Title: Purplish Pink Diaspore Reportedly from Afghanistan Abstract: Figure 1. This purplish pink diaspore is reportedly from a new deposit in Afghanistan, discovered in February 2020. The faceted stones weigh 0.57 to 1.60 ct; courtesy of Donald Hofler. The rough stones range from 4.15 to 17.52 ct; courtesy of Salman Khan. Photo by Diego Sanchez.
Diaspore, an orthorhombic aluminum oxide hydroxide mineral with the formula AlO(OH), is a relative newcomer to the jewelry scene, with some stones possessing a captivating ability to change color between pale green, yellow, pink, and purple when viewed in different sources of light (C. Shen and R. Lu, “The color origin of gem diaspore: Correlation to corundum,” Winter 2018 G&G, pp. 394–403). Here we document a new find of purplish pink gem diaspore reportedly from Nangarhar Province, Afghanistan (figure 1).
Previously, transparent crystals of diaspore in sizes suitable for jewelry purposes were only recovered from mining operations on Ilbir Mountain near the village of Pinarcik, Milas District, Muğla Province, Turkey (M. Hatipoğlu and S. Chamberlain, “A gem diaspore occurrence near Pinarcik, Mugla, Turkey,” Rocks & Minerals, Vol. 86, No. 3, pp. 242–249). Gem diaspore from Turkey has been reported since the late 1970s (K. Scarratt, “Faceted diaspore,” Journal of Gemmology, Vol. 17, No. 3, 1980, pp. 145–148), but it was not until commercial mining began in 2005 that a consistent supply became available and was subsequently marketed under various trade names including Zultanite and Csarite (S. Kotlowski and L. Rosen, “A short history of diaspore and its trade names Zultanite and Csarite,” International Gem Society, www.gemsociety.org/article/short-history-diaspore-trade-names-zultanite-csarite). Additionally, alluvial deposits in Myanmar near Mong Hsu have yielded limited amounts of chromium-colored gem-quality crystals in small sizes since 2004 (U Hla Kyi and K.K. Win, “A new deposit of gem quality colour-change diaspore from Möng Hsu, Myanmar,” Australian Gemmologist, Vol. 22, No. 4, pp. 169–170).
Dealers Salman Khan (ARSAA Gems & Minerals) and Noshad (Noshad Gems Enterprises), both based in Peshawar, Pakistan, reported that in March 2020, a purplish pink diaspore from a new deposit had reached the gem market. The new material was reportedly coming from the Goshta district of Nangarhar Province near the village of Ragha. The authors obtained several samples from Salman Khan and Donald Hofler, a gem dealer in Texas, to perform gemological and advanced testing to characterize this material. These samples would be classified as F-type samples (collected in the international market) according to the classification scheme used by GIA’s field gemology department (W. Vertriest et al., “Field gemology: Building a research collection and understanding the development of gem deposits,” Winter 2019 G&G, pp. 490–511). It was also reported by the Peshawar-based dealers that preliminary experiments with gamma irradiation resulted in samples becoming an undesirable dark brownish orange color, but this was not tested further by the authors.

Figure 2. Microscopic examination of the diaspore revealed numerous elongate fluid inclusions (A) and planes of fluid inclusions (B). Also observed in two rough samples were fine black rutile needles (C), and one stone contained an unidentified brown hexagonal crystal (D). Photomicrographs by Nathan Renfro; field of view 1.88 mm (A), 1.44 mm (B), 4.47 mm (C), and 1.41 mm (D).
Microscopic examination showed that the dominant type of micro feature in the material is fluid inclusions, typically consisting of a gas bubble, liquid, and occasionally a solid phase. Fine curved black rutile needles were also observed in two of the samples (confirmed by Raman analysis), while one diaspore crystal contained a brown hexagonal crystal that the authors were unable to identify (figure 2). Brown epigenetic staining and cleavage cracks were observed in several samples. Strong doubling from birefringence was also characteristic of the material.
Gemological testing revealed a biaxial positive mineral with refractive indices of nα = 1.700, nβ = 1.721, and ng = 1.749, and a specific gravity of 3.38. The maximum birefringence observed was 0.049. Examination with a dichroscope showed three distinct pleochroic colors, consistent with a biaxial mineral: dark purplish pink, pale yellow, and pale pink. The diaspore showed a very weak red fluorescence under long-wave ultraviolet light and an irregular chalky yellow fluorescence reaction under short-wave UV. When the samples were examined with daylight-equivalent illumination and compared to incandescent illumination, a slight color shift was observed. The samples appeared less purplish, going from purplish pink in daylight-equivalent lighting to a nearly pure pink hue in incandescent lighting, but no distinct color change of the dominant hue was observed in the faceted samples.

Figure 3. UV-Vis-NIR spectra were collected from an optically oriented sample to resolve the alpha, beta, and gamma vibrational directions in the Afghan diaspore. All three spectra showed a broad absorption band centered between 560 and 580 nm resulting primarily from vanadium and chromium. In this sample, the average concentrations were 57 ppma vanadium, 20 ppma chromium, 205 ppma iron, and 84 ppma titanium.
Advanced spectroscopic instrumentation was used to further characterize the new diaspore material. One sample was optically oriented into a polished cube with parallel faces polished perpendicular to the crystallographic axes (T. Thomas et al., “Device and method of optically orienting biaxial crystals for sample preparation,” Review of Scientific Instruments, Vol. 85, No. 9, 2014, 093105). The ultraviolet/visible/near-infrared (UV-Vis-NIR) absorption spectra of the polished cube revealed broad absorption bands centered in the range of 560 and 580 nm for alpha, beta, and gamma polarizations (figure 3). Under daylight-equivalent lighting, the saturated purple-pink color was consistent with the alpha vibration direction, pale greenish yellow for the beta direction, and light purplish pink for the gamma direction. Under incandescent light, the pleochroic colors were saturated purple-pink for the alpha color, orange-pink for the beta color, and light pink for the gamma color. Color swatches were calculated using the measured spectra to produce a representative color for each pleochroic color and also to show how the colors mix relative to their crystallographic axes (figure 4).

Figure 4. One diaspore sample was fabricated into a crystallographically oriented block in order to measure the polarized spectra, which were used to analyze the color. This figure shows the relationship of the polarized spectra measured parallel to each crystal axis and the resulting colors produced when the polarized spectra are mixed together under daylight (top) and incandescent (bottom) conditions, which is what the viewer would observe using unpolarized light transmitted through the sample normalized to a 1 cm path length. Under daylight-equivalent lighting, the alpha color was saturated purple-pink, the beta color was light greenish yellow, and the gamma color was light pink. Under incandescent light, the alpha color was a saturated purple-pink, the beta color was orange-pink, and the gamma color was light pink. The acute 2V angle, or angle between the two optic axes, was measured as 85° in this sample. Both axes lie in the optic plane that is perpendicular to the b crystal axis.
Observations under the microscope showed the cleavage direction in the faceted stones to be nearly parallel to the table (it is inclined slightly, presumably to avoid cleaving when polishing the table facet). This orientation places the b-axis approximately perpendicular to the table facet, which will facilitate the best color face-up, composed primarily of a mixture of the alpha and gamma rays.

Figure 5. The purplish pink gem material from Afghanistan showed a Raman spectrum (left) that matched diaspore, with a dominant peak at 449 cm–1 and smaller peaks at 334, 500, and 669 cm–1. Its FTIR spectrum (right) was consistent with diaspore, with absorption features at approximately 2115 and 1990 cm–1 and broad absorption bands at approximately 4080 and 3000 cm–1.
Raman analysis confirmed the material’s identity as diaspore (figure 5, left). Fourier-transform infrared (FTIR) spectroscopy showed absorption features at approximately 2115 and 1990 cm–1 and broad absorption bands at approximately 4080 and 3000 cm–1, all of which are consistent with diaspore (figure 5, right). Chemical analysis of seven samples showed a bulk composition consistent with that of diaspore, and average notable trace element concentrations showed 27 ppma chromium (ranging from 14 to 48 ppma), 31 ppma vanadium (from 14 to 59 ppma), 213 ppma titanium (from 67 to 428 ppma), and 252 ppma iron (from 137 to 350 ppma).
This exciting discovery of purplish pink diaspore from Afghanistan may prove to be a significant new deposit. While production volume is currently unknown, several kilograms of material have been reported and large faceted stones of nearly 50 ct have been described on social media (Mark Smith, @thailankagems). The color of this diaspore can be attributed mainly to trace element concentrations of chromium and vanadium. The concentrations of these elements are generally different from those in Turkish diaspore, which has significantly lower vanadium, and those in Burmese material, which generally has much higher chromium. This new attractive color of gem-quality diaspore will certainly be a welcome addition to the gem trade. Source: GIA @topic:1


Title: Fossil Ivory Update with Lee Downey Abstract: Figure 1. Fossil walrus ivory carvings by Artifactual. The base of the octopus carving is chalcosiderite. Photos by Kevin Schumacher.
Lee Downey, owner of Artifactual (Tucson, Arizona), spoke with us in early 2020 about his 35 years in the fossil ivory carving trade and the impact of ivory bans on his business. Until recently Downey carved fossil ivory from mammoth and walrus tusks thousands of years old; he has never used elephant ivory. But legislative measures banning all ivory in response to the poaching of African elephants have diminished ivory demand.
Downey got his start in silver and turquoise and established Artifactual in the late seventies. Since then, he has lived and worked in an ivory carving village in Bali with artisans he calls “the most talented carvers in the world.” When he first arrived in Bali, they were carving bone and coconut shell. His task was to carve animals and animal skulls out of fossil ivory. “We created a trade,” he said. He showed us two of Artifactual’s current offerings (figure 1). “But now the material has become flat-out illegal in eight states.”
Since 2014, California, Hawaii, Illinois, Nevada, New Hampshire, New Jersey, New York, and the District of Columbia have enacted prohibitions against trade in ivory. (Two other states, Oregon and Washington, have banned only ivory from living elephants.) Downey said that Hawaii’s ban in particular “tanked” the trade. Customers even in states where ivory remains legal are reluctant to purchase fossil ivory, he said.
“I understand why they’re doing it,” Downey told us. “I’d rather save all wildlife if there was a way.” But he said the effect of the bans on his business has forced him to prepare to exit the fossil ivory trade. He is selling his current ivory inventory at lower prices and not buying additional material.

Figure 2. A mammoth tusk carved with sea life by Lee Downey. Photo by Kevin Schumacher.

Figure 3. A selection from Artifactual’s inventory of fossil ivory. Clockwise from top left: belt buckle with mammoth ivory, knife with mammoth tooth handle, belt buckle with mammoth ivory, and frog carving of fossil walrus ivory. Photo by Kevin Schumacher.
Downey showed us a mammoth tusk carved with sea life (figure 2) as well as two belt buckles featuring mammoth ivory (figure 3). All of them use material sourced from Alaska. “This washes up on beaches and comes out of gold mines,” he said. “It’s highly sought after by the knife makers. It’s got colors that elephant ivories will never have. It just keeps weathering out of the dirt.” Downey added that this ivory is at least 10,000 years old.
Mammoth ivory can be differentiated from elephant ivory by a simple field test to observe its natural grain lines. But there is no test to determine whether a specimen of walrus ivory comes from a fossil or a modern animal. According to Downey, this is a problem in the trade.
Artifactual uses fossil walrus ivory from St. Lawrence Island, Alaska. This ivory is 500 to 15,000 years old and dug by the native Yupik people. “It’s part of their income, and they own the island,” he said. “For us it’s a legitimate and ethical trade.”
Downey added that the legislation on ivory also prohibits mammoth tooth because it comes from an ivory-bearing animal. He showed us a knife with a carved mammoth tooth handle (figure 3). Knife makers are some of the biggest buyers of mammoth tooth, he said, and the bans have dramatically impacted their business.

Figure 4. Left: “Alpha,” a stainless steel foundry-cast skull by Artifactual, one of six in a series. Right: “Gaia,” the second skull Downey carved from a piece of the Gibeon meteorite, has a tridymite crystal inclusion in the forehead. The geometric pattern on its surface was caused by the slow process of cooling as the meteor moved through space. Photos by Kevin Schumacher.
As a result of the decreased demand for ivory, Artifactual is moving its business to other materials, including jet, natural American turquoise and variscite, steel (figure 4, left), and meteorite. “Gaia” (figure 4, right) is carved from a piece of the Gibeon iron-nickel meteorite, which landed in prehistoric times in Namibia and is believed to be around four billion years old. The company also does a lot of business in silver.

Figure 5. A moose antler carving of a horned toad by Lee Downey. Photo by Duncan Pay.
Downey has also sought out materials similar to ivory but without the ethical and legal challenges. He has begun carving moose antlers naturally shed by the animals (figure 5). “The moose antler has been a really good substitute for the ivory,” he said. He also recently began carving vintage billiard balls. “We’ll carve anything that’s carvable,” he said.
Watch our video interview with Lee Downey.

	Interview with Lee Downey Source: GIA @topic:14


Title: Developments in Gemstone Analysis Techniques and Instrumentation During the 2000s Abstract: The first decade of the 2000s continued the trend of using more powerful analytical instruments to solve gem identification problems. Advances in gem treatment and synthesis technology, and the discovery of new gem sources, led to urgent needs in gem identification. These, in turn, led to the adaptation of newer scientific instruments to gemology. The past decade witnessed the widespread use of chemical microanalysis techniques such as LA-ICP-MS and LIBS, luminescence spectroscopy (particularly photoluminescence), real-time fluorescence and X-ray imaging, and portable spectrometers, as well as the introduction of nanoscale analysis. Innovations in laser mapping and computer modeling of diamond rough and faceted stone appearance changed the way gemstones are cut and the manner in which they are graded by gem laboratories.

	DATA DEPOSITORY

Additional References
	August 15, 2010 Source: GIA @topic:7


Title: Behind the Scenes of a Gemological Field Expedition Abstract: Field gemologists need to take preparation seriously if they are going to be ready to hike in jungle conditions. Andrew Lucas and Ahmadjan Abduriyim, of GIA in Japan, climb a trail covered with wet, slippery vegetation on marble pinnacles of rock to get to a ruby mining area of Vietnam. Photo by Vincent Pardieu/GIA

                      How do you mount a successful field expedition? Make sure you have the right people in place for the trip.

“Never go on a serious field expedition with people you don’t know. Make sure your team is ready and that they have the right attitude,” said Vincent Pardieu, senior manager for field gemology at GIA.

Gemology in the field is not the same as in a lab, he says. There are long stretches of communal living with nearly constant interaction with your traveling companions and reliance on local people to point you in the right direction.

Contrast that with a lab job where you get to go home every night and communicate with colleagues on your own terms, and you see that the challenges of fieldwork go well beyond gemological expertise.

“There is no way I will ask my boss to hire a person to work with me in the Field Gemology department based on a resume and few interviews,” Pardieu said. “To know if I can go on a serious expedition with a person, we need to spend time together in the field. Then I will be able to judge his skills and his attitude.”

Each member of the team needs to know precisely what he is expected to do, including how to interact efficiently with the other members of the team, Pardieu said. “Furthermore, a field expedition is about the gems, the place they are mined from and the people who mine them. The people are the key, because without their support you will not get where you want to go or get what you want to get.”

That is the context from which Pardieu, who is based in Bangkok, and Andrew Lucas, manager of field gemology for GIA Education in Carlsbad, broached the idea of traveling on a field expedition together when they met for dinner at a global GIA research meeting in late 2012.

Both gemologists have traveled extensively for their work: Pardieu to collect reference samples from gem mining areas to be used in laboratory work and Lucas to collect the details of the mine to market story for GIA’s education courses. Although their approach to gemology in the field is different, they soon found out they could learn from each other.

“During that evening we decided to try to combine our enthusiasm and our experience to build an efficient team that will benefit the lab and education,” said Pardieu, who asked Lucas to join his basic training program.

“Where do we start?” Lucas asked.

“Well, we already did,” Pardieu said. “It all starts with a good discussion around lunch or dinner. That’s the first time you get a sense of whether or not you have good rapport with each other.”

Trial Runs in Chanthaburi and Vietnam

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Pardieu suggested that Lucas travel to Bangkok for a weekend field expedition to Chanthaburi (Thailand) and Pailin (Cambodia) to visit ruby and sapphire mines so he could see first-hand how Pardieu and his team works in the field for the lab. Next would be a 10-day trip that included Vietnam.

“Vietnam is one of the most beautiful and challenging place I know,” Pardieu said. “The jungle-covered mountains of the Luc Yen district, where rubies and spinels are mined, is also home to a lively cutting and trading industry. But it is dangerous terrain. If you are not careful you might fall, be wounded or even die.”

Pardieu told Lucas to expect the unexpected and to physically prepare his 57-year-old body for the expedition.

“If you survive Vietnam, then we will be ready to travel on longer expeditions to places as challenging as Central Asia or Africa,” he said.

	Field gemology has significant risks. Pardieu, right, had a serious fall in a very treacherous and slippery ruby mine in Vietnam and suffered a significant fractured arm. This photo right after the accident shows his remarkable good spirit as he laughs with Lucas and still discusses the logistics of the trip. Photo by Clara Jennifer Haggai

Lucas did well on the May 2013 trip. Ironically, it was Pardieu, the younger man who warned everyone else about the rugged terrain of the mountains, who had an accident. He broke his left arm after losing his balance on some slippery marble pinnacles at the end of a long day of walking.

But what could have been a disaster turned out to be an interesting field experience for each member of the group, who banded together to immobilize Pardieu’s arm and carry him to help.

Ready to Explore Mogok
Pardieu and Lucas met again in November 2013, just after Pardieu had completed a successful scouting expedition in Mogok, Myanmar (formerly known as Burma), a legendary gem locale in an area known as Upper Burma. The region opened to foreign visitors in June 2013 after being closed for many years. Pardieu felt he had recovered well enough from his accident to go for some serious exploring there, including some underground adventures using ropes and wooden ladders.

Lucas has previously visited Myanmar several times, but had never been able to visit Mogok, and jumped at the opportunity to collect information about it for GIA Education. The time was right, the feeling between the two gemologists was good, so they decided to partner up for a field expedition to Mogok, Pardieu said.

The idea was to build a small, efficient team composed of a lab field gemologist to find ways to access the mines and collect reference samples; an education field gemologist to help take photos, work on a report and collect data for education; and finally, a videographer to document the whole adventure.

Although Mogok is accessible again, people are not free to go there. The Myanmar government requires travelers to get a permit to visit the gem-producing and trading area. A government-accredited guide must also travel with the group. Pardieu asked one of his friends, Jean Yves Branchard from Ananda travels in Yangon, to deal with the permits, guide and hotels.

He asked Jordan, one of his oldest friends in Mogok, to make arrangements to visit the mines. He met Jordan met in in 2000 when he studied gemology in Yangon and the two visited Mogok several times together until January 2005 when the Myanmar authorities stopped allowing foreigners in Mogok and the other gem-producing areas in Myanmar.

	“Traversing a rock wall in a ruby mine in Mogok that reaches a depth of 300 meters, gives you have a heightened sense of focus,” said Lucas, in red helmet. He found the activity much different from his desk work in Carlsbad. Photo by Vincent Pardieu/GIA
Pardieu, Lucas and their cameraman Didier Gruel focused on improving their stamina for the physically grueling trip. The challenge in Mogok is not about long hours walking in jungle or remote mountain areas, Pardieu said, it is in navigating the underground ruby mines that could be several hundreds of meters deep. Places like Kadoke Tad consist of an impressive network of wooden ladders that look like the underground Goblin kingdom in the movie “The Hobbit,” he said.

“Just take your time. Don’t try to move like the locals move: Each step, make sure you get a sure footing before you make the next step,” Lucas said after visiting these mines. “It’s better to be slow and sure than have a fast fall.”

The group visited numerous mines, markets and cutting areas practicing what Pardieu calls “‘doing gemology with your eyes and not your ears,” meaning getting the information yourself at the source, not secondhand from others. They also absorbed the culture and personality of the people and the beauty of their temples and pagodas.

“The time we spent together on previous field expedition was useful to improve our team’s efficiency,” Pardieu said. “Communication was easy and efficient. We were ready for the Mogok experience and everyone went home safely with great samples, thousands of photos, hours of video footage and wonderful memories.”

This is success by any definition of a great field expedition.

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Title: Spring 2020 G&G Available Now Abstract: After being delayed by the global pandemic, the Spring 2020 edition of Gems & Gemology is available now. This issue features two articles that quantitatively analyze the causes of color in corundum and blue to yellow beryl, respectively, with a focus on chromophores. It also offers an exciting look back at the evolution of jade carving craftsmanship in China, the rediscovery and early production of the Chivor emerald mine, an analysis of Swiss rhodonite, coverage of the Tuscon gem shows, and more.
A Quantitative Description of the Causes of Color in Corundum
The lead article, by Emily Dubinsky and co-authors, investigates the quantitative relationship between corundum’s color and chemistry. Using quantitative visible absorption spectroscopy and chemical analysis by SIMS, the authors are able to calculate the absorption cross section of six major chromophores that cause a wide array of color in corundum. Data is presented in the form of spectra and color circles.
The Evolution of Chinese Jade Carving Craftsmanship
China’s oldest and most important art form, jade carving, is steeped in history going back thousands of years. Mingying Wang and Guanghai Shi explore the evolution of jade carving tools and their impact on carving craftsmanship. With advancements in technology, jade carving has increased in complexity and delicacy while still reflecting Chinese philosophy and culture.
Color Characteristics of Blue to Yellow Beryl from Multiple Origins
Yang Hu and Ren Lu use quantitative spectroscopy and trace-element analytical techniques to study color characteristics and chromophores in blue to yellow beryl. This article also discusses the complex roles alkali ions and water have in beryl, though their influence on the blue to yellow color was found to be indirect.
History of the Chivor Emerald Mine, Part I (1880-1925): From Rediscovery to Early Production
Karl Schmetzer and co-authors dig deep into the history of the Chivor emerald mine in the first part of a two-part article. Their extensive research seeks to clarify historical inconsistencies, starting with the rediscovery of the site by Colombian mining engineer Francisco Restrepo, to mining title transfers and mining company formations, the impact of World War I, and the eventual bankruptcy of the Colombian Emerald Syndicate, Ltd.
Rhodonite-Pyroxmangite from Tanatz Alp, Switzerland
Swiss rhodonite is typically used to make cabochons, beads, and ornamental objects. Franca Caucia and co-authors analyze the chemical, physical, and gemological properties of this pale pink to purplish pink material. Rhodonite deposits can be found all over the world and have been widely investigated, but material from the Tanatz Alp is less well known.
Lab Notes
GIA laboratory staff members present their latest findings in the Lab Notes section, including the “Matryoshka” diamond from Siberia, corundum inclusions in diamond, an “electronic device” in an atypical bead cultured pearl, and the use of fluorescence spectroscopy for colored pearl treatment screening.
Micro-World
The Micro-World section, dedicated to the inner world of gemstones, features reversible twinning in neodymium pentaphosphate, a pallasitic peridot with iridescent needles, and sapphire with a phenomenon resembling play-of-color.
Diamonds from the Deep
Karen Smit and Steven Shirey examine the dissolution features that occur on diamond during storage in the mantle and transport to the earth’s surface. These unique surface features, influenced by the composition and temperature of the dissolving fluid/melt, help scientists better understand when diamond grows or dissolves.
Gem News International
Finally, GNI correspondents from around the world report on the Tucson 2020 gem shows, sapphires from Montana and Australia, sunstone from Ethiopia, and the new mineral dutrowite, named after well-known researcher, professor, and GIA governor Barbara Dutrow.
The Spring issue also contains the 2020 Gems & Gemology Challenge. Score 75% or better and you’ll receive a certificate of completion (PDF file); earn a perfect score and your name will be listed in the Fall 2020 issue. Online entries for the Challenge must be submitted by Friday, October 9, 2020. Source: GIA @topic:13


Title: Tucson 2020 Overview Abstract: Figure 1. A busy booth on the first day of the AGTA show. Photo by Tao Hsu.
In early February, despite the early phase of the COVID-19 outbreak, the Tucson shows were well attended and sales were brisk. Several vendors indicated that they had their biggest single day of sales ever this year (figure 1). This anecdotal evidence was supported by the strong demand for identification and origin services reported by the GIA Show Service Lab. This year, it was hard to identify any one particular item leading demand or any game-changing new gem material finds. Instead, we found that vendors were carrying high-quality material in terms of color, clarity, and cut. In fact, many were carrying items that had been meticulously carved, fantasy-cut, or recut for ideal proportions (figure 2).

Figure 2. A 72 ct gem silica carving by Nick Alexander showing a highly desirable intense shade of blue. The material is from the Ray mine in Arizona. Photo by Kevin Schumacher; courtesy of Nick Alexander.

Figure 3. A suite of the popular teal blue Montana sapphires from Rock Creek. The center stone is 11.03 ct, and the other 14 stones total 8.38 carats. Photo by Jennifer Stone-Sundberg; courtesy of Pala International.
Surpassing its strong momentum from the past few years, teal blue sapphire from Montana was a prominent and well sought-after item (figure 3). Sapphire was doing very well at the shows, including parti-colored, fancy-colored (electric colors such as fuchsia and pinks as well as pastels such as lavender), and slabs displaying zoning or trapiche-like patterning (figure 4).

Figure 4. Left: This set of 110 Australian sapphire “fancies” in 3 mm sizes was collected over several years. Right: A pair of trapiche-like Australian sapphire slices. Photos by Jennifer Stone-Sundberg; courtesy of Terry Coldham.

Figure 5. A 0.33 ct emerald from Malysheva, Russia, offered by Dudley Blauwet at the AGTA show. Photo by Kevin Schumacher.
Emerald from around the world could be found, including some untreated smaller sizes from Russia (figure 5), melee and small-sized finished stones from Pakistan, attractive material from Ethiopia, and an abundance of material in a wide variety of color, clarity, and size from Colombia, Brazil, and Zambia.
Outstanding brilliant green garnets in both demantoid and tsavorite varieties were available, including several larger-sized, ideally colored Russian demantoids (figure 6).

Figure 6. A 6.73 ct round brilliant Russian demantoid of top quality showing a horsetail inclusion. Photo © Christian Wild.

Figure 7. Deep blue aquamarine from Nasarawa, Nigeria (left to right: 1.94, 2.84, and 1.84 ct). Photo by Emily Lane; courtesy of Jeff Hapeman.
As “Classic Blue” is the Pantone color of the year and varieties of blue gemstones are very popular in general, gems prominently displaying a blue hue could be found throughout the shows. Along with sapphire, deep blue aquamarine from Nigeria (figure 7) was particularly popular, and many vendors displayed blue zircon, gem silica (again, see figure 2), apatite, cobalt spinel, blue topaz, haüyne, turquoise, blue moonstone, and lapis in their cases.
Electric-colored accent stones and melee in materials such as sapphire, spinel, apatite, and garnet varieties tsavorite and demantoid were easy to find both loose and in finished pieces (figure 8).

Figure 8. Sea star pendant by Paula Crevoshay featuring 4.04 carats of ruby, 5.06 carats of lavender sapphire, 9.40 carats of purple sapphire, 3.87 carats of fuchsia sapphire, 6.79 carats of crystal spinel, and 0.43 carats of amethyst, set in 18K yellow gold. Photo by Emily Lane; courtesy of Paula Crevoshay.

Figure 9. Parti-colored sapphire slices from Montana (left) and Australia (right). Photos by Jennifer Stone-Sundberg; courtesy of Warren Boyd (left) and Terry Coldham (right).
As has been the case for the past couple of years, gem slices in a variety of materials, shapes, and price points were very popular in both the AGTA and GJX shows. These are attractive to many designers, whether they are working with higher-price-point material such as parti-colored sapphire (figure 9), diamond, and trapiche emerald, or more moderately priced material including amethyst, rhodochrosite, and petrified wood.

Figure 10. Fluorescent hyalite opal flower pendant by Loretta Castoro, photographed in daylight-equivalent (left) and lower-power daylight-equivalent light with added short-wave UV light (right). The 12.63 ct fluorescent opal is from Zacatecas, Mexico. It is set in 18K yellow gold and has 48 yellow diamond accents (1.14 carats total) and 72 white diamond accents (1.27 carats total). Photos by Robert Weldon; courtesy of Loretta Castoro.

Figure 11. An extremely diverse selection of unusual stones was on display at the GJX show. Left: Bright green fluorite offered by a European vendor; photo by Tao Hsu. Right: Bicolor chrysoberyl carried by United Colour Stone Co. from Bangkok; photo by Jennifer Stone-Sundberg.
As always, Tucson was the place to find the unusual and phenomenal, with several vendors carrying exotic gem materials such as fluorescent hyalite opal (figure 10), star peridot, brilliant green fluorite (figure 11, left), hackmanite, triphylite, grandidierite, axinite, and an array of bicolor stones in materials such as garnet, chrysoberyl (figure 11, right), tanzanite, and sphene.

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An Inside Look at the 2020 Tucson Shows
2020 also marked the first Tucson edition of the Ethical Gem Fair. The exhibitors showed a wide range of gemstones, prices, and origins. They were all united in their commitment to responsible sourcing, traceability, transparency, and social awareness. The variety of exhibitors reflected the different approaches taken to address these diverse challenges around the world. During its inaugural Tucson show, the Ethical Gem Fair mainly attracted young independent jewelry designers looking for gems with a transparent chain of custody from the mine to their use in finished jewelry. Source: GIA @topic:7


Title: Bicolor Synthetic Sapphire Abstract: Figure 1. Split boules of bicolor synthetic sapphire grown by flame fusion. Photo by Jennifer Stone-Sundberg; courtesy of RusGems.
At the JOGS show, a wide selection of synthetic gem materials was offered by the Bangkok office of RusGems, a synthetic crystal growth company out of Russia. Olga Tanskaia showed us their extensive color range of synthetic sapphire, spinel, beryl, garnet, and other lab-grown crystals produced using a variety of crystal growth methods. She noted that blue and red synthetic gems are always their best sellers.

Figure 2. Left: Bicolor 14.83 ct synthetic sapphire showing popular teal blue and purple colors. Photo by Kevin Schumacher; courtesy of RusGems. Right: Wisps of presumably CoAl2O4 at the boundary of the teal and purple colors in the crystal. Photomicrograph by Nathan Renfro; field of view 7.05 mm.
As we found with natural sapphire this year, bicolor synthetic sapphire, both rough and cut, was also available and popular (figure 1). This material is grown by flame fusion, and the chromophore component of the powder composition is altered during the growth process at the desired length. Many different color combinations were available, including some with the popular teal blue and purple hues (figure 2, left). The inspiration for applying this method of color zoning to these flame-fusion grown crystals came from historical work on synthetic ruby laser rods where colorless (or “undoped”) regions were desired for the ends of the rods (figure 3). A process to grow a single crystal having pure aluminum oxide for a certain length, then adding the desired level of chromium to the growth for the laser rod portion of the length, and then returning to pure aluminum oxide was developed to achieve this.

Figure 3. Synthetic ruby rod grown by the flame-fusion technique showing chromium-free ends. Photo by Jennifer Stone-Sundberg; courtesy of RusGems.
We took the step-cut bicolor synthetic sapphire in figure 51 back to the GIA lab to determine the trace element chemistry responsible for generating the teal and purple hues. Using laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS), we found that the teal end contained no Be, Mg, Ti, V, Mn, Fe, or Ni but did contain small amounts of Cr and Ga (approximately 4 ppma and 0.5 ppma, respectively) and a substantial amount of Co (approximately 140 ppma). The purple end similarly contained no Be, Mg, V, Mn, Fe, or Ni but did contain small amounts of Ti (0.6 ppma) and Ga (0.4 ppma), with substantial amounts of Co (120 ppma), and Cr (470 ppma). Cobalt is giving this crystal the greenish blue component of its color, and chromium is modifying the hue to purple. We used UV-Vis spectroscopy to detect absorption peaks that could be used with the trace element chemistry to explain the two differently colored regions. We identified chromium peaks at approximately 400 and 560 nm responsible for the red color component in the purple half. We also identified an additional peak in the purple half at around 640 nm, likely due to Co3+. In the teal half, we did not find the Cr3+ peaks but did identify Co3+ peaks at 640 nm and at around 440 nm, and a peak around 600 nm due to Co2+ (K. Schmetzer and A. Peretti, “Characterization of a group of experimental Russian hydrothermal synthetic sapphires,” Journal of Gemmology, Vol. 27, No. 1, 2000, pp. 1–7).
In inspecting the inclusions at the boundary between the two differently colored portions, we discovered bright blue wisps of what we believe to be CoAl2O4 (figure 2, right), a spinel-structure material referred to as “cobalt blue” that is used to impart a blue color to glass, ceramics, and plastics.
The ability to generate just about any hue in sapphire, including color zoning, was readily apparent when looking through the offerings of RusGems. It was fascinating to see evidence of the direct influence of the high-tech laser industry on these synthetic gems. Source: GIA @topic:3


Title: New Blue Sapphire from Rakwana, Sri Lanka Abstract: A 49.99 ct rough sapphire crystal (5.8 cm in length) and a 33.16 ct cut stone with exceptional color from the 2019 Rakwana find. Photo by Robert Weldon/GIA.
The town of Rakwana, in southern Sri Lanka, has been known for decades as a premier source of royal blue sapphires. Often, a simple mention that a gemstone is from Rakwana will immediately explain the price and quality. In August 2019 a small pocket yielding numerous large sapphire crystals was discovered in the nearby Sinharaja Forest area of the Ratnapura District, Sabaragamuwa Province. What was unique about this find was the quality and size of the lustrous crystals. The 49.99 ct rough crystal in the figure above, measuring 5.8 cm in length and 1.6 cm at its widest point, was one of about 60 found in August 2019. It was also the largest complete crystal found. The beautiful 33.16 ct gem beside it was cut from a 207 ct piece of rough, the end of a large portion of a crystal. This crystal and cut gem rival the famous ones from Kataragama found four years ago. Source: GIA @topic:3


Title: Investigations into Corundum and Beryl Color, Jade Artistry, the Chivor Emerald Mine’s History, and Swiss Rhodonite… Abstract: Welcome to the Spring Gems & Gemology! Publication was significantly delayed by the COVID-19 pandemic, but we’re very proud to present this issue, which offers a blend of science, art, and history. In our lead article, authors Emily Dubinsky, Jennifer Stone-Sundberg, and John Emmett illuminate the chemistry behind gem corundum’s rich array of colors to reveal the influence of the concentrations of the six identified chromophores found in natural corundum on the depth of color. The authors use quantitative visible absorption spectroscopy and chemical analysis by secondary-ion mass spectrometry (SIMS) to study specially chosen synthetic and natural corundum samples to calculate each chromophore’s absorption cross section. This information is presented as spectra and color-circle arrays, which we hope practicing gemologists will find informative.
“This article provides insight for the practicing gemologist on the influence of six specific chromophores and their concentrations on depth of color in corundum.”
In our second paper, Mingying Wang and Guanghai Shi of the China University of Geosciences (Beijing) present a study of Chinese jade carving artistry ranging from time-honored, traditional techniques to state-of-the-art computer numerical control and 3D replicate engraving. Using data from almost 2,500 contemporary pieces, the authors demonstrate the art’s rich heritage and its continuing innovation.
Next, two more authors from the China University of Geosciences (Wuhan), Yang Hu and Ren Lu, examine the chromophores in blue and yellow beryl using quantitative spectroscopy and trace-element analysis to explore their color-causing characteristics. The authors show that different concentrations of iron ions with various valences and occupancies are most responsible for the gem’s blue to green to yellow colors.
Our following paper offers a change of topic. Karl Schmetzer, Gérard Martayan, and Jose Guillermo Ortiz provide the first of two installments detailing the checkered history of Colombia’s Chivor emerald mine: its abandonment, rediscovery, and intermittent operations by a fascinating cast of characters, including German gem merchant Fritz Klein.
In our final feature article, a team of Italian researchers led by Dr. Franca Caucia offers a study of the chemical, physical, and gemological properties of attractive rhodonite-rich rocks from Switzerland’s Tanatz Alp.
Our regular sections have much to offer, too. In Lab Notes, we describe diamonds with graphitic cavities and corundum inclusions, a clarity-enhanced glass imitating emerald, a large grandidierite, and curious pearls. Micro-World also provides intriguing curiosities, including a diamond with a mobile green diamond inclusion and a pallasitic peridot with iridescent needles. In Diamonds from the Deep, regular contributors Karen Smit and Steve Shirey demonstrate that diamonds are not necessarily forever with an exploration of the dissolution many diamond crystals suffer during transport in kimberlite magma. Our Gem News International section surveys gem materials and events from the 2020 Tucson gem shows, including star peridot, demantoid garnet, emerald, sapphire, trapiche gems, Tucson’s first ethical gem fair, and the results of the 2019 Buccellati jewelry design competition. Please also see the winners of our Dr. Edward J. Gübelin Most Valuable Article Award and this year’s G&G Challenge quiz.
Finally, do make sure you visit our new G&G Facebook group at www.facebook.com/groups/giagemsgemology. Since our February 2020 launch, over 7,000 of you have joined, so if you haven't seen it yet, please check it out. Thank you all for your support and interest! Source: GIA @topic:13


Title: Exceptional Rough and Cut Blue Sapphire from Rock Creek, Montana Abstract: The 17.65 ct “Lucky Sapphire” rough crystal and 3.92 ct oval cut using the custom “Helena” design, both from Rock Creek, Montana. Photo by Robert Weldon/GIA; courtesy of Jeffrey Hapeman.

The Rock Creek sapphire deposit in Montana has been active since the 1890s and is known as the state’s most fruitful deposit (T. Hsu et al., “Rock Creek Montana sapphires: A new age of mining begins,” https://www.gia.edu/
gia-news-research/rock-creek-montana-sapphires-new-age-mining-begins, August 29, 2016). This year in Tucson, Jeffrey Hapeman of Earth’s Treasury showed the authors a very fine untreated blue sapphire rough with a yellow spot in the center, as well as a top-quality faceted light teal blue untreated stone with some yellow zoning (see above). Since 2014, Mr. Hapeman has been focusing on Rock Creek material in these nontraditional lighter blues to greens. They have proven to be very popular, as several AGTA vendors this year reported strong demand for these colors, not only in Montana sapphire but from other sources as well. When it comes to unheated material, only about 5% of the rough from Rock Creek is cut without treatment, and most of these are either fancy pinks, yellows, or lighter blues. In the past year Mr. Hapeman has seen a shift in demand to parti-colored and green sapphires, particularly deep bluish green. Source: GIA @topic:1


Title: Alexandrite History and Lore Abstract: A 43-carat alexandrite in the collection of the British Museum.

                      Abundant alexandrite deposits were first discovered in 1830 in Russia’s Ural Mountains. Those first alexandrites were of very fine quality and displayed vivid hues and dramatic color change. The gem was named after the young Alexander II, heir apparent to the throne. It caught the country’s attention because its red and green colors mirrored the national military colors of imperial Russia.

	Alexander II was still a youngster in 1830, when a never-before-seen color-change gem
	was discovered in the Ural Mountains of Russia. - Corbis
The spectacular Ural Mountain deposits didn’t last forever, and now most alexandrite comes from Sri Lanka, East Africa, and Brazil. The newer deposits contain some fine-quality stones, but many display less-precise color change and muddier hues than the nineteenth-century Russian alexandrites. You’ll still find estate jewelry set with some of the famed Ural Mountain alexandrites. They remain the quality standard for this phenomenal gemstone. Source: GIA @topic:3


Title: Morganite Description Abstract: One of the advantages of beryl is its wide color range. These crystals show pastel shades: aquamarine's green and blue and morganite's pink. -photo credit Alan Jobbins.

                      Like many gems found in pegmatites, morganite can form large crystals. Miners in Brazil have found crystals as large as 22 lbs. (10 kg). The Smithsonian Institution in Washington, D.C., includes two faceted gems weighing 236 cts. and 250 cts. in its collection. Although morganite is rarer than aquamarine, large cut stones are readily available on today’s market. That’s probably because morganite hasn’t been promoted to the jewelry-buying public nearly as widely as aquamarine or emerald.

Most of the morganite on the market comes from pegmatite mines in Minas Gerais, Brazil. Afghanistan, Mozambique, Namibia, and the US have been minor and inconsistent sources. While it’s only a minor producer today, the original Madagascar deposit still sets the standard for the best material. That location’s yield of magenta-colored rough was superior to crystals from other sources.

This impressive morganite crystal from the Serra do Urucum mine, Galileia, Minas Gerais, Brazil, is 11 cm high. The faceted stone is 84.88 carats. - Jeff Scovil

This morganite mine is in the Brazilian State of Minas Gerais, near Govenador Valderas. Morganite is usually mined from solidified magma-released fluids called pegmatites. - Eric Welch/GIA. Source: GIA @topic:2


Title: Tourmaline History and Lore Abstract: This 376.85-carat tourmaline was carved by O. Hansen, using the colors of the tourmaline as part of the design. - Chip Clark, courtesy Smithsonian Institution, National Museum of Natural History

                      Somewhere in Brazil in the 1500s, a Spanish conquistador washed the dirt from a green tourmaline crystal and confused the vibrant gem with emerald. His confusion lived on until scientists recognized tourmaline as a distinct mineral species in the 1800s. The confusion about the stone’s identity is even reflected in its name, which comes from toramalli, which means “mixed gems” in Sinhalese (a language of Sri Lanka).  It’s a term Dutch merchants applied to the multicolored, water-worn pebbles that miners found in the gem gravels of Ceylon (now Sri Lanka).

It’s easy to understand why people so easily confuse tourmaline with other gems: Very few gems match tourmaline’s dazzling range of colors. From rich reds to pastel pinks and peach colors, intense emerald greens to vivid yellows and deep blues, the breadth of this gem’s color range is unrivalled. Brazilian discoveries in the 1980s and 1990s heightened tourmaline’s appeal by bringing intense new hues to the marketplace.

People have probably used tourmaline as a gem for centuries, but until the development of modern mineralogy, they identified it as some other stone (ruby, sapphire, emerald, and so forth) based on its coloring.

One of the earliest reports of tourmaline in California was in 1892. In the late 1800s, tourmaline became known as an American gem through the efforts of Tiffany gemologist George F. Kunz. He wrote about the tourmaline deposits of Maine and California, and praised the stones they produced.

In spite of its American roots, tourmaline’s biggest market at the time was in China.  Much of the pink and red tourmaline from San Diego County in California was shipped to China because the Chinese Dowager Empress Tz'u Hsi was especially fond of the color. There, craftsmen carved the tourmaline into snuff bottles and other pieces to be set in jewelry. San Diego County's famed tourmaline mines include the Tourmaline Queen, Tourmaline King, Stewart, Pala Chief, and Himalaya.

The miners became so dependent on Chinese trade that when the Chinese government collapsed in 1912, the US tourmaline trade also collapsed. The Himalaya mine stopped producing large volumes of gemstones. Other mines in San Diego County, like the Stewart Lithia mine at Pala, still produce sporadic supplies of gem-quality tourmaline.

	The Himalaya mine in Mesa Grande, California, produced this beautiful bicolor tourmaline
	crystal specimen. - Gift of William F. Larson

	The state of Maine has produced beautiful tourmalines. - Courtesy ICA/Courtesy of Boston Findings Co., Inc.

	A mine in California’s San Diego County produced this striking tourmaline. - Courtesy Bill and Jeanne Larson
The supply of tourmaline began to expand during the first half of the twentieth century, when Brazil yielded some large deposits. Then, beginning in the 1950s, additional finds appeared in countries around the world. Madagascar and Afghanistan have produced fine red tourmaline.

	Since the late 1980s, the Paraíba area of Brazil has been known as a source of strikingly intense tourmaline colors, called Paraíba tourmalines. Source: GIA @topic:1


Title: Citrine History and Lore Abstract: A brooch from the Victorian era features an oval citrine with six ruby accent stones. - GIA & Tino Hammid

                      People have used quartz in jewelry for thousands of years. Egyptians gathered ornately striped agates from the shore and used them as talismans, the ancient Greeks carved rock crystal ornaments that glistened like permafrost, and the hands of Roman pontiffs bore rings set with huge purple amethysts. Natural citrine is rare, and today most citrine quartz is the result of heat treatment of amethyst quartz. Even so, gems from the Victorian era have surfaced, and it’s not hard to imagine that citrine was treasured even in earlier times.

	This gold pendant from the Victorian era features a citrine center stone. - GIA & Tino Hammid

	This ornate Victorian citrine brooch is thought to be from the 1860s. - Robert Weldon, courtesy Linda Zorozek Source: GIA @topic:1


Title: Tourmaline Description Abstract: The intense green of this chrome tourmaline from Tanzania resembles the color of emerald.

                      Tourmalines come in a wide variety of exciting colors. In fact, tourmaline has one of the widest color ranges of any gem species, occurring in various shades of virtually every hue.

Many tourmaline color varieties have inspired their own trade names:

		Rubellite is a name for pink, red, purplish red, orangy red, or brownish red tourmaline, although some in the trade argue that the term shouldn’t apply to pink tourmaline.

		Indicolite is dark violetish blue, blue, or greenish blue tourmaline.

		Paraíba is an intense violetish blue, greenish blue, or blue tourmaline from the state of Paraíba, Brazil.

		Chrome tourmaline is intense green. In spite of its name, it’s colored mostly by vanadium, the same element that colors many Brazilian and African emeralds.

		Parti-colored tourmaline displays more than one color. One of the most common combinations is green and pink, but many others are possible.

		Watermelon tourmaline is pink in the center and green around the outside. Crystals of this material are typically cut in slices to display this special arrangement.

	The colors displayed by the crystal and fashioned gem are typical of tourmaline with the trade name of rubellite. - Courtesy William F. Larson, Pala International

	Copper is the element that contributes to this Paraíba tourmaline’s highly prized color.

	This attractive slightly brownish, orangy yellow tourmaline is from the Merelani area of Tanzania.

	Some tourmaline crystals display different color zones within a single crystal. - Jeff Scovil
Some tourmalines also show a cat’s-eye effect called chatoyancy. Cat’s-eye tourmalines are most often green, blue, or pink, with an eye that’s softer and more diffused than the eye in fine cat’s-eye chrysoberyl. This is because, in tourmaline, the effect is caused by numerous thin, tube-like inclusions that form naturally during the gem’s growth. The inclusions are larger than the inclusions in cat’s-eye chrysoberyl, so the chatoyancy isn’t as sharp. Like other cat’s-eyes, these stones have to be cut as cabochons to bring out the effect.

A tourmaline’s chemical composition directly influences its physical properties and is responsible for its color. Tourmalines make up a group of closely related mineral species that share the same crystal structure but have different chemical and physical properties. They share the elements silicon, aluminum, and boron, but contain a complex mixture of other elements such as sodium, lithium, calcium, magnesium, manganese, iron, chromium, vanadium, fluorine, and sometimes copper.

Gemologists use a tourmaline’s properties and chemical composition to define its species. The major tourmaline species are elbaite, liddicoatite, dravite, uvite, and schorl.

Most gem tourmalines are elbaites, which are rich in sodium, lithium, aluminum, and sometimes—but very rarely—copper. They occur in granite-containing pegmatites, which are rare igneous rocks. Pegmatites are sometimes rich in exotic elements that are important for the formation of certain gem minerals.  Pegmatites might contain very large crystals up to 1 meter (about 3 feet) in length. Because of the nature of pegmatites, different gem pockets within one pegmatite body can hold tourmaline crystals of very different colors. Or one pocket can produce a variety of differently colored tourmalines. As a result, many mines produce a variety of gem colors.

Another feature of gem pegmatites is the scattered distribution of pockets within them. For miners, working a pegmatite consists mostly of excavating barren rock until the work results in the occasional and sudden reward of a rich pocket full of spectacular gem crystals.

Elbaites offer the widest range of gem-quality tourmaline colors. They can be green, blue, or yellow, pink to red, colorless, or zoned with a combination of colors.

Liddicoatite is rich in calcium, lithium, and aluminum. It also originates in granite-containing pegmatites and offers a diverse array of colors, often in complex internal zoned patterns. It’s named after the late Richard T. Liddicoat, former president of GIA and former chairman of its Board of Governors. He’s often referred to as the “Father of Modern Gemology.”

Uvite is rich in calcium, magnesium, and aluminum. Dravite is rich in sodium, magnesium, and aluminum. Both form in limestone that’s been altered by heat and pressure, resulting in marble that contains accessory minerals like tourmaline.

Some of the most important gem tourmalines are mixtures of dravite and uvite. They’re often brown, yellowish brown, reddish brown, or nearly black in color, but sometimes they contain traces of vanadium, chromium, or both. When present in the right concentrations, these impurities produce rich green hues that rival those of tsavorite garnet and, occasionally, even emerald. Dealers sell these gems as chrome tourmaline, even though they’re not always colored by chromium.

The bright yellow gems some dealers call “savannah” tourmalines are also mixtures of dravite and uvite. Their coloring element is iron.

Schorl is typically black, and rich in iron. It forms in a wide variety of rock types. It’s rarely used as a gem, although it has been featured in mourning jewelry.

Tourmaline’s colors have many different causes. It’s generally agreed that traces of iron, and possibly titanium, induce green and blue colors. Manganese produces reds and pinks, and possibly yellows. Some pink and yellow elbaites might owe their hues to color centers caused by radiation, which can be natural or laboratory-induced. Source: GIA @topic:12


Title: Topaz Journey Abstract: Few people outside the gem industry realize the true nature of a gemstone’s journey from the mine to the counter of a store. Whether the gem is being offered to consumer’s at a traditional jewelry store’s counter, an internet shopping site, or a television broadcast the journey always involves a great deal of effort.  Tons of earth and countless hours of labor are needed to being a gem from mine to market. Source: GIA @topic:7


Title: Rose Quartz Description Abstract: The soothing soft pink shades of rose quartz appeal to gem carvers and collectors. – Valerie Power, courtesy Arunashi

                      People accept a certain amount of sand, dirt, and dust as ordinary ingredients in their lives. What they might not be aware of is that those substances are mostly quartz, one of the most common minerals on earth.

	There are many attractive and well-known quartz varieties. The oval gem—fourth from the right—is rose quartz, one of the less abundant gems in the quartz family. – Robert Weldon
Rose quartz is one of the many quartz varieties used as a gem material. It gets its name from its delicate pink color, which ranges from very light (almost white) to medium-dark. The most appealing color typically occurs in larger sizes, and small rose quartz specimens with good color tend to be rare. Rose quartz is always found in massive form, so it lacks regular, flat crystal faces. It’s typically found in pegmatites, but also occurs in hydrothermal veins.

Research has shown that rose quartz owes its delicate pink color to microscopic inclusions of aligned silicate mineral fibers. Advanced testing has shown that they’re generally similar—but not identical—to the mineral dumortierite. The fibers likely crystallized out as the host gem cooled, and they’re aligned according to the crystal directions of the rose quartz.

	Rose quartz contains mineral inclusions that give it a soft pink color. This ring was carved from a single piece of rose quartz. - Eric Welch, courtesy Jana Miyahira-Smith

	Rose quartz beads, cabochons, and rough make an enticing arrangement in a store’s display case. – Robert Weldon
This pastel gem’s inclusions give it a characteristic cloudy translucence, so it’s generally cut into beads and cabochons. Sometimes, the inclusions produce a six-rayed star if the fashioned gem is cabochon-cut and correctly oriented. Fine examples show a distinct, sharp, star floating above even pink bodycolor. The most transparent rose quartz rough might be faceted. Cutters can intensify the delicate color by applying concave facets and cutting gems in larger sizes.

	This star rose quartz is considered fine quality because of its depth of color, degree of transparency, and sharply defined star. – Robert Weldon
The delicate translucence of rose quartz inspires gem carvers to create dainty or whimsical figures. The finest-quality rose quartz rough typically comes from Brazil. Other sources include India, Madagascar, and Sri Lanka.

	This adorable piglet was carved by Gerd Dreher from rose quartz mined in Madagascar. – Robert Weldon
Besides the typical cloudy rose quartz, which is colored by inclusions, there’s a type of transparent quartz that owes its pink color to a different mechanism. Some in the trade call it “pink crystalline quartz,” “crystalline rose quartz,” or simply “pink quartz.” Compared to massive rose quartz, it’s exceptionally rare. It might occur as beautiful clusters of transparent, well-formed crystals. The finest examples are from Brazil, especially a deposit near Galiléia, located near Governador Valadares in the state of Minas Gerais. The best are often left as mineral specimens, which can command high prices at auction. In 2013, a superb example called La Madona Rosa (the Pink Madonna) sold for $662,500. This specimen measures 15.5 x 8 inches (39 x 20 cm) and features a core of smoky quartz that resembles a human form surrounded by a glittering halo of transparent pink quartz crystals.

Material from some of these deposits will fade when exposed to natural light, but its color can be restored by irradiation. Research by Russian crystal growers on synthetic pink quartz has demonstrated a color-causing mechanism, which can cause results very similar to the natural material. Growers produce pink color in transparent synthetic quartz by growing it with impurities of aluminum and phosphorous. Some of these impurities replace silicon in the quartz lattice. Subsequent irradiation produces color centers that give the crystal its pink color. Source: GIA @topic:1


Title: Peridot History and Lore Abstract: This 146.10-carat peridot is in the collection of the Natural History Museum in London

                      Peridot has always been associated with light. In fact, the Egyptians called it the “gem of the sun.” Some believed that it protected its owner from “terrors of the night,” especially when it was set in gold. Others strung the gems on donkey hair and tied them around their left arms to ward off evil spirits.

The word peridot comes from the Arabic “faridat,” which means “gem.” Most peridot formed deep inside the earth and was delivered to the surface by volcanoes. Some also came to earth in meteorites, but this extraterrestrial peridot is extremely rare, and not likely to be seen in a retail jewelry store.

Early records indicate that the ancient Egyptians mined a beautiful green gem on an island in the Red Sea called Topazios, now known as St. John’s Island or Zabargad. Legend has it that the island was infested with snakes, making mining unpleasant until an enterprising pharaoh drove them into the sea. From the earliest times, people confused this stone—now known to be peridot—with other gems. It was one of many labeled as “topaz.”

Some historians believe that Cleopatra’s famous emerald collection might actually have been peridot. People in medieval times continued to confuse peridot with emerald. For centuries, people believed the fabulous 200-ct. gems adorning the shrine of the Three Holy Kings in Germany’s Cologne Cathedral were emeralds. They are, in fact, peridots. Source: GIA @topic:1


Title: Peridot Description Abstract: While the 64.57-carat cut peridot is magnificent, it is overshadowed by the amazing 7.9-cm tall crystal. Both are from Sappat, Kohistan, Pakistan. - Jeffrey Scovil

                      Gem miners find peridot as irregular nodules (rounded rocks with peridot crystals inside) in some lava flows in the United States, China, and Vietnam and, very rarely, as large crystals lining veins or pockets in certain types of solidified molten rock. Sources for the latter include Finland, Pakistan, Myanmar, and the island of Zabargad.

	This incredible suite of peridot jewelry has a total weight of 350.40 carats. All are top-quality peridots from Pakistan. - © GIA & Harold & Erica Van Pelt
Geologists believe both types of deposits relate to the spreading of the sea floor that occurs when the earth’s crust splits, and rocks from its mantle are pushed up to the surface. Sometimes—as in Myanmar— these rocks can be altered, deformed, and incorporated into mountain ranges by later earth movements.

Rarely, peridot can have an extraterrestrial source, being contained in meteorites that have fallen to earth.

The color range for peridot is narrow, from a brown-green color to yellowish green to pure green. Yellowish green is the most common peridot color seen in jewelry.

	Peridot is best known for its yellowish green color.
Peridot is the gem variety of the mineral olivine. Its chemical composition includes iron and magnesium, and iron is the cause of its attractive yellowish green colors. The gem often occurs in volcanic rocks called basalts, which are rich in these two elements.

	These peridots from Peridot Mesa in the San Carlos Apache Nation, Arizona, are set in a jewelry style called "Healing Sisters.” - Courtesy Apache Gems Source: GIA @topic:1


Title: Lapis Lazuli Description Abstract: Lapis lazuli is an aggregate of several minerals. Lazurite grains provide its characteristic blue color, while golden flakes of pyrite can add attractive contrast.

                      Lapis lazuli is a rock, which means it’s an aggregate of several minerals. This ancient gem contains three minerals in varying amounts: lazurite, calcite, and pyrite. Sometimes, it also contains one or more of the following: diopside, amphibole, feldspar, and mica.

	Lapis lazuli is an aggregate of several minerals. Lazurite grains provide its characteristic color. The higher the percentage of lazurite grains in the aggregate, the darker the blue color. - John Koivula
Lapis frequently contains varying amounts of whitish calcite matrix—the host rock that surrounds the gem—or flecks or veins of glinting yellow pyrite, or both. The gem can also have a smoothly uniform bodycolor, free of visible pyrite and calcite.

	Calcite shows up as white flecks or streaks in the aggregate.

	The golden, metallic-looking spots in lapis are pyrite. - Robert Weldon, courtesy Gary Bowersox
Lapis is semitranslucent to opaque, with a waxy to vitreous luster. It has fair toughness, and its hardness ranges from 5 to 6 on the Mohs scale, depending on the mix of minerals.

Variously described as indigo, royal, midnight, or marine blue, lapis lazuli’s signature hue is slightly greenish blue to violetish blue, medium to dark in tone, and highly saturated. In its most-prized form, lapis lazuli has no visible calcite, although it might have gold-colored pyrite flecks. If the flecks are small and sprinkled attractively throughout the gem, their presence doesn’t necessarily lower lapis lazuli’s value. The lowest-quality lapis looks dull and green, the result of an excess of pyrite. Lapis with white calcite streaks is less valuable.

	The calcite matrix in this cabochon will lower its appeal to most buyers. - Robert Weldon
Although many people associate lapis with dark blue, it’s also found in other shades of blue, and even other hues. Its color can range from deep violet blue and royal blue to light blue to turquoise blue to a greenish blue. The combination of different minerals in the aggregate determines the color. For example, lazurite is responsible for producing royal blue lapis, while a mineral called afghanite creates a pale blue shade.

	This striking freeform carving displays a lovely shade of blue along with attractive golden pyrite accents. - Robert Weldon, courtesy Gary Bowersox
Worldwide, lapis is mined in several areas. The traditional source of the finest lapis lazuli is the same today as it was thousands of years ago—the mountains of Afghanistan. Other major sources are Chile and Lake Baikal in Siberia, Russia. Minor sources are Angola, Canada, Colorado (US), and Pakistan.

	Afghanistan is the world’s major source of lapis lazuli as well as the major source of the gem’s best color. - Dr. Edward J. Gubelin Source: GIA @topic:1


Title: Ametrine History and Lore Abstract: Concave facets on the pavilion contribute to the striking look of this 27.50-ct. ametrine. Creative gem cutters sometimes use concave facets to give a gem a dramatic appearance. Photo by Robert Weldon/GIA, courtesy Minerales y Metales del Oriente.

                      The world’s only commercial source of ametrine is the Anahi mine in southeastern Bolivia. Legend has it that a Spanish conquistador discovered the mine’s location in the 1600s and introduced the gem to Europeans when he presented several specimens to his queen. The mine had been given to him as a dowry when he married a native princess named Anahi. After that, the mine was lost for more than three centuries. Rediscovered in the 1960s, the mine’s ametrine began appearing on the market again during the 1970s. Today the mine, named Anahi for the legendary princess, also produces natural amethyst and citrine.

	The mine, located near the center of the photo, is barely visible through the foliage between the two mountains. Photo by Robert Weldon/GIA.
The mine area is remote. Travel to and from the mine is limited to a flight in a small airplane or by a combination of roads and boats. Some supplies and personnel travel to and from the mine by air. Supplies and mine production move by boat. It’s not hard to imagine why the mine’s location was lost for centuries.

	A clearing near the mine has space for only a small airplane. Photo by Robert Weldon/GIA.

	A miner pushes a cart full of waste material in the depths of Bolivia’s Anahi ametrine mine. Photo by Robert Weldon/GIA. Source: GIA @topic:1


Title: Ametrine Description Abstract: This amazing ametrine trilliant cut features a multitude of facets to create internal reflections that blend the amethyst and citrine colors. Photo by Robert Weldon/GIA, courtesy Minerales y Metales del Oriente, Bolivia, SA.

                      Transparent, bicolored quartz with the colors of both amethyst and citrine in the same gem is called ametrine or amethyst-citrine. The contrasting colors give it an intriguing appearance.

Fine ametrine shows medium dark to moderately strong orange, and vivid to strong purple or violetish purple. Larger gems, usually those over 5 carats, tend to show the most intensely saturated hues. Dealers look for an attractive half-and-half distribution of each color, with a sharp boundary between the two colors at the center of the fashioned gemstone.

Ametrine is often cut as a rectangular step cut because that style nicely displays the bicolor effect. Cutters try to emphasize both colors equally.

	Rectangular step cuts clearly show off the striking bicolor nature of these ametrines. Photo by Maha Tannous/GIA.
Cutters  sometimes fashion ametrines as mixed cuts or brilliant cuts and use internal reflections to mingle the amethyst and citrine colors. Ametrine is also popular in free-form or fantasy cuts.

Ametrine is a form of quartz in which the colors of the amethyst and citrine quartz varieties are present in the same crystal. Photo by Robert Weldon/GIA, courtesy Minerales y Metales del Oriente, Bolivia, SA.

	A unique display of ametrine’s colors blends and contrasts in this fantasy cut by noted gem designer John Dyer. He named his creation Ametrine SunRay ™. Photo by Lydia Dyer, © John Dyer & Co., gem courtesy John Dyer & Co.
There’s only one commercial source of natural ametrine: a deposit in eastern Bolivia, close to the Brazilian border. Legend has it that a Spanish conquistador discovered the location in the 1600s, but it was lost for more than three centuries. Ametrine began appearing on the market again during the 1970s. The mine, the Anahi, also produces natural amethyst and citrine.

	The Anahi mine in eastern Bolivia is the source of these rough ametrine crystals. Photo by Robert Weldon/GIA, courtesy Bart Curren. Source: GIA @topic:2


Title: Amethyst Description Abstract: This amethyst crystal is from Namibia. It shows classic quartz crystal shape: a six-sided columnar crystal with a pyramid-shaped termination at the top. Courtesy Daniel Trinchillo, Fine Minerals International.

                      Amethyst is the purple variety of the quartz mineral species. It’s the gem that’s most commonly associated with the color purple, even though there are other purple gems such as sapphire and tanzanite. Its purple color can be cool and bluish, or a reddish purple that’s sometimes referred to as “raspberry.”

	Most people think of amethyst when they picture a beautiful purple gem. Courtesy Intimate Gems.
Amethyst’s purple color can range from a light lilac to a deep, intense royal purple, and from brownish to vivid. Amethyst also commonly shows what is called color zoning, which in the case of amethyst usually consists of angular zones of darker to lighter color.

	Amethyst commonly shows zones of darker and lighter colors. Photo by Mike Havstad/GIA. Source: GIA @topic:2


Title: Tucson 2019 Overview Abstract: Buyers browse the selection of goods available at the 2019 AGTA GemFair in Tucson. Photo courtesy of AGTA.
The 2019 gem shows came to Tucson with a wealth of material, both new and old, as eager buyers descended on exhibitors to take in the latest trends. While traffic was not as heavy as in recent years, several vendors noticed an influx of young people looking for natural, untreated gemstones. Spectacular color in gems and stunning jewelry designs were on view, while many pointed to sustainable and ethical practices as a major consideration in their colored gemstone and jewelry purchases.

	Overview of gemstone supply and demand

The Asian market has slowed, according to Edward Boehm of RareSource (Chattanooga, Tennessee), and as a result, gems that have been popular in Asia, particularly China, are starting to gain traction in the United States. Boehm indicated that the growth of the Asian market is still driving production in African countries, particularly Nigeria, and Americans are the primary consumer of this increased production. Improving exchange rates have also worked in the American market’s favor. Dave Bindra (B&B Fine Gems, Los Angeles) said that while higher-end gemstones are still difficult to come by, they are as much in demand as ever. Commercial-grade gems, Bindra noted, have become more accessible. Like Boehm, he attributes this in large part to activity in the Chinese market in recent years. Shahin Aboosalih of SR Trading’s Hong Kong office talked to us about material that remains popular in the Chinese and Japanese markets.

Left: Opals like “The Chief,” a 14.41 ct Australian black specimen, were in demand this year. Photo by Kevin Schumacher, courtesy of 100% Natural Ltd. Center: Fancy-color sapphires, including this 50.08 ct color-change gem, were also popular. Photo by Robert Weldon/GIA, courtesy of Edward Boehm. Right: The secondary market is an excellent source for material, such as this 115.13 ct golden sapphire. Photo by Kevin Schumacher, courtesy of B&B Fine Gems.
Opal, particularly black opal, has seen a resurgence among high-end jewelers. Boehm believes there could be a growing appreciation for the gem due to the discovery of opal in Ethiopia, which has brought opal to different price points and different audiences in the past decade. Rod Griffin (Rod Griffin Boulder Opals) discussed his experiences in Australian opal mining and the new technology he is using to exploit deposits once thought to be depleted.
Color, of course, continues to reign, and dealers are seeing what Boehm called “an increased appreciation for the unusual.” Beyond the classic “Big Three,” vendors stocked gemstones such as sphene, grandidierite, and various colors of sapphire. Color-change stones seen in previous shows, such as pyrope garnet and alexandrites, were also on display and drawing new attention. Cutters, he noted, are making strides in recognizing and using to different effect specific phenomena in gemstones, such as the trichroism of tanzanite. Spinel remains the most popular “new” gem, according to Boehm, especially in nontraditional colors such as lavender and violet, which would have been cut too dark (or not at all) in the past. Gray spinel in particular made a splash at this year’s show, with several exhibitors stocking the material in a variety of cuts.
Brian Cook of Nature’s Geometry (Tucson) noticed a cross-pollination between the mineral and jewelry industries, with more designers and jewelers using raw euhedral stones to create unique looks. He also noted that several new mineral shows, developed out of dealers’ collectives rather than sponsored by one promoter, have come to the city and seem to be here to stay. The popularity of the Granada Gallery, which prides itself on its dedication to “fine natural design,” is one such indicator.
American gemstones were also in heavy rotation at the shows. Eric Braunwart of Columbia Gem House, who has long stocked American production in his inventory, said that sales of these products were good. Designer Derek Katzenbach discussed his use of American gemstones such as Maine tourmaline. And among the material seen was Montana sapphire, nephrite from Washington State, Oregon sunstone, and hyalite opals from Oregon.
Bindra noted that many of his company’s rare gems came out of the ground 20–30 years ago, and that he relies heavily on the secondary market to procure such material. In this way, he is able to provide his clients with the high-end material they have come to expect. This sentiment was echoed by Jared Holstein of Perpetuum Jewels, a wholesaler working with antique diamonds and colored stones in historical cuts for the bridal market. Holstein also finds the secondary market to be a good way to source gemstones in an ethical and environmentally sustainable fashion.
Responsibly sourced material continues to be heavily sought after. Braunwart said this might have been his most successful show in his 41 years at Tucson. He credits this in large part to his commitment to providing fair trade, responsibly sourced gemstones. Susi Smither, who founded The Rock Hound specifically to create an ethical jewelry line, delighted in showing us her Molten Muzo collection, which used responsibly sourced Colombian emeralds and recycled gold. And gem dealer and jewelry designer Roger Dery told us about Gem Legacy, the nonprofit he founded to benefit East African mining communities.
We hope you enjoy our coverage of the 2019 Tucson gem shows!
The following contributed to this report: Erin Hogarth, Tao Hsu, Jonathan Muyal, Lisa Neely, Aaron Palke, Duncan Pay, Albert Salvato, Kevin Schumacher, Jennifer Stone-Sundberg, Wim Vertriest, and Robert Weldon.

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An Inside Look at the 2019 Tucson Shows Source: GIA @topic:7


Title: Winter 2019 G&G: Geographic Origin Special Issue Abstract: The Winter 2019 edition of Gems & Gemology is devoted to the determination of geographic origin for specific colored gemstones. This issue hopes to promote a healthy discussion about this complex subject, and bring greater transparency on the testing methods and criteria utilized in GIA’s laboratories.
The Geographic Origin Dilemma
Shane McClure and co-authors introduce the many facets of geographic origin determination. The authors explain that in order to adequately issue geographic origin reports, a laboratory must meet three requirements: scientific instrumentation, experienced gemologists, and a comprehensive collection of reference samples of known provenance.
Geology of Corundum and Emerald Gem Deposits: A Review
Similar geologic environments can produce gems with similar gemological properties, making it difficult to connect the properties of individual gems to the geology of their deposits. Gaston Giuliani and Lee Groat review the classification systems of corundum and emerald deposits, and discuss how genetic models can give geologic and geographic clues on their origins.
Field Gemology: Building a Research Collection and Understanding the Development of Gem Deposits
Wim Vertriest, Aaron Palke, and Nathan Renfro discuss the importance of building a reliable reference collection of known provenance in order to support geographic origin determination. Since gem-producing areas are constantly changing, field gemologists play a critical role in documenting the global mining and trading environment and the development of gemstone enhancement procedures.
A Review of Analytical Methods Used in Geographic Origin Determination of Gemstones
Origin determination is possible because there is a close relationship between the geology of an area and the properties of gemstones found there. Groat and co-authors take an in-depth look at the analytical techniques commonly used to characterize gemstones.
Geographic Origin of Specific Gemstones
In some cases, the value of a gemstone depends strongly on its geographic origin. Careful analysis of inclusions, trace element chemistry, and spectroscopic data often lead to conclusive origin determination. However, there are instances where the overlap in data is too great and laboratories are unable to make the call. Each article in this series—blue sapphire, ruby, emerald, Paraíba tourmaline, and alexandrite—outlines GIA’s methods and criteria for establishing geographic origin of that particular gemstone.
What’s Next?
What does the future hold for the geographic origin service? Could non-industry instrumentation and techniques be adapted to gemstone applications in order to improve consistency? McClure and co-authors explore whether developing a service for additional gemstones carries enough value to justify the expense. Source: GIA @topic:1


Title: Varieties of Rutilated Quartz – Tucson 2014 Abstract: Figure 1. This 85 ct quartz crystal contains bright reddish rutile needles. Photo by Robert Weldon; courtesy of Rare Earth Mining Co.

              Rutilated quartz has come into its own as a mainstream gem material, thanks in part to its seemingly infinite variety and one-of-a-kind appeal for jewelry designers. Reddish rutile, owing its color to traces of iron, was exhibited at the AGTA show by Rare Earth Mining Co. (Trumbull, Connecticut). Rare Earth CEO Bill Heher said the material was recovered from Bahia in northern Brazil some decades ago before the mine closed. But due to the rising value of rutilated quartz, the deposit has been reopened and worked in recent years. The distinctiveness of the material, in this case an 85 ct gem (figure 1), lies in its relative transparency and bright reddish color—which can be matched or contrasted in jewelry.

Golden and copper-color rutile is traditionally seen in quartz, and connoisseurs are always on the lookout for a six-rayed star pattern of rutile. Though such stars occur regularly in the rock crystal, they are rarely oriented in such a way to be easily cut into a faceted or cabochon gem. Strong, isolated rutile stars located in the rough must be painstakingly oriented to be visible face-forward, as in the 34.55 ct gem (figure 2) cut by Falk Burger (Hard Works, Tucson). At the center of the star, an additional inclusion of hematite is visible.

	Figure 2. This 34.55 ct quartz has been cut to display the star-shaped needle formation. Photo by Robert Weldon; courtesy of Hard Works.

	Figure 3. This 209.06 ct quartz features a rose-shaped cluster of inclusions. Photo by Robert Weldon; courtesy of Hard Works.
Burger said that rutile can take unusual forms as well. Minute gray rutile needles in the top of the quartz in figure 3 are clustered in the shape of a rose. The quartz also contains layers of pink and greenish chlorite phantoms. The quartz itself weighs 209.06 ct, and was fashioned by Burger to best exhibit the rutile rose. Source: GIA @topic:3


Title: Update on Colored Gemstone Mining in Tanzania Abstract: Figure 1. A view of the pink sapphire mining pit at Kibuko, in the Uluguru Mountains of Tanzania. Photo by Vincent Pardieu/GIA.

	A team of GIA field gemologists visited Tanzanian mines in the summer of 2016 to collect ruby and sapphire for GIA’s reference collection and explore new sources of colored stones. The field expedition, led by these authors, visited many known Tanzanian gem localities as well as new deposits at Loolera, Kibuko (figure 1), Lutela, Amani Makoro, and Ngapa. The trip was made possible by the support of Mark Saul of Swala Gem Traders (Arusha, Tanzania), Tanzanian gem broker Justin Mmbaga, and several regional mining officers. We found that the most active colored gemstone mining area is still Merelani, which produces tanzanite and green grossular garnet. Ruby and sapphire output has been relatively low since the 2009 discovery of the ruby deposit in Montepuez, Mozambique, as confirmed by our Tanzanian sources.

	Tanzanian miners supply stones to licensed brokers, who are allowed to buy and transport gems within the country. These brokers sell to licensed master dealers, who are allowed to export internationally. These master dealers are mainly located in Dar es Salaam and Arusha. While we met Thai and Sri Lankan buyers in Mahenge, Songea, and Tunduru, foreigners must have approval from regional mining officers and possess a proper business visa to visit the deposits. This is particularly enforced in southern Tanzania; around Songea, we met immigration officers who were “hunting for foreigners.”

	Our journey started in Longido, where rubies were discovered about 100 years ago (D. Dirlam et al., “Gem wealth of Tanzania,” Summer 1992 G&G, pp. 80−102). The main operation in the Longido area is the Mundarara ruby mine, currently Tanzania’s largest, with a workforce of 78 people. The gems are extracted from an underground tunnel about 200 meters deep crossed by several horizontal tunnels that host most of the production. The mine yields ruby in zoisite (suitable for carving), as well as some cabochon- and facet-grade material of a very deep red color. The color is reminiscent of rubies from Mozambique.

	We continued to the Umba River, where Tanzanian sapphire production began after World War II and a ruby-bearing area was discovered by Georges “Papas” Papaeliopoulos in the 1950s (again, see Dirlam et al., 1992). The situation has changed significantly since author VP visited in 2005 and 2009. At the time there was a dispute between the company working the deposit, called “Amazon,” and local communities. The dispute ended with the government revoking Amazon’s license. During our 2016 expedition, we witnessed about 40 small-scale local miners using hand tools to work the primary deposit discovered by Papaeliopoulos, as well as secondary deposits scattered along the banks of the Umba. Most of the production is traded each evening around the Mississippi Hotel in Umba.

	In the Kilindi area, about halfway between Umba and Winza, a new ruby deposit has been discovered near the Maasai village of Loolera. This site, located atop a hill, produces gems very similar to those found near Winza in 2007. We visited the area with the support of the village leader, who said the first rubies were found about 10 years ago, but the quality of the stones was low. A few miners were working the deposit sporadically using hand tools. But in April 2016, some good-quality material was found in amphibole matrix, attracting considerable interest. About 25 mining licenses were issued during the summer of 2016, but there is a sense that the area is under the control of a few major players.

	The deposit where the first rubies at Loolera were found is owned by a miner called Dr. Ozu. The mining pit appeared to be about 90 meters deep, but we could not inspect the tunnel as Dr. Ozu was not present. We studied the entrance and looked through the tailings near the pit. In these rejects we found many small fragments of rubies associated with garnets, amphibole, mica, and feldspar. Although the material we saw resembled Winza ruby, the stones contained minute particles that gave them a milky aspect.

	Our next stop was Winza, where an important gem rush occurred in 2007−2008 (D. Schwarz et al., “Rubies and sapphires from Winza, central Tanzania,” Winter 2008 G&G, pp. 322−347; V. Pardieu, “The Winza ruby and sapphire mining area, Mpwapwa district, Dodoma province, Tanzania,” www.fieldgemology.org, 2009). The main mining area at Mtakanini was nearly deserted. An old rusted washing plant was visible, but due to mechanical problems it had not washed any stones in more than a year. We estimated that a handful of people were still mining around Mtakanini, mainly at primary deposits in underground tunnels, some of which were over 100 meters deep. Working conditions are difficult, as the rock is hard and the tunnels are prone to flooding. We learned that several brief ruby rushes occurred nearby at Godegode, Makutop, Magaseni, Singonali, and Berega. In Morogoro Province, two ruby and spinel mining areas have been exploited since the 1980s. One is located just east of Morogoro in the Uluguru Mountains, and the second is about 150 km south near Mahenge. Most of the gem trade in the Uluguru Mountain region is in Mkuyuni, while the mining takes place near Matombo, Ngongolo, Mwaraze, and Kibuko. In Matombo we witnessed about 30 people retrieving pink spinel and rubies from a secondary deposit near Kiswila. Near Ngongolo, we visited four small-scale operations where locals with hand tools were mining small rubies in marble associated with pyrite, graphite, and mica.

	Near Kibuko, a new pink sapphire deposit was worked by about 10 miners on a site owned by Luciano Kipanzi, who took over the area in 2015. Pink sapphires up to 100 carats are associated with carbonates and pyrite in a primary deposit (figure 2). Most of the stones were the milky “geuda” type, but there was some transparent facet-grade material with very fine crystallization. The mine had evidently yielded about 20 kg of sapphire, from cabochon- to facet-grade, during the previous six months. Nearby, three groups of small-scale miners were uncovering a limited amount of similar stones from secondary deposits.

Figure 2. Pink sapphires from the new deposit near Kibuko. Photo by Vincent Pardieu/GIA.

	The Mahenge district, known for spinel and ruby, is the second most active gemstone mining area in Tanzania. Recent discoveries of graphite near Ipanko and garnet near Lutela (the latter in February 2016) have kindled interest in the area. The new alluvial deposit produces an interesting range of attractive garnets (figure 3), from light “champagne” to deeper saturated rhodolite, including some color-shifting stones. We saw some clean stones weighing up to 20 ct and heard about others as large as 60 ct. About 100 miners were still working the alluvial deposit. Activity was already slowing; we were told that a few months earlier, up to 300 miners were in the valley. This secondary deposit is rapidly depleting, and so far no primary deposit has been located.

Figure 3. This garnet was mined from the new deposit in Lutela, Tanzania. Photo by Vincent Pardieu/GIA.

	Ipanko is still the main spinel deposit in the region. Author VP noticed that the pits were much larger than in 2012, meaning that the area had been mined since then. Nevertheless, the activity seemed slow compared to 2012: Several excavators were working secondary deposits, whereas small-scale miners once worked individual plots, called “boxes” by the locals. The nearby primary spinel deposit was still active, with about 400 people mining red spinel and only a few working on rubies. We then visited several small-scale ruby deposits along the Lukande River, including three operations working either primary or secondary deposits. As in the Uluguru Mountains, the rubies from these areas come from marble-type deposits. We saw about 50 miners working around Lukande, Kwam Somali, Mayote, Chipa, Ibogoma, Gombe, and Kitonga during the dry season, retrieving cabochon-grade rubies along with smaller facet-grade material. During the rainy season, these workers focus on gold mining or farming.

	Our last visit was the region around Songea and Tunduru, where sapphire production began in the 1990s. The Songea deposit, discovered in 1992, was quite productive until the discovery of fine blue, yellow, and pink sapphires near Tunduru in 1994. The deposit was nearly inactive until the early 2000s, when the newly developed beryllium diffusion treatment was able to turn Songea’s muddy green and brownish purple stones into attractive yellow to orange sapphires. In Songea, we heard of a new discovery at Amani Makoro, close to the old diggings around Ngembambili and Masuguru. In Amani Makoro, we witnessed about 200 miners in a swampy area using hand tools. The aspect and quality of the stones was similar to those from Ngembambili and Masuguru. Overall, about 300 people are still mining or trading gems around Songea. According to the regional mining officer, nine Thai merchants are registered buyers here. Songea still seems to be Tanzania’s most active sapphire mining area.

	The region east of Tunduru, located along the Muhuwesi, Lumesule, and Ruvuma rivers and up through Ngapa and Kitowelo, is known to produce blue, yellow, green, pink, and purple sapphires, and rarely rubies. The deposits, discovered by Swiss gem merchant Werner Spaltenstein in 1994, were very active until 1999, when buyers left Tunduru for the newly discovered sapphire deposits of Ilakaka, Madagascar.

	A paved road linking Tunduru to the coast and then Songea should be finished in 2017, making these areas much less isolated. Around Tunduru, a new environmental law that forbids mining within 60 meters of a stream or a river is creating issues, as most of the mining there takes place in riverbeds. Last year Mr. Spaltenstein had to stop his mechanized operation because of that law, though local authorities seem to be more tolerant of small-scale miners. While the area is much less active than when VP visited in 2005 and 2008, we estimate that about 400 to 500 miners are working around Tunduru. In the town, we found 10 Sri Lankan and three Thai buying offices. In the main gem-producing area there was a small rush in Ngapa, near Kitowelo and the area known as the “DSM Box” (figure 4). We were told the area produces some good blue, pink, and purple sapphire rough weighing up to 50 ct; fine sapphire of this size was previously unknown in Tunduru. The second most active place was Muhuwesi, where several groups of small-scale miners are reportedly working.

Figure 4. This blue sapphire rough, weighing about 7 ct, is from the new deposit at Ngapa, near Tunduru. Photo by Vincent Pardieu/GIA.

	The post-2009 downturn of Tanzania’s ruby and sapphire mining was not unexpected, because many of the corundum discoveries triggered rushes that were exploited for short-term gain. Tanzania also faces competition from the world-class ruby deposit in Montepuez. Nevertheless, recent colored stone discoveries point to the vast potential of gem mining in Tanzania. Source: GIA @topic:7


Title: Tourmaline Termination Abstract: Figure 1. Highlighted by blue and pink color accents, trigonal growth features are clearly visible on the surface of this 42.78 ct polished tourmaline termination. Photo by Kevin Schumacher.

	Depending on their size, large tourmaline crystals are known as “hand” or “cabinet” mineral specimens. To be used in jewelry, specimens of sufficient quality must be cut to a suitable size. This generally results in all of the natural surfaces being ground off and polished away. On occasion, however, a natural surface on a crystal is so interesting that it is preserved and used as a gem in its own right. Such was the case with a blue cap elbaite tourmaline (figure 1) from Fianarantsoa, Madagascar.

	During the cutting of this tourmaline, gem artist Falk Burger (Hard Works, Tucson, Arizona) saved the blue cap termination by sawing it off into a thin plate and mirror-polishing the sawn surface, thereby accentuating its remarkable trigonal growth features and pink and blue color zoning (figure 2, left). This resulted in the beautiful and unique designer gem seen in figure 1, which weighed 42.78 ct and measured 37.23 × 31.97 × 3.60 mm.

	Figure 2. Left: Using diffused transmitted light, contrasting pink and blue color zoning is seen. Right: Viewing the tourmaline through crossed polarizers and looking perpendicular to the polished plate, interference colors were clearly visible. Photomicrographs by Nathan Renfro; field of view 23.95 mm.

	This gem was also very interesting when examined through a microscope (figure 2, right). In crossed polarizers, while looking perpendicular to the polished plate, interference colors were clearly visible, accentuating the growth of the tourmaline. Source: GIA @topic:1


Title: Imperial Flame Topaz Sculpture Abstract: Figure 1. The Imperial Flame, a magnificent natural-color Brazilian topaz, was cut from a 615 ct crystal recovered some 20 years ago. The finished 89.53 × 20.56 × 19.15 mm sculpture weighs 332.24 ct. Photo courtesy of Sonja Kreis Unique Jewelry.

	One of the 2016 Tucson show’s most noteworthy gems was a 332.24 ct freeform Imperial topaz (figure 1) at the GJX booth of gem cutter Alexander Kreis (Sonja Kreis Unique Jewelry, Niederworresbach, Germany). Topaz with this red, pink, or orangy yellow color component is rare and highly sought after in the trade. Named the “Imperial Flame” by the Kreis family, the crystal was reportedly recovered from Brazil’s Ouro Preto topaz mines two decades ago. Topaz has been known from this area of Minas Gerais since 1768 (P.C. Keller, “The Capão topaz deposit, Ouro Preto, Minas Gerais, Brazil,” Spring 1983 G&G, pp. 12–20).

	Although mining was extensive at Ouro Preto in the mid-1990s (D.A. Sauer et al., “An update on Imperial topaz from the Capão mine, Minas Gerais, Brazil,” Winter 1996 G&G, pp. 232–241), the Kreis family confirmed that there is currently no large-scale mining. They visited the area after a collector informed them of a 615 ct crystal with exceptional color and clarity (figure 2). According to their contact, the crystal is “old production” mined at least 20 years ago. After analyzing the rough over a period of four months, the family purchased it in December 2015 with the objective of cutting the largest, highest-quality Imperial topaz known.

Figure 2. The original 615 ct Imperial topaz crystal from which Alexander Kreis fashioned the 332.24 ct Imperial Flame. Photo courtesy of Sonja Kreis Unique Jewelry.

	Due to the gem’s perfect basal cleavage, cutters must avoid grinding the stone perpendicular to the cleavage plane, while also accounting for inclusions that might cause the stone to break on the wheel. According to Sauer et al. (1996), well-formed, largely inclusion-free crystals typically yield up to 2 ct per gram (5 ct), which is a 40% recovery rate. Cutting the Imperial Flame took approximately eight days, spread over a period of 3–4 weeks, to allow Kreis to make trial carvings with smaller Imperial topaz pieces to test his cutting concepts. The cutting process began with sawing off the included portions and grinding to shape the solid crystal (figure 3), followed by faceting and carving to produce the reflective, grooved surfaces. The fashioning process yielded a spectacular gem measuring 89.53 × 20.56 × 19.15 mm. At 332.24 ct, it had a finished yield of 54%.

Figure 3. After trimming away included portions of the crystal’s base, Alexander Kreis gently removes any surface-reaching inclusions and begins to shape the crystal to his own unique design. Photo courtesy of Sonja Kreis Unique Jewelry.

	Intended as an arresting gem sculpture for a connoisseur or high-end collector, the piece is for sale. Source: GIA @topic:1