a natural emerald. The most unusual observation about this stone was a prominent green “S” shape color zone that ran down its length (figure 1). Emerald’s hexagonal structure would ordinarily lead one to expect planar or angular color zoning related to the crystal morphology. The presence of curving zones in a faceted emerald was an anomaly that needed further examination.

Figure 2. Arrays of tabular offset pyrite fragments were seen throughout this unusual emerald. Field of view: 0.86 mm. Photomicrograph by Nathan Renfro.
One possible explanation for the unusual zoning is that compressional geological forces caused shearing along the emerald crystal’s basal plane. This was supported by the appearance of pyrite grains, which looked as if single, brittle pyrite crystals had been sheared and slightly displaced parallel to the basal plane of the beryl host (figure 2). This apparent lateral shearing movement throughout the emerald crystal could have caused the pyrite grains to separate into aligned tabular fragments offset from each other and the beryl host. Also observed between the pyrite grains were planar optical irregularities. These planes suggested localized shear zones that would have significantly higher defect concentration, giving rise to the optical nonconformity consistent with their location between the tabular pyrite inclusions. Under cross-polarized illumination, we observed dense clusters of birefringent crystals that were essentially invisible under non-polarized lighting. The low relief of these dense inclusions suggested they were beryl inclusions within the beryl host, possibly a result of partial recrystallization caused by dynamic environmental conditions.
Gemology is generally a non-destructive, observational science, which can be limiting at times. Destructive techniques could have revealed the crystallographic orientation of the pyrite grains with respect to each other and explained the stone’s unusual structure. Because this was a unique sample, destructive testing was not a practical approach. While the exact cause of this unusual zoning remains unknown, it is certainly interesting and thought provoking.The discovery of such gems demonstrates that there are complex geological conditions we do not yet understand which, when observed, invite further gemological exploration. Source: GIA @topic:2


Title: Prasiolite with Inclusion Influenced by Brazil-Law Twinning Abstract: Figure 1. Between crossed polarizers, the prasiolite showed two sections of Brazil-law twinning in the optic-axis direction. Photo by Meenakshi Chauhan, magnified 15×.

              The Indian Gemological Institute Gem Testing Laboratory recently examined a 6.43 ct transparent grayish yellowish green oval mixed-cut specimen. Standard gemological examination gave an RI of 1.545–1.553 with a uniaxial positive optic sign and a birefringence of 0.008, and a hydrostatic SG of 2.65. These readings readily identified the stone as prasiolite, a green variety of quartz.

The prasiolite displayed prominent Brazil-law twinning, with very sharp twinning planes when the sample was observed parallel to the optic axis between crossed polarizing filters, though only two sections of twinning were clearly visible in the stone (figure 1). The presence of such sharp and prominent Brazil-law twinning confirmed the sample’s natural origin. When synthetics do exhibit such patterns, it has a flame-like or irregular shape (J.I. Koivula and E. Fritsch, “The growth of Brazil-twinned synthetic quartz and the potential for synthetic amethyst twinned on the Brazil law,” Fall 1989 G&G, pp. 159–164).

Magnification showed no inclusions, but illumination from the side using a fiber-optic light source revealed minute white particles that scattered the light (figure 2). These pinpoint inclusions followed the pattern of the Brazil-law twinning, which was apparent without the aid of polarized filters (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones Volume 2, Opinio Verlag, Basel, Switzerland, 2005, p. 573).

	Figure 2. Fine dotted inclusions demonstrated a Brazil-law twinning pattern along the optic axis, exactly where this twinning was visible under polarized filters. Photo by Meenakshi Chauhan, magnified 10×.
Minor rhombohedron faces that did not feature Brazil-law twinning were filled with these minute light-scattering particles. These inclusions were visible on the faces with some tilting of the fiber-optic light source but did not show any pattern (figure 3). The minute particles were not visible in both zones simultaneously.

	Figure 3. Fine dotted inclusions were visible in this minor rhombohedral face where Brazil-law twinning was absent. Photo by Meenakshi Chauhan, magnified 10×.
In diffused transmitted light, the minor rhombohedron faces displayed a slightly darker shade of the grayish yellowish green color seen in prasiolite. These faces also showed a wavy internal growth structure between crossed polarizers. The major rhombohedron faces were even lighter in color. No color bands were observed in the stone.

Although the owner claimed the stone’s color was natural, the presence of Brazil-law twinning raised suspicion, since this twinning has only been associated with the amethyst variety of quartz. There is still no way to separate naturally heated from heat-treated prasiolite. Source: GIA @topic:2


Title: Imitation Moldavite Abstract: Figure 1. Acid-etched flow lines on artificial glass imitating moldavite. Photomicrograph by Michaela Stephan; field of view 2.34 mm.

Recently GIA’s Carlsbad laboratory received for identification a 46.13 ct yellowish green rough stone. The lack of a polished flat surface prevented a refractive index reading, while the specific gravity was measured as 2.45. Under microscopic examination, very few gas bubbles were found and some straight, approximately evenly spaced surface features were observed (figure 1).

Figure 2. Natural flow lines on moldavite. Photomicrograph by Michaela Stephan; field of view 7.19 mm.
Closer examination revealed these features were likely artificially acid-etched flow lines. The presence of gas bubbles coupled with flow lines led the author to infer an artificial glass or a natural glass, possibly moldavite, though moldavite has more natural-looking flow lines (figure 2). The SG reading was also slightly higher than the expected SG of 2.36 for moldavite. Additionally, moldavite typically contains numerous gas bubbles. Suspecting an artificial glass, the author analyzed the stone with a Fourier-transform infrared (FTIR) spectrometer. The FTIR reading showed absorption bands at approximately 2900 and 3480 nm, which confirmed an artificial glass.
Moldavites are a form of tektite, an impact glass created by the melting of rock caused when a meteorite strikes the earth’s surface. The most famous moldavites, found in southern Bohemia in the Czech Republic, were formed by the impact of the meteor that created the Ries crater 500 km away in southern Germany 14.7 million years ago. With rising prices for moldavite over the past few years, moldavite imitations have become more prevalent (Spring 2015 Gem News International, pp. 103–104). Source: GIA @topic:2


Title: Unusual Purple Inclusion in Emerald Abstract: Figure 1. This 7.11 ct emerald contains a large purple inclusion visible under the table. Photo by C.D. Mengason.

	Depending on geographic locality, inclusions in emerald are typically similar from one stone to the next. We expect to see classic jagged three-phase inclusions in Colombian emeralds or blocky multiphase inclusions and phlogopite in Zambian emeralds, so it is always interesting for the gemologist to observe something out of the ordinary. The Carlsbad laboratory recently examined a 7.11 ct oval mixed-cut emerald (figure 1), identified by standard gemological testing. Microscopic examination revealed jagged to irregular multiphase inclusions, planes of reflective thin films, clarity-enhanced fractures, and—surprisingly—a fairly large purple inclusion with a subhedral form. Upon closer examination, distinct purple and near-colorless banding was visible (figure 2), and the inclusion proved to be singly refractive when viewed between crossed polarizers. The inclusion was too deep within the stone to confirm its identity with Raman spectroscopy, but its appearance and optic character pointed to fluorite. Based on these characteristics, another possible identity could be halite, but this inclusion strongly resembled a color-banded fluorite inclusion previously reported in emerald by GIA’s laboratory in 1969. In that example, the surface-reaching inclusion was identified by scraping a sample and analyzing it with X-ray diffraction (R.T. Liddicoat, “Developments and highlights at the Gem Trade Lab in Los Angeles,” Summer 1969 G&G, p. 63).

Figure 2. With microscopic examination, clear purple banding is apparent within this fluorite inclusion. Photomicrograph by Jonathan Muyal; field of view 2.34 mm.

	Fluorite inclusions in emerald have been cited from various localities, as a product of pegmatitic/hydrothermal involvement in formation (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Vol. 3, Opinio Verlag, Basel, Switzerland, 2008, pp. 354–406; D. Schwarz et al., “Emerald and green beryl from Central Nigeria,” The Journal of Gemmology, Vol. 25, No. 2, 1996, pp. 117–141). These inclusions are usually described as colorless octahedra, although sometimes they are seen as cubes or rounded shapes. Purple banded fluorite is an unusual inclusion in emerald, making this an interesting and unexpected addition to an otherwise typical inclusion scene. Source: GIA @topic:2


Title: Large Star Emerald Abstract: Figure 1. A weak, six-rayed star is visible in this 25.86 ct emerald cabochon. Photo by Robert Weldon/GIA, courtesy of Manuel Marcial de Gomar.

	Star emeralds are rare specimens, and most are found in either Brazil or Madagascar. In 1999, Manuel Marcial de Gomar (Key West, Florida) purchased a 1,000-carat parcel of rough emeralds from Diallo Mahmoud, an independent emerald dealer based in Africa. Mahmoud noted that the parcel came from Madagascar. Marcial de Gomar later noticed that some crystals showed indications of chatoyancy. He chose this particular piece thinking it could be cut to produce a cat’s-eye emerald. Miami-based cutter Jone Ribeiro cut the stone into a 25.86 ct double cabochon (figure 1). Marcial de Gomar put the stone into his personal collection, where it stayed for 13 years, until independent gemologist and appraiser Martin Fuller examined Marcial de Gomar’s collection in 2013. Both experts recognized that this emerald was a star and not a cat’s eye. It was subsequently sent to GIA’s Carlsbad laboratory for an identification report.

Figure 2. Minute fluid inclusions oriented parallel to the basal plane of the crystal are the cause of this emerald’s asterism. The inclusions exhibit thin-film interference, causing rainbow colors that are visible at high magnification. Photo by Nathan Renfro; field of view 1.8 mm. Courtesy of Manuel Marcial de Gomar.

	The stone is described as an oval double cabochon natural star emerald. The asterism was caused by minute hexagonal fluid inclusions oriented parallel to the basal plane of the crystal (e.g., Spring 2004 GNI, p. 104; K. Schmetzer, et al., “Asterism in beryl, aquamarine, and emerald—an update,” Journal of Gemmology, Vol. 29, No. 2, 2004, pp. 66–71). They exhibit thin film interference with direct, pinpointed light that caused the asterism, as well as rainbow colors seen at high magnification (figure 2). Prior to this report, very few asteriated emeralds were recorded (e.g. Fall 1995 GNI, p. 206; Spring 1995 GNI, pp. 60–61; Spring 2002 GNI, p. 104; Summer 2006 GNI, pp. 171–172). This is the eleventh, and largest, star emerald known to date. Source: GIA @topic:3


Title: Unusual Optical Effect in Blue Sapphire Abstract: Figure 1. This 1.36 ct light bluish violet sapphire displayed an interesting color shift when exposed to the UV radiation of the DiamondView. Photo by Igor Iemelianov; magnified 15×.

              A 1.36 ct light bluish violet sapphire (figure 1) was presented to the laboratory of the State Gemological Center of Ukraine for examination. The stone exhibited an RI of 1.762–1.770, with a birefringence of 0.008, and a hydrostatic SG of 3.97. The samples displayed typical pleochroism and a very weak pinkish orange fluorescence to long-wave UV. Qualitative analysis using EDXRF spectroscopy showed major amounts of Fe, Cr, and Mg, and minor amounts of Ti and Ga. Microscopic examination revealed dot-like dissolved rutile, proof of heat treatment. The sapphire showed a small color shift from bluish violet in the daylight to pale blue in incandescent light. A band with pink luminescence (apparently due to Cr3+ impurity) was identified using the DiamondView (figure 2). When removed from the DiamondView, the stone had completely changed color to brown (figure 3, left). After about 15 minutes in natural daylight, the light bluish violet hue began to return (figure 3, right). About 12 hours later, its original blue-violet color was restored. Such color instability is extremely unusual in blue sapphires.

	Figure 2. The DiamondView recorded this band with pink luminescence in the light bluish violet sapphire. Image by Igor Iemelianov.

	Figure 3. When removed from the DiamondView, the sapphire had completely turned brown (left). After about 12 hours, the stone reverted to its original light bluish violet color (right). Photos by Igor Iemelianov, magnified 15×.
It should be noted that the UV lamp in the DiamondView has a wavelength less than 225 nm (according to the user’s manual). The energy of UV radiation is considered too weak for the color treatment of corundum (see K. Nassau, Gemstone Enhancement, Butterworth-Heinemann, 1984, p. 221). In this sapphire, the DiamondView apparently caused the color change. Such a reversible change of color with exposure to light is called photochromism. Source: GIA @topic:3


Title: Cat’s-Eye Kornerupine Abstract: Figure 1. This 1.44 ct yellowish green kornerupine displayed strong chatoyancy. Photo by Sood Oil (Judy) Chia.

A dark, translucent, yellowish green oval cabochon (figure 1) was recently submitted to the New York lab for identification. The 1.44 ct stone displayed an intense chatoyancy. With a spot refractive index reading of 1.67 and a hydrostatic specific gravity of 3.32, the stone was identified as kornerupine, a rare borosilicate mineral found in boron-rich volcanic and sedimentary rocks that have undergone metamorphism (http://rruff.info). Raman spectroscopy confirmed the identification.

Cat’s-eye kornerupine is an extremely rare gemstone. Its chatoyancy is caused by rutile and graphite inclusions (H.N. Lazzarelli, Gemstones Identification: Blue Chart, 2010, www.gembluechart.com). However, we were unable to identify the needles in this stone using Raman spectroscopy. Fiber-optic illuminated magnification exposed dense clusters of these needles, some displaying iridescence (figure 2). This was GIA’s first encounter with this material in more than a decade.

Figure 2. A dense collection of needle inclusions was the cause of the chatoyancy.
Photo by Daniel Girma; field of view 2.08 mm. Source: GIA @topic:2


Title: Green Sapphire Filled with Glass Abstract: Figure 1. This 1.83 ct specimen proved to be a manufactured product consisting of lead glass and natural green sapphire. Photo by Robison McMurtry.

              In recent years, one of the most problematic gem treatments has been the filling of ruby with lead glass, due to its unstable nature. In 2007, a new application for lead glass treatment in corundum began to appear in the market: sapphire filled with cobalt-colored lead glass (T. Leeawatanasuk et al., “Cobalt-doped glass-filled sapphire; an update,” The Australian Gemmologist, Vol. 25, No. 1, 2013, pp. 14–20). Recently examined at the Carlsbad laboratory was a particularly unusual 1.83 ct green sapphire (figure 1) that proved to be filled with a significant amount of lead glass.

Standard gemological testing gave an RI of 1.762–1.770, a hydrostatic SG of 4.00, a prominent absorption band at 450 nm, and inert reaction to long- and short-wave UV. These properties are consistent with natural corundum. Microscopic examination, however, revealed numerous low-relief cracks throughout the stone that showed a prominent blue flash effect, as well as several flattened gas bubbles trapped within the filler (figure 2). Also observed were reflective rutile needles.

	Figure 2. Flattened gas bubbles and a blue flash effect suggest that this stone contains significant amounts of lead glass, which was confirmed by EDXRF spectroscopy. Photo by Phil York; field of view 1.57 mm.
To determine if a leaded glass was used to hide the cracks in the corundum, we applied EDXRF spectroscopy, which confirmed the presence of lead. UV-visible spectroscopy was used to explore whether the color was intrinsic to the corundum (as in glass-filled ruby) or intrinsic to the filler glass (as in sapphire filled with a lead glass colored by cobalt). The UV-Vis spectrum revealed a prominent 450 nm series related to Fe3+ pairs responsible for the yellow component of the green color, which was consistent with the overall green bodycolor of the stone. The blue component was observed as diffuse planar color zoning unrelated to the network of fractures. This combination of natural yellow and blue components produced the overall green bodycolor.

This was the first lead glass–filled green sapphire examined at the Carlsbad laboratory. On a GIA identification report, this would be called a “manufactured product." Source: GIA @topic:3


Title: Aquamarine Description Abstract: An aquamarine crystal in its natural state shows why these specimens are prized for their beauty. - Courtesy Daniel Trinchillo, Fine Minerals International

                      Aquamarine is the green-blue to blue variety of the mineral beryl. (Emerald is the green to bluish green variety of the same mineral.) Its color is usually a light pastel greenish blue.

	This 20.83-carat stone from Africa represents the large size and attractive color that make aquamarine a much-prized gem. - De'ev Dvir/ICA, courtesy Gemstar Ltd., Israel
Heat treatment usually gives it a more bluish appearance.

Aquamarine crystals are known to be large in size and relatively clean and well-formed, making them particularly valuable to collectors of mineral specimens. Source: GIA @topic:3


Title: Cat’s-Eye Phenakite Abstract: Figure 1. This 38.34 ct phenakite showed a well-defined cat’s eye when viewed with point-source illumination. Photo by Kevin Schumacher.

While the beryllium silicate phenakite is known to gemologists both as a by-product inclusion in synthetic emeralds and in association with natural beryllium-containing gems such as emerald and chrysoberyl (see Fall 2003 Gem News International, pp. 226–227), it is rarely encountered in the laboratory as a fashioned gemstone. Although phenakite does occur in nature as transparent pegmatitic crystals from localities such as Brazil, and as alluvial stream-rounded Sri Lankan pebbles suitable for cutting, such gems are generally considered collector curiosities and are not often submitted to gemological laboratories for identification. Therefore, any occasion to document such a rare and unusual gem material is always of interest, especially if it also displays an optical phenomenon.

We recently had the opportunity to examine a large colorless cabochon represented as phenakite that was provided for examination by Elaine Rohrbach of GemFare in Pittstown, New Jersey. This gem measured approximately 18.19 × 17.77 × 14.81 mm, weighed 38.34 ct, and was transparent to the unaided eye. Although it appeared to be essentially transparent, it also showed relatively strong chatoyancy (figure 1) in the form of a sharp eye extending across the dome of the cabochon when illuminated from above with a single light source, such as sunlight or a fiber-optic illuminator. This gem was said to be from Sri Lanka; while gem-quality Sri Lankan phenakite is known to contain “needle-like” inclusions, chatoyancy is not specifically mentioned as a phenomenon in major gemological reference books such as Robert Webster’s Gems or Joel Arem’s Color Encyclopedia of Gemstones.

Numerous minute acicular tubes and platy voids were clearly seen under 30× magnification using fiber-optic illumination. These inclusions were all aligned parallel to the optic axis, which was oriented in a plane parallel to the cabochon’s base and perpendicular to the reflective chatoyant band (figure 2). Under 90× magnification, some of the iridescent platy voids displayed complex multi-component interiors. The various components showed contrasting iridescent colors, which made them stand out from their surroundings. The examination demonstrated that light reflections from the numerous tubes and the iridescent voids were responsible for the pronounced chatoyancy in this phenakite cabochon. Because they were only clearly visible when illuminated from overhead, these inclusions created an interesting balance between transparency and chatoyancy that is rarely seen in gems displaying cat’s eyes. Very few phenakites have been examined by GIA, which makes this example of a chatoyant variety a very exciting experience.

Figure 2. Viewed using oblique fiber-optic illumination, some of the iridescent platy voids
in the phenakite contained complex multi-phase components consisting of a liquid, gas,
and solid daughter crystals. Field of view 0.90 mm. Photomicrograph by John I. Koivula.
It is interesting to note that another cat’s-eye phenakite was reported on in G&G’s Fall 2009 GNI section. Unlike the transparent, colorless gem reported here, that stone had a light brownish yellow color and was discovered in Madagascar. This author was reminded somewhat of the initial discovery of another gemological rarity, sapphirine, which was completely unknown to gemologists until it was identified within a short period from Australia, Kenya, Thailand, and Sri Lanka. As the world’s population grows and we search the earth’s surface for gems, more places will be more thoroughly explored and in turn new discoveries will be made. Source: GIA @topic:3


Title: Small “Surprise” in Elbaite Tourmaline Abstract: The “exclamation point” inclusions were identified as diopside crystals using Raman spectroscopy. Photomicrograph by Shu-Hong Lin; field of view 4.11 mm.
Recently, a 0.86 ct orange-yellow elbaite tourmaline cabochon was submitted to Taiwan Union Lab of Gem Research (TULAB) for identification service. The stone contained many prismatic and round xenocrysts. Among these inclusions was a prismatic crystal associated with a round crystal, a composition resembling an exclamation point (see above). The crystals were later confirmed to be diopside using Raman spectroscopy. Darkfield illumination, plane polarized light, and extended depth of field were adopted to obtain a clear microscopic image of this little “surprise” inside the gemstone. Source: GIA @topic:2


Title: Update on Ammolite Production from Southern Alberta, Canada Abstract: There have been a number of changes in Ammolite production from southern Alberta, Canada, since 2001. Korite International continues to be the dominant supplier, with a 40% increase in finished-stone production during this period. As mining focuses on Zone 4 of the host Bearpaw Formation, Korite’s inventory has changed from predominantly fractured to sheet Ammolite. The Aurora Ammolite mine, operated by Rusty Pimm Enterprises, is the only other fully mechanized open-pit mine, but artisanal miners continue to be active. Dinolite—Ammolite combined with siliceous dinosaur bone—has been introduced as yet another innovative use for Ammolite.

	DATA DEPOSITORY

Additional Photos
	Fall, 2009 Source: GIA @topic:1


Title: Alumni: 2015 in Review, Anticipation for the Year Ahead Abstract: Sri Lanka chapter hosts GIA Field Gemology Team members in Columbo, Sri Lanka for talk on “Rubies from Zahamena National Park, Madagascar.” Photo by Didier Barriere Doleac/GIA

As we emerge from the blur of year-end and jump into the New Year, I like to take time to recognize the previous year’s accomplishments and successes. It’s also a great time to set the stage for new goals to support our alumni members around the world.

I am excited to say that 2015 was another stellar year of milestones and highlights − and is going to be hard to top. It would be nearly impossible to summarize all of the accomplishments of our global alumni and chapters, or the effect of their outreach as ambassadors supporting GIA’s mission, so I’ve highlighted a few to showcase the actions of our dedicated alumni around the world.

	2015 Retrospective

Highlights

		A new milestone: There are more than 110,000 active GIA Alumni members.

Global chapters: 72 GIA Alumni Association chapters exist on five continents.

Chapter Events exceeded 200, offering continuing education and networking opportunities for alumni, students and industry members worldwide.

		GIA connected with our alums at nearly 100 tradeshows in 2015!

Alumni Online Directory: More than 3,000 new members listed their information on GIA’s website to make their credentials and contact information available to the public. All alumni members can be included in this directory.

		Nearly 1,500 members took a moment to manage their alumni membership and let GIA know which alumni benefits are important to them.

	The Hong Kong chapter hosted a full session for a guest lecturer on “Intro to the World of Jewelry Photography.” Courtesy of the Hong Kong chapter
In Review

GIA chapters did not slow down − even in our industry’s busy fourth quarter. Chapters delivered education sessions, social events and gemological updates to their members. In fact, more than 22 events took place since my last report. It always amazes me to see just how much has occurred. Here are some of the chapter news and events that have occurred since early November:

		The Cincinnati winter social successfully gathered chapter members and affiliates from their event co-hosts: WJA and AGS.

Golden Gate hosted award-winning lapidary John Noel Soni, who shared his passion as a self-taught artist, travel experiences, sourcing and the importance of well-cut gemstones.

Golden Gate and Washington D.C. expanded their knowledge on watches by attending a special exhibition on Breguet, which was hosted watch expert Gary Lester.

Hong Kong hosted an “Intro to the World of Jewelry Photography.” More than 300 attended their annual banquet and chapter elections.

Johannesburg focused on the “Lure of Rubies, Emeralds and Sapphires” with attendees.

London and Louisiana gathered for socials and focused on growing their chapter’s leadership by asking members to become involved.

		The Los Angeles mega-mixer was attended by more than 200 industry members from four prominent industry organizations in Southern California.

		The Manhattan holiday gathering focused on charitable giving and featured David Rocha, executive director of Jewelers for Children.

Monterrey, Mexico chapter leadership presented chapter lectures on emeralds and birthstones.

Ontario, Canada and Switzerland meet and greet socials connected members of local alumni and industry networks.

San Diego hosted GIA’s Dr. Tao Hsu and Andy Lucas for an overview of Mine to Market in the colored gem trade. They also shared first-hand experiences from their field gemology research travels.

South Florida and Golden Gate meetings focused on educational presentations on archaeogemology by Dr. Cigdem Lule and the “History of the Diamond Market” by Jon Phillips.

Spain and Portugal alumni gathered in Lisbon for a presentation by GIA’s Edward Johnson, director of global business development (Europe).

Switzerland members had the rare opportunity to tour of the Gübelin Gem Lab and hear a lecture from its managing director Dr. Daniel Nyfeler on the age of gemstones.

Sri Lanka successfully hosted GIA Field Gemology Team representatives for an update on research news from recent excursions to colored gemstone localities.

		The Taiwan holiday gala included education, networking and sharing the chapter’s rich history.

Twin Cities continued their successful chapter “hands-on” lab study sessions.

Washington D.C.’s annual holiday party and auction raised more than $6,000 to support the chapter and provide opportunities to offer more than 10 education events each year.

	Washington D.C. members Martin Fuller and Joanna Athanasopoulos share their holiday spirit at the annual chapter auction and year-end celebration. Courtesy of the Washington D.C. chapter

	Looking Ahead in 2016

As you will see below, we are already on the path to an exciting and bright launch to 2016 with the activities and announcements below.

GIA Events
Tucson’s gem, mineral and jewelry fairs will soon take place and GIA’s presence and activities are extensive. Gem and mineral enthusiasts from across the globe gather at the more than 40 concurrent shows that take over the town. We hope to see you there!

Party at the GIA Gem Mine: Arctic Blast is coming up in early February and you’re invited. It is a guaranteed night of fun at this annual dinner, dance and auction. Hosting more than 350 alumni, students and industry friends, it’s a reunion celebration.

		GIA will be present at 14 trade fairs in the first few months of 2016. Visit our representatives at shows in Bangkok, Istanbul, Johannesburg, Tokyo and multiple shows across India and the U.S. to find out the latest on GIA education, offerings and news.

		Show Service Laboratories will be available at Basel, Hong Kong, Tokyo and Tucson, offering GIA laboratory colored gemstone identification services on site.

In summary - BRAVO! It’s exciting to see so many accomplishments and the actions of industry professionals who take advantage of the GIA Alumni Association’s network and benefits. And, a reminder to those who have haven’t made the most of their affiliation, it’s never too late to start.

I send a special thank you to the committed alumni member participants and volunteer chapter leaders around the globe for supporting GIA’s mission to promote education and integrity across the gem and jewelry industry.

I look forward to the year ahead and supporting the efforts and needs of our alumni across the globe. Source: GIA @topic:9


Title: Winter 1986 G&G Book Reviews Abstract: “Natüraliche und Synthetische Rubine”
By Karl Schmetzer, 131 pp., illus., publ. by E. Schweizerbart'sche Verlagsbuchhandlung,
Stuttgart, West Germany, 1986. US$22.50

“The Magic of Minerals”
By Olaf Medenbach and Harry Wilk, transl. by John S. White, 239 pp., illus., publ. by Chilton Book Co., Radnor, PA, 1986. US$35.00

“Descriptions of Gem Materials”
By Glenn and Martha Vargas, 190 pp., publ. by the authors, Thermal, CA, 1985. US$10.00

“Jewelry: How to Create Your Image”
By Jorge Miguel, 119 pp., illus., publ. by Taylor Publishing Company, Dallas, TX. US$19.95

“The New Jewelry: Trends & Traditions”
By Peter Dormer and Ralph Turner, 192 pp., illus., publ. by Thames and Hudson, New York,
NY. US$35.00

“Opals: Rivers of Illusions”
By Alina Loneck, 64 pp., illus., publ. by Gemcraft Pty Ltd., East Malvern, Victoria, Australia, 1986.
US$6.95

“Treasures of the British Museum”
By Mariorie Caygill, 240 pp., illus., publ. by Harry N. Abrams, Inc., New York, NY, 1985. US$29.95

”A Time to Watch”
By Jac Zagoory and Hilda Chan, 200 pp., illus., publ. by ChiuZac Ltd., New York, NY, 1985. US$88.00.

“Struck by Lightning”
by Les Taylor, 183 pp., illus., publ. by Jon the Printer Pty. Ltd., Ashmore, Queensland, Australia, 1985. US$10.00 (approx.)

To view the full section, download the PDF above. Source: GIA @topic:10


Title: Trapiche-Type Sapphire from Tasmania Abstract: Figure 1. Production from one day of mining in Tasmania. The trapiche-type sapphire in the center weighs 2.73 ct. Photo by Vincent Pardieu/GIA.

	Trapiche and trapiche-type minerals are treasured for their beauty and unique patterns. The six-rayed spoke patterns occur in different minerals but are best known in emeralds. During a GIA field expedition to the Australian island of Tasmania, author VP was able to mine several sapphires (figure 1), including a black star, some small blue samples, and a 2.73 ct blue sapphire that showed a fixed six-ray pattern. Trapiche-type stones are found in almost all basalt-related sapphire fields, but they are considered exceptionally rare in Tasmania (B. Sweeney, “Interesting gems from north-east Tasmania,” Australian Gemmologist, Vol. 19, No. 6, 1996, pp. 264–267).

	The trapiche-patterned stone had a dark blue bodycolor and was translucent to opaque. Many inclusions were visible, as were iron-stained fractures and clouds of particles. Hexagonal growth and color zones could also be seen. The core of the sample appeared colorless. The trapiche pattern was expressed as a hexagonal core with six radiating arms (figure 2). These white reflective features stood out against the blue bodycolor. The stone weighed 2.54 ct after we opened a polished window, and it measured approximately 6.93 × 8.20 × 3.00 mm after fabrication.

	Figure 2. The polished section of the trapiche-type sample, as seen with fiber-optic illumination. The central white core and the six whitish particle-rich arms separated by blue areas are clearly visible. Photo by Victoria Raynaud.

	The relationship of the trapiche arms to the color zoning is important for correctly identifying a sample as “trapiche” or “trapiche-type.” In this case, it was obvious that the rays were perpendicular to the hexagonal color and growth zoning, and that the intersections were not located at the corners of the hexagonal pattern.

	According to the recent literature, this pattern would not qualify as true trapiche, as seen in Muzo emeralds or some Mong Hsu rubies (G. Giuliani and I. Pignatelli, “‘Trapiche’ vs ‘Trapiche-like’ textures in minerals,” InColor, Vol. 31, 2016, pp. 45–46). True trapiche minerals have equivalent, crystallographic sectors divided by heavily included zones, a pattern expressed as arms intersecting the growth patterns at the junctions (figure 3, left). In the Tasmanian sapphire, the included zones were perpendicular to the growth zones and did not divide the gem into crystallographic sectors (see figure 3, right). Thus, it was a “trapiche-like” mineral.

	Figure 3. Trapiche (left) and trapiche-type (right) patterns in corundum.

	The sample’s chemical composition was analyzed with laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) on five different areas. The trace-element composition was analyzed in the white core, two arms at mid-length, one arm close to the core, and a blue area between the arms (again, see figure 2).

	For most elements (Mg, V, Fe, Zr, Nb, and Ta), an increase in concentration is observed from the less included blue areas to the most included area, which was the core. Ti showed a different pattern, with higher concentrations in the arms and lower concentrations in the blue areas; concentrations were even lower in the core. Ga remained constant throughout the stone but was slightly elevated in the core. Be showed a similar pattern but was more variable outside the core.

	The higher concentration of certain elements (V, Zr, Nb, and Ta) was most likely due to the presence of microinclusions. Ti was extremely low in the core, where there was no blue color; higher Ti concentrations in the other areas explained the blue color. The variation within the arms and the blue area may be explained by growth + color zoning, although the influence of Ti-rich particles should not be excluded. The Fe concentrations were probably caused by a combination of increased particle density and internal growth variations. It is notable, but not unexpected, that this natural trapiche-type sapphire contained some Be, albeit in very low quantities (V. Pardieu, “Blue sapphires and beryllium: An unfinished world quest,” InColor, Vol. 23, 2013, pp. 36–43). The Be concentration was highest in the core, where the particle density was highest and the blue color was absent.

	While trapiche-type sapphires are not particularly rare, it is unusual to find them in Tasmania. This sample has additional scientific value because it was mined by a field gemologist during a field expedition, giving it an extremely reliable origin. Source: GIA @topic:1


Title: Resin-Coated and Clarity-Enhanced Aquamarine Pendant Abstract: Figure 1. This 34.24 ct light greenish blue free-form aquamarine pendant, measuring 33.40 × 25.75 × 6.40 mm, was seen in the Carlsbad laboratory. Photo by Robison McMurtry. Stone courtesy of Stephen Challener.

The Carlsbad laboratory received a 34.24 ct light greenish blue free-form pendant (figure 1) measuring 33.40 × 25.75 × 6.40 mm. One side of the pendant was flat and polished, and the other side had a rough surface. Standard gemological testing gave a refractive index (RI) of 1.570–1.580. The pendant had the same reaction to long-wave and short-wave UV light: blue fluorescence in the center and green fluorescence around the edges of the stone. Examination with a standard gemological microscope revealed a blue and orange flash effect most clearly visible from the flat side (figure 2, left), which is diagnostic of clarity enhancement. Ultraviolet/visible/near-infrared (UV-Vis-NIR) spectra were consistent with natural aquamarine, with absorption peaks at 370 and 425 nm and an absorption band at ~830 nm (figure 2, right). Raman spectroscopy showed the presence of polymer on the rough side of the stone and aquamarine on the polished flat side. Although emeralds are the variety of beryl most commonly associated with clarity enhancement, filled aquamarine has previously been reported in the Chinese market (J. Li et al., “Polymer-filled aquamarine,” Fall 2009 G&G, pp. 197–199).

Figure 2. Left: The orange and blue flash effect seen in a clarity-enhanced fracture of the aquamarine. Photomicrograph by Michaela Stephan; field of view 4.24 mm. Right: The UV-Vis-NIR spectrum, with absorption peaks at 370 and 425 nm and an absorption band at ~830 nm, is consistent with natural aquamarine.

Figure 3. Left: Gas bubbles and high luster on the aquamarine’s resin-coated rough surface, shown near the drill hole. Photomicrograph by Michaela Stephan; field of view 7.19 mm. Right: The FTIR spectrum shows polymer peaks at ~3100–2850 cm–1. The dotted line is the spectrum of an untreated aquamarine, shown for reference.
Only one side, the rough side, was coated with polymer resin. Viewed in the microscope, this side appeared to have a thin transparent layer on the surface. Trapped air bubbles were visible with magnification (figure 3, left), and areas with the coating had a higher luster than the polished flat side. Fourier-transform infrared (FTIR) spectroscopy taken from the rough side revealed strong diagnostic peaks at ~3100–2850 cm–1 (figure 3, right).
Although clarity enhancement and coating of beryl gemstones are not uncommon, this material is rarely seen in a gemological laboratory. Both treatments are readily identified, but careful examination of every stone is important to identify them. Source: GIA @topic:3


Title: Color Study of Fancy Sapphire from Greenland Abstract: Figure 1. Part of the suite of sapphires studied for this project (weighing 0.23–1.41 ct). Photo by Sasithorn Engniwat; courtesy of Greenland Ruby.
Over the past 70 years, several ruby and pink sapphire localities have been documented in the region of Greenland’s capital city, Nuuk (P.W.U. Appel and M. Ghisler, “Ruby- and sapphirine-bearing mineral occurrences in the Fiskenaesset, Nuuk and Maniitsoq regions, West Greenland,” GEUS, Geological Survey of Denmark and Greenland, 2014). Several of these localities are currently exploited on a small scale by the local communities. In 2017, Greenland Ruby A/S started a large-scale mining operation at the Aappaluttoq ruby and pink sapphire deposit, located 160 km south of Nuuk.
The corundum extracted at Aappaluttoq is heated in air at temperatures over 1500°C for several hours, with some flux added. In rare cases, the heating significantly alters the color of light pink and near-colorless sapphire, resulting in fancy-color sapphire. GIA recently studied a parcel of 22 of these fancy-color sapphires mined and treated by Greenland Ruby (figure 1).
A combination of ultraviolet/visible/near-infrared (UV-Vis-NIR) spectra and trace element chemistry using laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) were collected at GIA in Bangkok to identify the causes of color. For full quantification of the chromophores, it is necessary to do this analysis in oriented, clean samples with a known path length. Since most of the Greenland material is polished as cabochons and contains some inclusions, it is very challenging to calculate or even estimate the absorption coefficients. We limited ourselves to a rough interpretation of the chromophores based on the shape of the spectra. Orientation of the samples was estimated based on the pleochroism.
Additionally, we could not precisely identify which area of the stone was analyzed during the spectroscopy, and thus all UV-Vis spectra were bulk measurements and combined the color of different zones. In contrast, the LA-ICP-MS analysis was performed at very specific spots, allowing the analysis of specific zones.
The literature describes six chromophores responsible for color in natural corundum (E.V. Dubinsky et al., “A quantitative description of the causes of color in corundum,” Spring 2020 G&G, pp. 2–28). Four of the chromophores from that study are responsible for the colors in this suite.

Figure 2. A UV-Vis-NIR spectrum dominated by Cr3+ features often results in a pink to red stone, depending on the concentration of Cr3+ (in ppma). When the sample is oriented down the c-axis, the color often trends toward reddish purple (i.e., fancy sapphire).
Most stones from the Aappaluttoq deposit are colored by the Cr3+ chromophore, giving them their typical pink to red color (figure 2). The intensity of the color is directly linked to the concentration of Cr3+, which can go up to several 1000 ppma, and in exceptional cases even to 15,000 ppma. Most of the lighter-colored material has a concentration of a few 100 ppma, resulting in a pink color.

Figure 3. The peaks at 550 and 430 nm in the o-ray spectrum (black) suggest the presence of Cr3+, causing pink to red in the stone. The trace element analysis (in ppma) shows a clear excess of Mg2+ compared to the Ti concentration, highlighting that trapped hole creation is very likely. When we remove the absorbance spectrum of Cr3+ from the stone’s absorption spectrum (blue), it is obvious that the combination of Cr3+ with the trapped hole is the cause of the remaining color and the strong orange tint observed in the stone.
Depending on the orientation, it can appear more purple (when viewed through the c-axis). In some cases, this is so strong that the face-up color of the stone is modified to an extent that it cannot be defined as ruby or pink sapphire and falls into the fancy reddish purple range. Some of the stones develop a more orangy tone after treatment. (A bright orange oval brilliant seen at the 2023 Tucson shows is highlighted in this issue.) This color can be attributed to the creation of trapped holes in combination with Cr3+ (figure 3).
To create trapped holes, the chemical balance in the stone needs to be correct. Only when a stone is acceptor dominated will trapped holes be present. In the case of Greenland ruby, this comes down to the balance between Mg2+ vs. Ti4+, Si4+, and H+. Since the stones have all been treated in air (oxidizing atmosphere), we can assume that H+ has diffused out of them. With the method used to measure trace elements (LA-ICP-MS with a quadrupole MS), we cannot correctly quantify the Si4+ content in these stones. The possibility that Si4+ plays a role in the color cannot be excluded. Regardless, there is no indication here that Si4+ is required to tilt the balance of chromophores when comparing trace elements vs. observed color. Since we do not aim to quantitatively analyze the color, we ignore any potential presence of Si4+. This means that the concentrations of Mg2+ and Ti4+ are the determining factors: Only if the amount of Mg2+ is larger than the Ti4+ concentration can trapped holes develop in sapphire from Greenland.
Two ions in sapphire can pair with trapped holes: Fe3+ and Cr3+. Since the trapped hole preferentially pairs with Cr3+, this is the chromophore observed in these stones. The quantity of trapped holes that can form in corundum is very low, and as such, not all the Cr3+ couples with a trapped hole. The final color will be a combination of the trapped hole color and the pure Cr3+ chromophore, resulting in a combination of pink to red and orange colors. Trapped holes are very strong coloring agents that can have a major impact even when their concentration is very low.

Figure 4. This plot shows the o-ray spectrum of a pale yellow sample (black) and a modified o-ray spectrum where some contribution by Cr3+ is subtracted (blue). When the Cr3+ spectrum is removed, a pure Fe3+ spectrum remains. This spectrum is characterized by the double peak at 377–388 nm and one at 450 nm. The ratio of the 388 to 377 nm band suggests a relatively low Fe3+ chromophore concentration, which matches the observed color and analyzed chemistry (in ppma).
The Fe3+ chromophore is the weakest one encountered in natural corundum. Very high concentrations of Fe3+ are required to create a yellow color, often exceeding several thousand ppma. Since the Greenland rubies have a maximum iron concentration under 1500 ppma, this chromophore creates only a very weak yellow color (figure 4). Other common chromophores are much stronger and more common, which makes it very difficult to notice any color contribution by Fe3+. Only when the Cr3+ concentration is extremely low can we detect the pale yellow color from the Fe3+ chromophore.

Figure 5. The extremely low Cr3+ contents allow other features to be dominant. In this case, Fe2+-Ti4+ charge transfers with a large peak at 580–620 nm are responsible for a blue color. The absorption spectrum of the stone also shows some features related to Fe3+, which is a very weak chromophore and does not influence the color.
The Fe2+-Ti4+ chromophore creates a blue color in corundum and is relatively strong (figure 5). When observed in ruby from Greenland, its effect is usually limited to a slightly increased purplish hue in the chromium-rich corundum, occasionally modifying the color to a dominant purple hue. Only when the Cr3+ concentrations are extremely low is there a chance for the corundum to have a blue color. We still observe some cloudiness after the treatment in the blue zones.
We assume that this type of rough corundum had a milky appearance caused by a high concentration of fine rutile particles before treatment. During treatment at temperatures over 1200°C, some of the particles dissolved into the lattice, becoming available to pair with Fe2+ that was already present and creating a blue bodycolor. Due to the large amounts of Ti4+ that diffused into the crystal lattice, the iron was forced to remain in a reduced state (Fe2+).
The nature of the treated corundum from Greenland makes high-quality spectroscopy a challenge. Nevertheless, we were able to isolate and identify the chromophores responsible for the fancy colors observed in these sapphires.
It is important to note that many of these fancy colors developed as a result of heat treatment. The trapped hole–related chromophores only become visible after H+ diffused out of the stone under oxidizing conditions. These same conditions also allow the iron to oxidize and create the pale yellow color by Fe3+ chromophores. The high temperatures were also required to dissolve rutile particles into the corundum lattice and form Fe-Ti pairs.
While these fancy-color stones remain a curiosity, they make for a welcome addition from a mine that is known for its ruby and pink sapphires. Source: GIA @topic:3