Publication Year: 2018 Title: Single HPHT Synthetic Diamond Mixed in Natural Diamond Ring Abstract: Figure 1. The ring with 194 natural diamonds and one HPHT-grown specimen. Photo by Nazar Ahmed Ambalathveettil.

Recently, a ring with 195 mounted colorless and near-colorless stones (figure 1) was submitted to Dubai Central Laboratory for identification. The ring contained round-brilliant-cut diamond melee arranged in rows. Testing with the DiamondSure instrument identified 194 of them as natural diamond, and the remaining melee was referred for further testing.

Figure 2. These metallic flux inclusions that are associated with feathers show high reflection in oblique light. Photo by Nazar Ahmed Ambalathveettil.

Figure 3. The laboratory-grown diamond fluoresced yellow under long-wave UV (left) and greenish yellow under short-wave UV light (right). Photos by Nazar Ahmed Ambalathveettil.
The sample’s setting in the ring restricted us to FTIR spectroscopy in reflection mode to determine its identity. Solid metallic inclusions were revealed under the microscope (figure 2). The specimen displayed strong yellow and moderate greenish yellow fluorescence under long-wave UV and short-wave UV, respectively (figure 3). The inclusions and fluorescence suggested HPHT-grown diamond, which generally shows a stronger fluorescence reaction to short-wave UV than to long-wave UV. The vast majority of HPHT synthetics in the “colorless” range exhibit no detectable fluorescence to long-wave UV (S. Eaton-Magaña et al., “Observations on HPHT-grown synthetic diamonds: A review,” Fall 2017 G&G, pp. 262–284), but this one showed strong fluorescence under long-wave UV.
The stone was further examined with DiamondView imaging and photoluminescence (PL) spectroscopy. Strong yellowish green fluorescence and blue phosphorescence were observed with the DiamondView, but the growth sector pattern typical of HPHT-grown diamond was not visible because of the stone’s size. PL spectroscopy showed nickel-related peaks at 882/884 nm. Based on these results, we concluded that this was an HPHT laboratory-grown diamond.
We later learned that the customer had given the ring to a jewelry repair shop to replace a broken diamond, which may account for the single lab-grown specimen. This is a good example of the need for vigilance in every stage of diamond jewelry making. @chapter:15


Publication Year: - Title: Morganite Care and Cleaning Abstract: Morganite is a durable gemstone. With proper care, it will provide a lifetime of jewelry-wearing enjoyment. -Courtesy of The Greenwood Group.

                      Gem and mineral hardness is measured on the Mohs scale. The numbers are based on the relative ease or difficulty with which one mineral can be scratched by another. But the Mohs scale is deceptive. The steps between the minerals are not evenly spaced. For example, diamond is only one number away, but it’s many times harder than gems in the corundum family. Morganite is 7.5 to 8 on the Mohs scale, so it is a durable gemstone for jewelry as long as it is treated with care to protect it against scratching and hard knocks.

	Morganite rates a 7.5 to 8 on the Mohs hardness scale.

Stability
Heat exposure is not recommended for morganite, but under light exposure, its color is stable and won’t fade. Morganite can be attacked by hydrofluoric acid.

Cleaning
Warm, soapy water is always a safe cleaning method for morganite. Cleaning by ultrasonic and steam cleaners is usually safe, unless the stone has liquid inclusions or fractures.
Rarely, morganite might be fracture filled. These stones should only be cleaned with warm, soapy water.

Fracture-filling @chapter:23


Publication Year: 2010 Title: New Occurrence of Fire Opal from Bemia, Madagascar Abstract: Twenty-two gem opals from a new volcanic deposit located near Bemia, in southeastern Madagascar, were investigated by classical gemological methods, SEM-EDS, powder X-ray diffraction analysis, LA-ICP-MS, and Raman and IR spectroscopy. Although none of the opals show play-of-color, they exhibit a wide variety of hues—including those typical of fire opal—that are related to iron content, mainly from Fe-rich inclusions. Consistent with their volcanic origin, these samples are microcrystalline and composed of opal-CT or opal-C. Among the inclusions are ilmenite needles, clay minerals, and iron oxides and hydroxides. The RI and, in particular, SG values are higher than those typical of natural fire opal (e.g., from Mexico) and some synthetic fire opal, allowing for a rapid separation. @chapter:39


Publication Year: 2013 Title: Study Helps Identify Nepalese Kyanite Abstract: Blue kyanite has long been used as a sapphire imitation. At a glance, bright blue kyanite from Nepal might be mistaken for sapphire, but they are easily identified by their different inclusions and optical values.

	An article by Ulrich Henn and Klaus Schollenbruch titled “Saphirblauer Disthen (Kyanite) aus Nepal [Sapphire-blue kyanite from Nepal]," published in Gemmologie: Zeitschrift der Deutschen Gemmologischen Gesellschaft (Vol. 61, No. 3, 2012, pp. 91–98), describes the properties of kyanites from two occurrences discovered in 1995 in Nepal and compares them with gems from other deposits. Nepalese kyanite has been produced since 1999 in small-scale mining operations near Daha and Suneri and near Jajarkot and Barah, all west-northwest of Katmandu. Along with material for cabochons and beads, greater quantities of calibrated and larger faceted stones have appeared in the market in recent years. Only a very small percentage of the material is facetable.

	The bulk of the article presents the findings of the author's investigation of kyanites from Nepal. While the nx and nz values of the refractive index lie within the range of kyanites from other sources, the ny value is distinctly lower. These are in accordance with a biaxial positive optical character, whereas kyanite is normally described as biaxial negative. The specific gravity of 3.65 to 3.68 g/cm3 is also equivalent to that of stones from other occurrences.

	The chemical composition, determined by EDAX, showed trace contents of iron, vanadium and titanium in concentrations similar to those in stones from other sources. The blue color is due to the iron and titanium contents, while the vanadium does not seem to influence the color. Traces of chromium appear to be responsible for the fluorescence of some stones. The authors also discuss the absorption spectra and the mechanisms that lead to different colors as well as color change and fluorescence.

	Microscopic inspection reveals the whole spectrum of phenomena and inclusions that are also found in kyanites from other sources: large cleavage fractures, growth tubes, liquid inclusions and black crystals. With oblique illumination, all of these inclusions can produce iridescence. Additionally, many kyanites show strong color zoning.

	While the introduction of the article is just a summary of general information familiar to every gemologist, the results of the investigation are a welcome addition. With the different optical characters and ny values, it is even possible to separate Nepalese kyanites from those of other sources. @chapter:5


Publication Year: - Title: Tourmaline Quality Factors Abstract: This 3.28-carat Paraíba tourmaline's vivid violetish blue hue rivals the finest sapphires. Because of this tourmaline's rarity, its per-carat price is also likely to rival the price of fine sapphire.

Color
One of tourmaline’s most sought-after and generally available colors is the pink/red variety known in the trade as rubellite.

	Tourmaline's hue and depth of color can approach the range of ruby and pink sapphire. This 8.16-carat cushion-shaped rubellite and 10.78-carat emerald cut pink tourmaline are superb examples.
Green tourmaline’s pastel hues provide the market with pleasing alternatives to the deep, rich hue of emerald and the softer green of peridot.  At their best, green tourmalines are transparent, brilliant, and clean, with attractive bluish green hues.

Most green tourmalines are strongly pleochroic. Stones that show attractive colors in both directions—such as bright green in one and blue in another—are the most valuable.

Chrome tourmaline gems offer hues that are more saturated than most green tourmalines. Chrome tourmaline can be a lower-priced alternative to tsavorite or emerald. Both these gems are rare in sizes above two carats, but it’s not hard to find chrome tourmaline in sizes up to five carats. And, while tourmaline can’t match tsavorite’s luster or brilliance, it’s far less expensive than a tsavorite of equivalent size and quality.

Dark-toned stones—which are more common in the marketplace—aren’t very attractive. Some absorb light so intensely that they appear almost black from certain directions. Cutters typically fashion these stones with the table parallel to the length of the crystal. Gems cut this way might show a less attractive brownish or yellowish color through the crown. Dealers frequently describe these gems as “oily” or “olive” green. Their prices are much lower than the prices for fine green tourmaline or brighter bluish green tourmaline.

	This 11.47-carat cushion-shape from Landanai, Tanzania, is a classic example of chrome tourmaline. Its high clarity, medium-dark tone, and strong green hue make it highly desirable.

	This 8.76-carat emerald cut tourmaline’s medium tone and strongly saturated, slightly yellowish green hue make it very marketable.

	High clarity, medium-light tone, and strongly saturated bluish green hue are the hallmarks of this 5.43-carat emerald cut tourmaline from Tanzania.
Blue tourmaline can range in tone from light to dark. The hue is often modified by green so you can have a blue color with just a little bit of green modifying color or a color that is very greenish but still blue. Some tourmalines have an even amount of green and blue to the color. Like green tourmaline the blue colors can be strong and vivid or less saturated and grayish.

	This 1.80-carat rectangular step cut tourmaline from Russia is medium light in tone and has a slightly greenish blue hue with moderately strong saturation. This is a noteworthy combination for a blue tourmaline.

	This 9.91-carat Afghan tourmaline hovers on the boundary between green and blue hues. Its high clarity and medium tone give it a pleasing appearance.

	This 5.19-carat medium-dark, very strongly greenish blue emerald-cut tourmaline is from Namibia.
Since it was discovered in the late 1980s, Paraíba tourmaline’s striking neon blues and greens have electrified the gem world. The gem’s unique, vivid coloring instantly set it apart from other tourmalines. Initial worldwide reception to the gem was wild, especially in Japan, where demand for fine-colored stones was insatiable.

Prices for this exotic newcomer—especially top quality in sizes between 3.00 and 5.00 carats—climbed rapidly to over $10,000 per carat. No tourmaline—even prized rubellite reds and chrome greens—had ever achieved such heights in value. Paraíba tourmaline’s rarity undoubtedly contributes to its high prices.

	Fashioned Tourmaline can be found in large sizes. This magnificent stone weighs 45.31 carats and boasts natural, untreated color. Photo: Katharina Mint Ring © 2011 Fabergé Ltd.
The gem is an elbaite tourmaline that comes from one area of Paraíba state in Brazil’s northeast corner. Like many other Brazilian elbaites, Paraíba tourmaline forms in pegmatite. But researchers believe that its crystals form under very unusual conditions, with large amounts of trace elements like manganese and copper, which causes its color. Paraíba tourmaline is unusual because, although copper colors some other gems—notably turquoise—it’s not a coloring agent in any other tourmaline.

In some specimens, there’s so much copper that inclusions of native copper—almost pure metal—highlight the gem’s interior. Scientists speculate that the native copper inclusions took shape in the early stages of cooling, after the gems started to crystallize.

Paraíba tourmalines appear in a range of greenish blue, bluish green, green, blue, and violet hues. Although buyers covet all these colors, blue and violet have the most appeal. Dealers use a number of names to try to capture the extraordinary quality of Paraíba tourmaline’s colors. Besides neon, they use terms like “electric,” “turquoise,” “sapphire,” or “tanzanite” blue, and “mint” green.

	The Paraíba deposit revealed a range of new tourmaline colors unrivaled for their strongly saturated hues and light to medium tones. Representing the color range are a 2.59-carat turquoise-blue triangle cut, a 3.28-carat electric-blue pear shape, and a 3.68-carat green pear shape.
Overall, prices for the best Paraíba tourmalines easily surpass other tourmalines due to their more attractive hues, higher color saturation, and greater rarity. A direct comparison with other tourmalines makes the difference obvious. Compared to any other green tourmaline, for example, a green Paraíba tourmaline will have a more saturated hue and lighter tone.

Because of the rough’s high value, Paraíba tourmalines are almost always custom cut. They’re usually faceted into brilliant cuts, commonly pear and oval shapes. You’ll rarely see Paraíba tourmaline in sizes bigger than one carat. With Paraíba, however, color is the key factor, not size. So if a dealer has to choose between a larger stone and a more vividly colored one—all other factors being equal—the gem with the better color is a better choice.

Copper-bearing tourmalines that resemble the vibrant, intense colors of the gems found in Brazil’s Paraíba region have also been found in other parts of the world. An article in the Spring 2008 issue of GIA’s Gems & Gemology scientific journal describes the copper-bearing gems of Mozambique. Nigeria has been a source of these striking gems as well.

During Paraíba tourmaline’s brief history, dealers have often resigned themselves to the gem’s extreme scarcity. However, new discoveries elsewhere in Brazil and eastern Africa present the possibility that viable, commercial sources of this rare copper-bearing tourmaline might one day supply the trade with more material. Unfortunately, the new sources also raise questions about the use of the term Paraíba to name these treasured gems.

	The discovery of significant copper-bearing tourmaline deposits in Mozambique
	increased availability and broadened the appeal for this gem. This 14.53-carat heated
	gem is mounted in a striking pendant with black and red spinel, yellow sapphire, tsavorite,
	and diamond accents. - Courtesy Carley McGee-Boehm, Carley Jewels

	Sources in Nigeria produce a vivid array of copper-bearing tourmalines. These stones range in size from 0.31 carat to 1.04 carats. - Courtesy Barker & Co.
Watermelon, bicolor, and multicolored zoning occurs when the trace elements change in concentration or composition during a crystal’s growth. Liddicoatite can show striking and complex zoning, and gems are often fashioned to showcase exotic color combinations. Gemologists describe these tourmalines as parti-colored.

	This 11.21-carat bicolor tourmaline is a supreme example of both the gem material and the cutter's art. The stone has intense colors, a clean junction between the zones, and the highest clarity. - Lydia Dyer, gem courtesy of John Dyer & Co.

	This Brazilian crystal is a typical watermelon tourmaline, with a pink core surrounded
	by a thin green skin. The colors are best shown in thin slices, which are well suited to
	one-of-a-kind jewelry pieces. - Courtesy Brasgemas
Sometimes tourmalines are color-zoned across the length of the crystal: A crystal that starts off as pink might end up with a green tip. Or they can be zoned parallel to their length, so that a red crystal might end up with a green overgrowth. Dealers call these watermelon tourmalines because their colors resemble the rind and flesh of that fruit. Designers sometimes exploit the look of watermelon tourmaline by setting slices of the crystal rather than faceting the rough.

Clarity
Colored tourmalines grow in an environment rich in liquids, and some of those liquids are often captured as inclusions during crystal growth. The most typical inclusions resemble thread-like cavities that run parallel to the length of the crystal. Under magnification, you can see that they’re filled with liquid or gas bubbles. Growth tubes—long hollow tubes often capped with minute mineral crystals—are also common tourmaline inclusions. If they’re numerous enough, and the rough is correctly cut, they can cause a cat’s-eye.

	The gems in this remarkable suite of cat’s-eye tourmalines are all from Brazil. Inclusions
	cause the cat’s eye effect and add value. - © GIA and Harold & Erica Van Pelt
Dealers usually tolerate red tourmalines with some eye-visible inclusions as long as the color is strong and attractive. Inclusions that reach the surface interfere with luster and polish and make gems harder to sell. And although liquid inclusions are less visible in stones of intense color, stones with prominent whitish inclusions—no matter how vibrant the color—are undesirable.

Inclusions are much more visible in gems with light tone and low saturation. Since these stones don’t have strong and attractive color to compensate for the inclusions, most buyers reject the ones with eye-visible inclusions. Many included tourmalines with good color are cut as cabochons to emphasize the color and minimize the appearance of the inclusions.

It’s not unusual for pink and red tourmalines to have eye-visible inclusions. Unless their size or the number of the inclusions is distracting, knowledgeable consumers consider the color to be the dominant value factor. Green tourmalines are expected to be free of eye-visible inclusions so distracting inclusions can lower the value of the green gems. For the other colors, tourmalines with no eye-visible inclusions are more valuable than those with inclusions that can be seen. The more visible any inclusions are, the more the value drops.

Cut
The elongated shape of many tourmaline crystals has a direct impact on the finished gem’s shape and proportions. As a result, there are many narrow, non-standard sizes available. Although some are very attractive, many gem buyers prefer stones with standard dimensions because they’re easier to set in standard mountings.

	Jewelry designers create custom mountings to accommodate the shape of fashioned tourmalines. - © GIA & Tino Hammid, courtesy Chris Almquist
Cutters often fashion tourmalines as long rectangles. Making the cut parallel to the length of the rough crystal helps to reduce waste. But cutters also have to consider tourmaline’s optical properties.

Tourmaline is strongly pleochroic, which means that it can show different colors in different crystal directions. One of tourmaline’s pleochroic colors is typically much darker than the other. In addition, many tourmalines absorb more light down the length of the crystal than across it. So a crystal that appears pale green across its length can be very dark green—sometimes almost black—when you look down its length.

Rather than cutting every tourmaline lengthwise, many cutters orient a fashioned gem based on its depth of color. To darken pale rough, they might orient a gem’s table so it’s perpendicular to the crystal’s length. To lighten dark rough, they orient a finished gem’s table so it’s parallel to the crystal’s length.

Carat Weight
Fashioned tourmalines in larger sizes rise considerably in per-carat price. Even though specimens can reach spectacular sizes, these are rare. Availability drops and prices rise sharply for facet-quality rough material. For fashioned gems of similar color and clarity, the price per carat generally increases as the gems pass the five-carat milestone.

	Large tourmaline crystals are often fashioned by gem sculptors into special pieces for clients looking for the unusual. Renowned Idar-Oberstein gem cutter Bernd Munsteiner fashioned this 11.18-carat blue-green gem in his unique style. @chapter:3


Publication Year: 2024 Title: Irradiated and Dyed Akoya Pearls Abstract: Figure 1. The two groups of reportedly irradiated akoya pearls used in this study. Photos by Sood Oil (Judy) Chia.
Since the 1960s, irradiation has been a known treatment for modifying the color of freshwater cultured pearls (Developments and Highlights at the Gem Trade Lab in Los Angeles, Spring 1967 G&G, pp. 153–154). It was found that freshwater shells and pearls contained higher amounts of manganese, which could be oxidized by irradiation to produce a darkened color (T. Tsujii, “The change of pearl colors by the irradiation with γ-ray or neutron ray,” Journal of Radiation Research, Vol. 4, No. 2-4, 1963, pp. 120–125). While saltwater pearls contain much less manganese than freshwater pearls, cultured saltwater akoya pearls could also be treated with irradiation. During treatment, the freshwater shell bead nuclei inside these cultured pearls would turn darker and cause the surface color, luster, and overtone to change (Winter 1988 Gem Trade Lab Notes, p. 244).
Recently, GIA’s New York laboratory obtained two groups of reportedly irradiated akoya pearls from two different vendors. These samples were either drilled or partially drilled, ranging from 3.82 mm to 8.15 mm in diameter and from 0.29 to 3.58 ct in weight (figure 1). They exhibited a variety of light to dark-toned gray with bluish and greenish bodycolors, with variously colored overtones.

Figure 2. Images showing obvious color concentrations at the drill holes of some samples with darkened bead nuclei (A and B), an unnatural dark patchy surface (C), and a darkened bead nucleus without color concentration (D). Photomicrographs by Emiko Yazawa; fields of view 4.79 mm (A and C) and 3.57 mm (B and D).
Real-time X-ray microradiography and energy-dispersive X-ray fluorescence confirmed that these were bead cultured pearls grown in a saltwater environment. No silver content was detected on any of the surfaces, suggesting that the colors of these pearls had not been modified by silver nitrate treatment. Upon microscopic examination, however, some of the samples displayed obvious color concentrations at their drill holes or unnatural patchy surface color distributions, while also revealing a darkened bead nucleus inside. On the other hand, some light-colored pearls did not possess color concentrations at the drill hole and only contained a darkened bead nucleus (figure 2).

Figure 3. Left to right: Cross sections of an irradiated akoya pearl, a white akoya pearl, and an irradiated and dyed akoya pearl. Photo by Emiko Yazawa; field of view 14.52 mm.
To further investigate the color origin, we cut several samples as well as a typical white akoya cultured pearl to compare their internal appearances (figure 3). The results confirmed that the reportedly irradiated pearls contained darkened bead nuclei showing brownish stripes rather than the usual white bead nucleus found in a white akoya pearl, indicative of irradiation treatment (Winter 1988 Gem Trade Lab Notes, p. 244). In addition, some samples exhibited a distinctly different color appearance at the nacre and drill-hole areas, indicating dye treatment.

Figure 4. Raman spectra of one sample’s surface nacre, nacre on the cross section, and bead nucleus, along with the surface nacre of a white akoya pearl for comparison. Unusual peaks were found in both nacre areas but not on the bead nucleus. Also shown are typical aragonite features at 702, 704, and 1086 cm–1.
Short-wave UV fluorescence spectroscopy confirmed that the akoya pearls may have been treated by any number of processes (C. Zhou et al., “Detection of color treatment and optical brightening in Chinese freshwater ‘Edison’ pearls,” Summer 2021 G&G, pp. 124–134), based on low fluorescence counts at around 320–360 nm. Raman spectroscopic analyses using 514 nm laser excitation revealed aragonite as the main component. Some treated pearls exhibited a series of unusual Raman shift peaks between 560 and 3200 cm–1 on the nacre (probably due to dye materials) but not on the darkened shell bead nucleus, suggesting two forms of treatment: dyeing and irradiation (figure 4).
Naturally colored gray pearls are usually light in color and tend to show uneven color distribution, making them difficult to match. Some grayish akoya pearls on the market have been treated to imitate these natural colors, since they command higher prices. While dye treatments are more easily detected by unnatural bodycolors, obvious color concentrations, and advanced testing, irradiation treatment is harder to detect since the nacre is not affected and the difference in bodycolor is subtle. Careful visual observation is necessary. The combination of irradiation and dye treatments in some of these treated pearls is not commonly encountered in our laboratory. @chapter:14


Publication Year: 2022 Title: Rare Kashmir Star Sapphire Abstract: Figure 1. An approximately 15 ct blue Kashmir star sapphire set in a combination ring and pendant with near-colorless pear and marquise brilliants. Photo by Annie Haynes.
A rare star sapphire of Kashmir origin, mounted in a combination ring and pendant (figure 1), was recently examined in the New York laboratory. Kashmir has long been regarded as the most sought-after source of blue sapphire since the deposit’s discovery in the late nineteenth century. Words such as “sleepy” or “velvety” are often used to describe their characteristic appearance, which can be attributed to the scattering of light as it interacts with “milky” bands of microscopic particles within the stone. Due to the locality’s limited production, Kashmir sapphires are scarce in the market, and star sapphires are particularly uncommon (R.W. Hughes et al., Ruby & Sapphire: A Gemologist’s Guide, 2017, RWH Publishing/Lotus Publishing, Bangkok, p. 477).

Figure 2. Wispy stringers among sharp milky bands of microscopic particles. Photomicrograph by Emily Jones; field of view 3.57 mm.
This blue cabochon star sapphire was estimated to weigh around 15 ct. A spot reading gave an approximate refractive index of 1.76, matching corundum. Microscopic inspection revealed sharp, angular milky bands and particle streamers (figure 2), both features that are typical of Kashmir sapphires. Several sparse short silk needles were also observed (figure 3). Asterism in corundum is generally caused by the reflection of light off of exsolution rutile silk needles. This sapphire’s star, however, was generated by light reflected from the crystallographically oriented bands of minute particles.

Figure 3. Several short needles of exsolution silk amid the abundant particle stringers. Photomicrograph by Emily Jones; field of view 1.85 mm.
Further testing of the sapphire’s spectral and chemical properties was carried out to help determine its geographic origin. Laser ablation–inductively coupled plasma–mass spectrometry revealed a trace element chemistry consistent with stones of known Kashmir origin, based on GIA’s internal reference data. This, coupled with the material’s internal characteristics, confirmed that the star sapphire was in fact from Kashmir. No evidence of heat treatment was detected. While the majority of corundum on the market is heated to improve color, high-quality sapphires from Kashmir are generally left untreated.
Kashmir sapphires are rare enough in their own right. Furthermore, a large star sapphire from this historic locality is truly an extraordinary sight, and certainly a first for the author. @chapter:19


Publication Year: 1982 Title: The Chanthaburi-Trat Gem Field, Thailand Abstract: With the recent drastic decline in production from the classic ruby mines of Burma, Thailand has become the world's major source of gem ruby. The majority of the ruby production, as well as some significant sapphire production, comes from the provinces of Chanthaburi and Trat in southeastern Thailand. This article reviews the geology of these alluvial deposits and describes the wide range of methods used to mine the corundum. Gemologically, the Thai rubies are distinguished by their violet overtone, inhibited fluorescence, and characteristic inclusions. Also discussed is the heat treatment of corundum to enhance color, which has become a major industry in Chanthaburi. The newest product, "golden" sapphire, is examined, including the apparent stability of the color produced and clues to the detection of the heat treatment. @chapter:3


Publication Year: - Title: Bill Boyajian Abstract: Bill Boyajian, president of GIA from 1986 to 2006, is known for a vision that took the Institute to its global position. His path to the gem and jewelry industry began during college, when he was offered a job at the jewelry counter of a local department store. He soon discovered a love of jewelry and gems and a desire for a career in the industry. His boss told him that GIA was the starting point, and he began classes three weeks after graduating.

	About his first diamond class, taught by Jim Lucey, Boyajian said, “I knew then what I was going to do—I wanted to be like that man and teach that class!” He applied for a job at GIA just before finishing his G.G. in 1975 and began teaching at the Santa Monica campus in 1976.

	Over the next several years, Boyajian’s positions included instructor, grader, colored stone program supervisor, manager of new product development, and marketing manager. Then in 1986 the Board of Governors selected him to become president when Glenn Nord stepped down for health reasons. Boyajian was only 34 years old, but Nord and his predecessor, Richard Liddicoat, had long seen him as the person to lead the Institute into the next century. “He had a total belief in what GIA can do for the industry and a dedication to gemology,” Nord said.

	A self-described idealist, Boyajian is recognized for his management and marketing skills and his talent for inspiring others. He was the first to initiate long-range strategic planning with the GIA Master Plan in the 1980s, and he began GIA’s global education expansion. The size of the laboratory more than doubled under his leadership, and he oversaw the move to the Carlsbad campus in the mid-1990s. He also initiated GIA’s colored stones grading system. A noted speaker and writer, he has lectured and published extensively, including authoring or coauthoring 19 articles for Gems & Gemology.

	Since leaving the Institute in 2006, Boyajian has consulted for jewelers and other businesses and published a book on leadership. His industry recognition includes the Diamond Industry Steering Committee Hall of Fame (1998), the National Conference for Community Justice Humanitarian Award (1998), an AGTA Honorary Life Membership (1999), the AGS Circle of Distinction (2002), the WJA Ben Kaiser Award for Excellence (2005), and the American Gem Society’s Robert M. Shipley Award (2013).

	“I put no limits on what I or GIA can do,” Boyajian told Jewelers’ Circular Keystone during his tenure at the Institute. “What’s necessary today is to serve a cause that will last a lot longer than any of us. That is the ultimate motivator.” @chapter:33


Publication Year: 2015 Title: Large Natural Quahog Pearl Abstract: Figure 1. This northern quahog pearl exhibited a fine color and shape. Photo by Jian Xin (Jae) Liao.

A notable purple non-nacreous pearl (figure 1) recently submitted to GIA’s New York laboratory measured 13.69 × 11.80 mm and weighed 16.64 ct. It was immediately recognizable as an outstanding specimen due to its clean surface, which possessed an attractive sheen reminiscent of fine porcelain. It had good symmetry, featuring a near-round button shape with a perfect dome top and a rounded base, and a richly saturated and well-distributed mid-purple color.

Real-time microradiography revealed a tight internal structure, a common characteristic of certain natural non-nacreous/porcelaneous pearls. Raman spectroscopy using 514 nm laser excitation (figure 2) showed characteristic aragonite peaks at 702, 706, and 1086 cm–1, as well as 1130 and 1520 cm–1 peaks related to a mixture of polyenic (polyacetylenic) compounds, the natural pigments responsible for its purple color, as previously observed in similar pearls (Winter 2008 GNI, pp. 374–375). The characteristic natural purple color and non-nacreous porcelaneous appearance indicated a pearl from the bivalve mollusk Mercenaria mercenaria (belonging to the Veneridae family), also referred to as the “northern quahog.”

Figure 2. The quahog pearl’s Raman spectrum showed the typical aragonite peaks
seen in most pearls, together with 1130 and 1520 cm–1 peaks related to a natural
coloring compound.
Quahogs are native to the Atlantic shores of North America from Canada to Georgia, especially on the coast of the New England states, and can also be found along California’s Pacific coast. They can produce non-nacreous porcelain-like pearls, and their shells typically exhibit an uneven white and purple interior color (figure 3). Quahog pearls may occur in a variety of colors ranging from white to brown and from faint pinkish purple to dark purple. Like other natural pearls, quahog pearls are rarely spherical. Button shapes with flat bases are most often encountered.

Figure 3. This quahog shell from the eastern coast of the United States has a naturally attached pearl. Photo by Robert Weldon.
Natural northern quahog pearls are often submitted to GIA labs. Most are below 10 carats with a flat-based button shape, usually with a dark or light purple color, and tales of their accidental discovery while eating clams are not uncommon. This quahog pearl’s large size, clean surface, fabulous luster, near-round shape, and evenly distributed rich color combine to make it an exceptionally fine and rare example of its type. @chapter:14


Publication Year: - Title: Winter 2022 G&G Available Now Abstract: The Winter issue features three studies on identifying treatments in colored gemstones—ruby, feldspar, and turquoise—and introduces us to an inspirational artist and pioneer in the jewelry industry. In addition to the four feature articles and our quarterly sections, we see the return of Colored Stones Unearthed.
A CANARY IN THE RUBY MINE: LOW-TEMPERATURE HEAT TREATMENT EXPERIMENTS ON BURMESE RUBY
E. Billie Hughes and Wim Vertriest conduct low-temperature heating experiments on Burmese ruby. The appearance of inclusions at each heating step, coupled with spectroscopic analysis, provides evidence of this treatment. Particular solid inclusions proved sensitive to low-temperature heating.
FLUORESCENCE CHARACTERISTICS OF TWO COPPER-DIFFUSED PLAGIOCLASE FELDSPARS: LABRADORITE AND ANDESINE
For this study, Qingchao Zhou and fellow researchers treated colorless labradorite and light yellow andesine with copper diffusion to mimic the color of natural labradorite sunstone. They discovered that fluorescence emission characteristics under 320 nm excitation can potentially help identify copper diffusion treatment in a material that has been a subject of controversy for decades.
COMPOSITION AND SPECTRAL CHARACTERISTICS OF PORCELAIN-TREATED TURQUOISE
A team led by Liying Huang uses a combination of low specific gravity, strong luster, high silica content, and surface features to effectively identify the novel “porcelain” treatment technique. This treatment method improves the luster and color of low- to medium-quality turquoise to meet the demand for scarcer high-quality natural turquoise in the Chinese market.
NEVER STOP INNOVATING: GEM ARTIST CHI HUYNH
Tao Hsu and coauthors visit Chi Huynh, founder and owner of Galatea: Jewelry by Artist, who shares his experiences and passion for jewelry-making innovations. Carved pearls, gem bead cultured pearls, and two-way shape-memory jewelry are but a few of the groundbreaking jewelry design concepts he employs in his finished pieces.
LAB NOTES
GIA’s global laboratory staff present their latest findings in the Lab Notes section, including a unique chrysoberyl displaying four-rayed asterism, the largest cat’s-eye emerald examined by GIA to date, and the identification of two non-nacreous bead cultured pearls from Pinctada margaritifera.
MICRO-WORLD
The Micro-World section, dedicated to the inner world of gemstones, features unusual “horsetail” and columnar inclusions in demantoid, a bluish green omphacite crystal in colored diamond, and aegirine inclusions in poudretteite from a new deposit in Mogok.
COLORED STONES UNEARTHED
Colored Stones Unearthed returns to examine gem minerals that form in magmatic environments, such as diamond, garnet, spinel, and corundum. Through these gems, gemologists gain insights into the generation of magmas within the earth, their transport to the surface, and modes of volcanic processes after eruption.
GEM NEWS INTERNATIONAL
Finally, GNI’s global contributors report on a variety of topics, including an extremely rare hellandite inclusion in ruby from Mogok; the identification of natural, reconstructed, and imitation Burmese root amber; and a roundup of the fall 2022 auction highlights, which had several surprising twists. @chapter:0


Publication Year: 1993 Title: Jewels of the Edwardians Abstract: Although the reign of King Edward VII of Great Britain was relatively short (1902-1910), the age that bears his name produced distinctive jewelry and ushered in several new designs and manufacturing techniques. During this period, women from the uppermost echelons of society wore a profusion of extravagant jewelry as a way of demonstrating their wealth and rank. The almost exclusive use of platinum, the greater use of pearls, and the steady supply of South African diamonds created a combination that will forever characterize Edwardian jewels. The Edwardian age, truly the last era of the ruling classes, ended dramatically with the onset of World War I. @chapter:16


Publication Year: 2024 Title: The Appeal of Non-Nacreous Pearls Abstract: Figure 1. Necklace featuring 37 conch pearls accented by 32 diamonds. Photo by Robert Weldon; courtesy of Aloha Pearls Hawaii.
Pearls never disappoint at the AGTA and GJX shows, and this year was no exception. While quantities were lower, a good supply of Tahitian, freshwater, and South Sea pearls was available. AGTA hosted a booth sponsored by Martin Rappaport featuring nacreous natural pearls from Bahrain, complete with reports from DANAT, the Bahrain Institute for Pearls & Gemstones. Of particular interest was a wide selection of natural non-nacreous pearls.
Several vendors at GJX offered non-nacreous conch pearls, with a smaller selection available at the AGTA show. Alec Rupp-Smith of Aloha Pearls Hawaii showed a fabulous graduated, mixed-color conch pearl necklace (figure 1) at both the GJX and Pueblo shows. The necklace featured 37 conch pearls with a total weight of 179 carats. Thirty-two diamonds, 9.06 carats total, were used as accents to the suite of pearls.

Figure 2. Melo “half pearl” weighing 57 ct. Photo by Robert Weldon; courtesy of Aloha Pearls Hawaii.
Rupp-Smith also presented an interesting Melo pearl from Myanmar (figure 2). The pearl was clearly cut in half, with the other half likely fabricated into jewelry. The remaining 57 ct half was polished to display the fine concentric rings used to help separate bead-nucleated cultured pearls from their natural counterparts, without the need for X-ray tomography. The banding was visible even without a loupe.
Somewhere in the Rainbow returned to the AGTA show to highlight recent acquisitions to their ever-growing collection. The mission of the collection is to bring education and enjoyment of fine colored gems to museums, galleries, and facilities dedicated to preserving the rarity and beauty of these minerals, gems, and articles of jewelry. The collection features pearls and colored stones from a wide contingent of designers from around the world. This year, three non-nacreous pearl creations stood out, sourced from Carlos Chanu, owner of California-based PCD Pearls.

Figure 3. Left: Cassis pearl necklace and convertible ring/brooch designed by Jim Grahl. Right: “Golash” brooch featuring fine quahog pearls. Photos by Robert Weldon; courtesy of the Somewhere in the Rainbow collection.
The first was a Cassis pearl suite consisting of a graduated necklace and convertible ring/brooch all fabricated in 18K gold and platinum by designer Jim Grahl of Balboa Island, California (figure 3, left). Chanu sourced the pearls from Europe over the course of one year. The layout of the necklace took a month to get just right, with a nicely matched blend of size, shape, and color. The ring/brooch pearl is one of the finest examples of Cassis known.
The second is the “Golash” brooch in figure 3 (right), named after the man who purchased it at an antique store in 2000 for $14, dates back to 1835 and was fabricated in the state of Rhode Island. Two rare quahog pearls (Mercenaria mercenaria) are set in the piece. At 13.5 ct and 13 mm, the larger, slightly button-shaped pearl has a glass-like surface and stunning color that make it an exceptional natural quahog pearl. Mercenaria pearls are rare, found as a byproduct of the clam fishing industry on the East Coast of the United States. The smaller, near-perfect drop-shape pearl measures nearly 9 × 7 mm and weighs 2.89 ct. Uniform natural drop pearls are among the rarest for any mollusk. As part of an international pearls exhibition, the “Golash” brooch toured the world from 2001 to 2008.

Figure 4. Quahog (Mercenaria mercenaria) pearl suite offered at the GJX show. Photo by Robert Weldon; courtesy of Pacific Coast Pearls.
Pacific Coast Pearls (Henderson, Nevada) brought an impressive array of natural pearls to GJX this year. After owner Wes Rankin found his first abalone pearl while diving off the coast of California, he spent the next decade collecting and purchasing pearls. This led to what has become one of the largest selections of natural pearls on the market today. At the show, co-owner Tish Rankin assembled an extraordinary suite of quahog pearls, just waiting for the right designer and inspiration to come along (figure 4). If only the humble clam had known. @chapter:14


Publication Year: - Title: Alumni Members Across the Globe Offer Guidance, Support Abstract: Chapter leaders from the Monterrey-Mexico chapter, from left, Perla Solis, treasurer, Daniela Califa, vice president, and  Melissa Villarreal, president and founder. The chapter hosted a Gema-Cinema event, featuring a documentary on jewelry brands, in March. Photo courtesy of the Monterrey, Mexico Chapter

	The actions of GIA alumni benefit countless others around the world. Each is a wonderful example of our alumni network and its members providing advice and guidance so others can progress in their careers and enhance their gem and jewelry knowledge.

	I see the value and scope of our alumni relationships in my daily work with members and chapters and also first-hand at the trade fairs I attend. I was fortunate to have the opportunity to connect with fellow alumni at the following shows so far this year:

Tucson Gem and Mineral Show: Tucson is a very important show for GIA and our alumni. The annual alumni dinner dance and reunion "Party at the GIA Gem Mine" is a favorite venue to reconnect and have fun together and an Alumni Chapter Leadership Forum meets to share ideas and issues that will benefit chapters. See more information on this year’s Party at the GIA Gem Mine – and images of alumni members celebrating together.

Baselworld: Glamour abounds at this fair, attracting global brands, suppliers and attendees to Basel, Switzerland. I was able to meet with alumni chapter representatives from Germany, Mumbai, Portugal and Switzerland!

AGS Conclave: This annual event hosted by the American Gem Society (AGS) brings together a vast array of its members (most are GIA alumni) from across the U.S. and Canada for a multi-day education conference. As in past years, many of our chapter leaders were in attendance.

	It’s exciting to see lifetime friends reconnect in person or new friendships form at these trade shows. Members offer mentorship and share knowledge and business relationships are established. It’s a constant reminder of how many individuals can trace their connections and colleagues to fellow GIA graduates.

	The GIA Alumni Association and its network offer a variety of opportunities and services for its members − all you have to do is be an active participant to benefit. GIA has participated in more than 25 trade fairs since the start of the year, reaching our industry constituents and alumni in Africa, Asia, Europe, Middle East and North America. If you aren’t a member already, stop by one of our booths to find out how to get involved.

	Stay connected. Stay informed.

	Taiwan chapter guest welcomes attendees to a year-end event. Photo courtesy of the Taiwan chapter

	Chapter Activities:

	A particularly beneficial way to build industry relationships is through GIA alumni chapter meetings and activities worldwide. Chapters have been busy hosting more than 50 education and networking events for their members since January.

		A meet-up at the Inhorgenta Fair in Munich was coordinated by Germany and attended by local and visiting alums.

		Film screenings related to the gem and jewelry industry were presented in Northeast and South Florida, Washington D.C. and Monterrey –  Mexico.

		Auctions, antique and ancient jewelry was the focus of talks in  North Carolina ,  Seattle  and Washington D.C.

		Year-end chapter celebrations were held in   Cincinnati  ,  Hong Kong  and Taiwan.

		Member socials were hosted by Metro-Phoenix, Ontario – Canada, Switzerland and by Texas’s Lone Star and  Houston clubs.

		Post-Tucson market reviews and show-and-tells were held in  Houston ,  North Carolina  and Washington D.C.

		Lapidary skills were shared by award-winning gemstone cutter and mineral trader Brett Kostnar, with guests of Colorado’s Mile High chapter.

		Mediterranean coral talks were presented by Andres Neves Bento, president of Spain’s chapter to the  Monterrey – Mexico  and Portugal chapters.

		Jewelry design, art jewelry and watch talks were held in   San Diego  ,  Manhattan  and Metro-Phoenix.

		CAD/CAM design and 3-D printing, gemological instrumentation and application were subjects of meetings for  Monterrey – Mexico  and Ontario – Canada.

		Hands-on study sessions and labs were held in  Manhattan  and Twin Cities – Minnesota.

		A museum tour featuring a Cartier exhibit and field trip to Macau’s jewelry pawn district were held for the  Switzerland  and Hong Kong members, respectively.

		Colored gemstone and subject matter experts are always eager to share their knowledge at chapter meetings. Jeff Mason, of Mason Kay, Inc. spoke on jade and the state of the marketplace at a   New England   chapter; Bruce Bridges, of Tsavorite USA, Inc., shared his lifetime experience of Tsavorite mining in Kenya at the  Golden Gate  chapter; and author Renee Newman presented exotic gems in St. Louis.

		Identification of synthetic gemstones and diamonds were presented by Antoinette Matlins and Danny Baruch to the  Golden Gate  and Manhattan chapters.

		GIA representatives including Andy Lucas, Shane McClure, Dr. James Shigley and Dr. Tao Hsu shared their expertise and provided updates in   Atlanta  ,  London , Hong Kong, San Di ego a nd  Los Angeles.

		New chapters were launched in   Vermont  ,  Portugal  and Tucson.

		New chapter leadership was elected in   Hong Kong  ,  London , Malaysia and Wash ington D.C.

 The North Carolina chapter held a post-Tucson market reviews and show-and-tell in March. Photo courtesy of the North Carolina chapter

 Looking Ahead

GIA Alumni Japan will celebrate its 25th anniversary on May 22 in Tokyo with a reception and presentation from GIA.

 JCK Las Vegas : Don’t miss GIA’s in-booth briefings, museum experience, hands-on seminars and alumni cabana at JCK Rocks the Beach. Learn more about GIA’s schedule of social and educational activities.

The Malaysia chapter invites all alumni to attend its second annual international conference in Sri Lanka in August. The chapter plans to coordinate education opportunities, visit gem markets and attend the 2016 Facets Jewelry Show. For further details please contact the chapter.

	The GIA Alumni Association offers students, graduates and members of the trade boundless opportunities to grow their knowledge, relationships and industry networking. I encourage all of you to consider getting more involved. @chapter:34


Publication Year: 2013 Title: A Large Irradiated Green-Yellow Diamond Abstract: Figure 1. This 24.16 ct oval-cut diamond (20.47 × 14.00 × 10.72 mm) was color graded as Fancy Intense green-yellow, and identified as artificially irradiated and annealed. Photo by Jian Xin (Jae) Liao.

		Artificially irradiated diamonds are common in the trade, and identifying them remains a challenge. The New York lab recently identified a large diamond as artificially irradiated based on careful spectroscopic analysis and a review of the lab’s database.

	This 24.16 ct oval-cut diamond (20.47 × 14.00 × 10.72 mm) was color graded as Fancy Intense green-yellow (figure 1). The color was distributed evenly throughout the stone, with no color zoning detected. It showed strong yellow and blue fluorescence to long-wave UV radiation, and moderate yellow fluorescence to short-wave UV radiation. This fluorescence reaction and absence of chalkiness are seen in some natural diamonds with a similar bodycolor. Absorption spectrum in the mid-infrared region showed saturated absorptions in the one-phonon region, indicating a type Ia diamond with a high concentration of nitrogen. Also recorded were a moderate platelet peak at 1368 cm–1 (approximately 2.1 cm–1 intensity) and a weak absorption at 1433 cm–1. No hydrogen-related absorption or H1b/H1c center in the near-infrared region was recorded. Absorption spectrum of this diamond in the ultraviolet/visible/near-infrared (UV-Vis-NIR) region at liquid-nitrogen temperature (figure 2) showed a moderately strong absorption from the N3 (415.2 nm) and H4 (496.0 nm) centers, as well as weak absorptions at 512.8, 594.4, and 741.2 nm (GR1).

		Figure 2. After irradiation and annealing treatment, a significant amount of optical center H4 was introduced. This is mainly responsible for the color improvement from Fancy brownish greenish yellow to Fancy Intense green-yellow. N3 absorptions in two spectra in this plot were normalized to the same intensity.

		Absence of the H3 optical center was confirmed by photoluminescence spectroscopy at liquid-nitrogen temperature with 488 nm laser excitation. A fluorescence image collected using the DiamondView showed a gradual change from a predominantly blue table region to a mostly green upper pavilion and girdle area. The spectral features observed in this large diamond are rarely encountered in natural diamonds, raising the possibility of artificial irradiation treatment.

		A search of the GIA database found a very good match between this stone and a previously tested diamond. The two diamonds were identical in measurements and weight, as well as their infrared absorption spectroscopic features, though the previous grade was Fancy brownish greenish yellow. This significant improvement in color appearance is attributed to the relatively high concentration of the H4 center produced by the artificial irradiation/annealing treatment confirmed in this study.

		Despite its suspicious spectroscopic features, this irradiated diamond showed some gemological features normally observed in diamonds with similar natural color. This example demonstrates the value of careful spectral and gemological analysis, combined with a review of the GIA database, in gem identification. @chapter:11


Publication Year: 2004 Title: The Creation of a Magnificent Suite of Peridot Jewelry: From the Himalayas to Fifth Avenue Abstract: A magnificent suite of peridot: The ultimate value of a gemstone suite lies not only in the cost and quality of the materials themselves, but also in the selection of the rough, the quality of the faceting, and the intricacy of the setting in a well-designed and well-manufactured suite of jewelry. This article chronicles the creation of a fine suite of peridot jewelry from the mine in the Himalayas to the manufacture of the necklace, bracelet, ring, and earrings. Eight kilograms (40,000 carats) of peridot rough from the Sapat Valley region of Pakistan was purchased in early 2004. Following the assessment of the rough, careful preforming and faceting produced a precisely matched suite of Asscher-cut peridots. The suite comprises 54 gems ranging from 3.57 to 18.30 ct, for a total weight of 350.40 ct. Van Cleef & Arpels in Paris designed the jewelry, and the New York atelier of Van Cleef & Arpels manufactured the five pieces. @chapter:25


Publication Year: 1981 Title: The Chromium Content of Lechleitner Synthetic Emerald Overgrowth Abstract: The refractive indices of the synthetic overgrowth on the beryl seeds of Lechleitner synthetic emeralds show a linear correlation with the chromium content of the coating. In a sample with refractive indices of no=1.580, ne=1.572a, Cr203, content of 3.99% was found; a stone with no=1.610, ne=1.601 contained 10.01 % Cr2O3. Very broad, faint shadow edges on the refractometer in one sample were caused by an inhomogeneous distribution of Cr2O3,--between 7.64% and 13.20%--in the synthetic emerald overgrowth. From these experiments, it is evident that the higher the chromium content in the overgrowth, the darker the coating (and, therefore, the overall appearance of the stone) will be. @chapter:9


Publication Year: - Title: Ruby Care and Cleaning Guide Abstract: Ruby is an incredibly durable gemstone if there are no treatment-related durability concerns. - Courtesy Jan Goodman Co.

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

Corundum (ruby and sapphire) is relatively hard—9 on the Mohs scale. It has excellent toughness and no cleavage, which is a tendency to break when struck. This makes it a great choice for rings and other mountings subject to daily wear.

	Ruby ranks 9 on the Mohs hardness scale, so it’s an effective jewelry stone.

Stability
Corundum is stable under normal wearing conditions, which means it’s resistant to the effects of heat, light, and common chemicals. Boric acid powder will etch the surface of even untreated stones. Fracture-filled, cavity-filled, and dyed stones can be damaged by even mild acids like lemon juice.

Cleaning
Warm soapy water is always safe. Ultrasonic and steam cleaners are usually safe for untreated, heat-treated, and lattice diffusion treated stones. Fracture-filled, cavity-filled, or dyed material should only be cleaned with a damp cloth.

Treatment and durability considerations
Untreated ruby and even heat-treated ruby are very durable. Stones that have undergone lattice diffusion treatment have varying degrees of treated-color penetration. In some stones, the treated color penetrates the entire stone, while others have very shallow treated-color penetration. For stones with shallow color penetration, surface damage or re-cutting can remove color.

Today’s fracture-filled stones have surface-reaching fractures filled primarily with a high-lead content glass. There are large numbers of these treated rubies in the market and they require greater care than untreated, heat-treated, or lattice diffusion treated ruby. The glass can be damaged through contact with a variety of chemicals. Even relatively mild substances like lemon juice can cause changes in the high-lead content glass. @chapter:23


Publication Year: 2003 Title: Pezzottaite from Ambatovita, Madagascar: A New Gem Mineral Abstract: Pezzottaite, ideally Cs(Be2Li)Al2Si6O18, is a new gem mineral that is the Cs,Li–rich member of the beryl group. It was discovered in November 2002 in a granitic pegmatite near Ambatovita in central Madagascar. Only a few dozen kilograms of gem rough were mined, and the deposit appears nearly exhausted. The limited number of transparent faceted stones and cat’s-eye cabochons that have been cut usually show a deep purplish pink color. Pezzottaite is distinguished from beryl by its higher refractive indices (typically no=1.615–1.619 and ne=1.607–1.610) and specific gravity values (typically 3.09–3.11). In addition, the new mineral’s infrared and Raman spectra, as well as its X-ray diffraction pattern, are distinctive, while the visible spectrum recorded with the spectrophotometer is similar to that of morganite. The color is probably caused by radiation-induced color centers involving Mn3+.

	DATA DEPOSITORY

Table 1: Electron-Microprobe Analyses of Pezzottaite Done at the University of New Orleans
Table 2: Mn, Fe, and Ti Abundances in Pezzottaite and Red and Pink Beryls
Spectra: IR Absorption, Raman, and X-ray Diffraction
	Submitted by Brendan M. Laurs
	January 20, 2004 @chapter:5


Publication Year: 2017 Title: The “Montana Queen” Sapphire Abstract: Figure 1. The 31.98 ct (6.40 g) rough sapphire crystal as it was mined. Photo by Jeffrey R. Hapeman.

In September 2016, while viewing a selection of large Montana sapphires mined by Potentate Mining at their new operation at Rock Creek, one stone stood out. It possessed a beautiful medium blue-green color and a hexagonal crystal form with a blue rim and golden center (figure 1). It weighed 31.98 ct (6.40 g) and appeared to be free of major internal defects. Sapphires this large make up less than 0.25% of Rock Creek’s production, and they are typically fractured or otherwise included.

Most Rock Creek sapphires have frosted or etched surfaces, apparently as a result of partial resorption in the host rock. To assess the quality of this sapphire before cutting, a window was polished, allowing a view of the interior of the crystal; this removed just over one carat, as a surface crack was also ground away. The window revealed that the center gold spot was composed of golden rutile needles that could be cleared by heating. A mostly rehealed parting plane and a few crystal inclusions were also visible. We decided to heat the stone to dissolve the silk, hoping that the parting plane and internal inclusions would not fracture during the process. The heating, performed by Dale Siegford (The Sapphire Gallery, Philipsburg, Montana), dissolved all the silk and changed the rough’s color to a deeper, more uniform blue (figure 2). Most importantly, none of the inclusions spread or formed larger fractures.

Figure 2. The rough sapphire after heating, with a window polished to view the interior. Photo by Jeffrey R. Hapeman.
While size is always a cutting consideration, color is also a determining factor in the value of the finished gemstone. The pleochroism of sapphire crystals means that orientation is critical for the best presentation of color. This sapphire had a rich blue c-axis just slightly tinted with green, while the a-b axis was a medium shade of green. Fortunately, the crystal was shaped such that the best orientation for both color and size were the same—the table could be positioned directly on the c-axis. Our goal was to feature the stone’s natural hexagonal shape, increasing yield and preserving the crystal’s beauty. GemCad and GemRay were used to work through a series of designs, optimizing them for a combination of light return and scintillation. The intent was to use facets large enough to create broad flashes of color while concealing the minor inclusions. With a gem this rare there is no room for error, so the final design was test-cut on a smaller Rock Creek sapphire to validate the modeling.

Once we were satisfied with the result on the test stone, the cutting of the large gem began on the pavilion. Because the natural shape of the gem matched the final outline, only minor preforming was required; the rough gem weighed 30.84 ct when attached to the dop. There was a crack near one side of the gem, so it was dopped slightly off-center to ensure it would be removed in the cutting process. The gem was faceted in three steps: The facets were cut with a 600-grit sintered lap, followed by a pre-polish with 8,000-mesh diamond and an ultrafine polish using 100,000-mesh polycrystalline synthetic diamond. After completing the pavilion, the gem was transferred to a new dop and the process was repeated to cut the crown (figure 3).

Figure 3. The sapphire during the cutting process. The polished pavilion is shown on the left and the rough-cut crown on the right. Photos by Jeffrey R. Hapeman.
The finished gem weighed 12.62 ct, for a yield of 39.5% from the original rough (figure 4). The authors are aware of only two larger faceted Montana sapphires, one with similar quality. Neither of those stones is blue—one is purple and the other green—making this perhaps the largest faceted blue Montana sapphire, slightly larger than the famed 12.58 ct Big Sky sapphire. Due to its size, rarity, and beauty, this gem was named the “Montana Queen.”

Figure 4. The finished 12.62 ct Montana Queen sapphire. Photo by Jeffrey R. Hapeman. @chapter:20


Publication Year: 2023 Title: CVD-Grown Diamond with Few Diagnostic Features Abstract: Figure 1. The PL spectra for a 1.40 ct CVD-grown diamond are shown in red. Left: The 514 nm PL spectrum reveals relatively weak NV centers and no detectable silicon. For comparison, the 514 nm PL spectrum for a more commonly observed as-grown CVD (purple) shows much stronger NV centers and detectable silicon. The Raman lines (not shown) are scaled as equal. Spectra are offset vertically for clarity. Right: Many locations on the CVD-grown diamond were analyzed with 457 and 633 nm excitation to verify whether the 468 nm center or the SiV– center could be detected; this very weak peak of the 468 nm center was only detected at the culet.
Diamonds grown by chemical vapor deposition (CVD) have evolved rapidly in the last two decades. However, the vast majority submitted to GIA for reports still show several diagnostic features such as the silicon vacancy or SiV– defect (a doublet at 736.6 and 736.9 nm) and/or the 468 nm peak when analyzed by photoluminescence (PL) spectroscopy. Additionally, most CVD diamonds have distinctive fluorescence images when analyzed by deep UV with the DiamondView instrument.

Figure 2. Left: The deep-UV (<230 nm) fluorescence image showed blue coloration (due to the presence of dislocation bundles) that appeared nominally similar to DiamondView images of natural type IIa diamonds. Right: When the fluorescence was filtered by an orange long-pass filter that blocked wavelengths below 550 nm, the NV-related fluorescence and the striations indicative of CVD growth became apparent. Image by Sally Eaton-Magaña (right).
Therefore, it was interesting to analyze a 1.40 ct E-color, VVS2 type IIa diamond submitted for a laboratory-grown diamond report. Initial PL data collection did not show either the SiV– center or the 468 nm peak. The features observed were a 3H peak at 503.5 nm using 455 nm excitation and relatively weak nitrogen vacancy (NV) centers at 575 (NV0) and 637 (NV–) nm using 514 nm excitation (figure 1, left). The stone showed weak anomalous birefringence indicating strain; while this observation is helpful in confirming whether a diamond is grown by high-temperature, high-pressure (HPHT) methods, such birefringence cannot distinguish between natural and CVD origins. The deep-UV fluorescence image showed only deep blue coloration, which appeared generally comparable with the vast majority of natural type IIa diamonds (figure 2, left). Therefore, many of the standard markers of CVD origin were not present even when examined using advanced methods. Careful analysis of the fluorescence image revealed some distinct differences from the majority of natural diamonds, namely the patchiness of the fluorescence with some inert regions.
Many models of the DiamondView instrument include a series of filters that permit fluorescence imaging in which portions of the visible spectrum are blocked out. Using these filters, the blue portion of the visible spectrum was blocked in order to observe weaker underlying fluorescence features. With the orange long-pass filter blocking wavelengths less than 550 nm, NV-related fluorescence clearly showed the striations indicative of CVD growth (figure 2, right). Also, several locations of the diamond were analyzed with PL spectroscopy to determine if either the 468 nm center or the SiV– could be detected. Only at the culet was a small 468 nm feature observed (figure 1, right).
The author concluded that this was a CVD-grown diamond with no evidence of post-growth treatment. This example is a noteworthy indicator that as CVD growth methods improve, telltale defects are being minimized or eliminated entirely. Careful examination of all data, both spectroscopic and fluorescence imaging, is needed to provide accurate origins for diamond. @chapter:15


Publication Year: - Title: Gem Mining in Cambodia Abstract: GIA’s field gemologist shows how sapphire, ruby, and other gems are mined in Pailin, a province in western Cambodia near the Thai border.

	River Mining in Pailin, Cambodia

	Sapphire and Ruby Mining @chapter:25


Publication Year: 1984 Title: Winter 1984 Gem News International Abstract: Diamonds
            Australia: Mining Magazine Reports Loan for Argyle Development
            India: Nearly 50 ct Golconda “D” Diamond Reappears
            Thailand: Noted Gemologist Sinkankas Reports on Alluvial Diamonds
            USA: Diamond Melts in Laboratory Accident at Cornell University
                     Punch-Jones Diamond Sold at Sotheby’s
                     World’s Largest Uncut Diamond (890 ct) On Display at Smithsonian
            USSR: Scientists at USSR Academy of Science Produce Synthetic Diamond
Colored Stones
            Yellow-Green Chrysoberyl Found in Queensland, Australia
            Sri Lanka Cancer Institute Uses X-ray Equipment to Irradiate Yellow Sapphires
            One of Largest, Finest Gem-Quality Opals Ever Discovered Found in Mexico
            Notes on Danburite, Zircon, and Andalusite Translated from Spanish Gemology Bulletin
            Treated Moroccan Anglesites
            Large, Very Fine Emerald Crystal Recently Discovered in North Carolina
Precious Metals
            Significant Gold and Ore Deposits Found in Alaska
            First Precious Metals Refinery in Asia outside Japan Opens in Singapore
            Sri Lankan Gold Jewelry to be Hallmarked
Synthetics
            Gem-Quality Synthetic Jadeite Created at G.E.
            Russian Hydrothermal Synthetic Emeralds
Announcements
            102-ct Light Yellow Ashberg Diamond Currently on Display in Los Angeles
            Tiffany Iris Corsage and Other Important Jewelry in Traveling Exhibition
            Tucson Gem and Mineral Society’s 31st Annual Show Set for Tucson
            Third Annual Meeting of the Association of Women Gemologists
            ICA to Sponsor a Colored Gemstone Congress in Idar-Oberstein
            22nd Burma Gem, Jade and Pearl Emporium Will Be Held in February 1985
            Australian Jewelry Fair Will Be Held in Sydney February 16-20, 1985
            Dates Announced for 1985 Basel Fair, Switzerland

To view the full section, download the PDF above. @chapter:24


Publication Year: 2005 Title: Winter 2005 Gem News International Abstract: Colored Stones and Organic Materials
            Ornamental Blueschist from Northern Italy
            Emerald Phantom Crystal
            Unusual Trapiche Emerald Earrings
            A Large Greenish Yellow Grossular from Africa
            An Opal Triplet Resembling an Eye
            Green Orthoclase Feldspar from Vietnam
            New Discoveries of Painite in Myanmar (Burma)
            Gem Plagioclase Reportedly from Tibet
            Spinel from Southern China
            Update on Tourmaline from Mt. Mica, Maine
Synthetics and Simulants
            Lizard in Amber?
            Cubic Zirconia as Rough Sapphire Imitation
            Barium-Rich Glass Sold as Diamond Rough
            “Color-Change” Glass Update
Conference Reports
            Diamond 2005
            Geological Society of America 2005
            World Diamond Conference, Perth, Australia
Exhibits
            Pearl Exhibit in Tokyo
            Cameos at the Met
            King Tut Returns

To view the full section, download the PDF above. @chapter:2


Publication Year: - Title: Diamond Producers Aim for Lower Qualities in Today’s Market Abstract: An array of diamonds of various sizes and qualities at Alrosa’s sorting operation in Arkhangelsk. Sizes and qualities of diamonds are distributed unevenly throughout kimberlite pipes and mining companies have learned to tailor their products according to market conditions. Photo by Russell Shor/GIA

The average value of rough diamonds mined last year took a sharp drop according to the latest Kimberley Process (KP) data.

The KP reports that world diamond production was 134 million carats, which was valued at $12.4 billion in 2016, or just under $92.50 per carat. That is in comparison to 127 million carats valued at $13.9 billion, at $109 per carat, in 2015.

Examining the figures more closely, some of the biggest drops in value came from countries where diamond mining is in the hands of the major, sophisticated operations of De Beers, Rio Tinto and Alrosa, in South Africa, Canada and Russia, respectively.

At the same time, diamond demand in major consumer markets, such as the U.S., China and Japan, has trended toward smaller stones and lower qualities.

This isn’t exactly a coincidence.

The major mining companies like to say they dig and sell whatever nature gives them, but technology has given them a way to tweak nature’s generosity. Information tucked into the annual reports of the major mining companies (De Beers, Alrosa and Rio Tinto) shows that they are doing just that – and concentrating their mining on lower quality areas.

Diamonds are not spread evenly inside even the richest grade kimberlite. In some sections, there may be three carats of rough for every ton of kimberlite mined and crushed. In others, there may be only a half carat. It’s the same with size and quality: one section may yield a high percentage of larger higher quality rough, while other parts of the kimberlite may be sprinkled with a concentration of smaller goods and lower qualities.

Thanks to highly sophisticated computer modeling technology, geologists at diamond mining sites can better pinpoint specific areas by continually taking core samples using the data to model the diamond distribution within the kimberlite pipe and adjust their production accordingly. The makes it possible for the diamond miners to be more profitable. They can keep production going at the most efficient levels, with less stockpiling of goods for which there is slow demand.

A geologist examines core samples extracted from approximately 250 feet within Alrosa’s Arkhangelsk kimberlite pipe. Diamond mining companies take many such samples to determine how the diamonds are distributed within the pipe. Photo by Russell Shor/GIA
Interviews at trade shows – Baselworld and Las Vegas this year and Hong Kong late last year – revealed a definite shift in demand toward smaller diamonds and lower qualities. China, for example, which had not favored SI and I1 clarities, began to embrace them as consumers sought to keep expenses down. Indeed, a recent study by the marketing research firm McKinsey & Co., found that luxury buyers in China have become much more price sensitive and much more knowledgeable in the past few years.

Comparing the two years shows that 2015 was a difficult period for the diamond industry and that rough prices fell by an average of 15% during the first half of 2016. Average production value in Canada and South Africa fell nearly 25% – Canada from $143.52 to $107.18 and South Africa from $192.57 to $150. Russia’s average value fell in accordance with the market, from $101 to $88.7, but officials announced earlier this year that they had begun to concentrate production and sales in lower qualities.

The fall in the average price of Botswana’s diamonds (from $143.73 to $138) was much smaller, mostly likely because of the nation’s dependence on diamond revenues and the huge sway it has over De Beers (it holds a 15% stake) and the fact that De Beers’ largest, cheapest-to-run diamond mines are within its borders.

Diamonds continue to flow from Zimbabwe, but at a much lower rate. Production of just two million carats in 2016 was less than half of 2015, though its $50 per carat value remained unchanged and has so for several years.

The reason for this precipitous drop is that the country’s government expelled four of the six mining companies operating the large Marange deposit after they refused to merge their operations into the state diamond company, Zimbabwe Consolidated Diamond Corp. The government’s offer was a combined 50% stake in the company with shares apportioned to the size of their assets.

The companies refused on the grounds that the shallower areas of the Marange deposit have been depleted and that they would have to bear all of the high investment costs of redeveloping the deposit into deep mining operations, even as yield declines.

Five years ago, the country’s diamond production topped 12 million carats with predictions that it could top 20 million within a few years, but as mining grew more difficult and costly, production fell to just under five million carats, prompting the government, which depends on diamonds for 30% of its revenues, to blame mining companies for the production fall off.

A close up view of piles of diamond rough show how the different colors are sorted. Photo by Russell Shor/GIA
Analyst Edahn Golan recently pointed out the huge rise in production from Democratic Republic of the Congo, from 14.7 million carats to 23.7 million, but that the aggregate value only increased by 7%. He theorizes that the Congo, whose production comes from extensive alluvial diggings as well as a state-run mine, miscounted its production figures.

On the export side, there was very little change, with just under 95% of the rough going to five destinations: 39% to India, 30% to EU/Antwerp, 18% to UAE/Dubai, 4% to Israel and 4% to China. Dubai and Antwerp are transfer centers where mining companies have their sales offices, while China remains the destination for much Zimbabwe rough. This will surely show a decline when the 2017 figures are released next summer. @chapter:38


Publication Year: - Title: The Latest in Field Gemology from Wim Vertriest: Sapphires and Demantoid Garnets from Northern Madagascar Abstract: Demantoid garnet rough mined from northern Madagascar. Photo: Wim Vertriest/GIA.
On January 24th 2024, Wim Vertriest, GIA Manager of Field Gemology, gave GIA’s first student lecture of the year at the GIA World Headquarters in Carlsbad, California. In this lecture, Wim explored the purpose of GIA field gemology and dove into the wealth of gems and minerals that can be discovered in Madagascar — particularly those in the northern parts of the country. Join us as we cover some of the highlights of this riveting topic or watch the full lecture on Facebook.
The Purpose of GIA Field Gemology
When GIA researchers go on field gemology trips, they have two primary goals — acquire gemstones for treatment and country of origin research and learn about the story and context surrounding gemstones.

A gem’s story includes its geology, mining methods and environmental impact, as well as the culture, history, politics, and miners involved in mining gems from different sources. Understanding a gem’s context from multiple perspectives helps the trade and the public better appreciate the gem’s value and significance.

GIA researchers Aaron Palke and Wim Vertriest at miner's home in Madagascar. Photo: Kevin Schumacher/GIA.
Madagascar: Unparalleled Diversity of Gemstones
Madagascar has long been known for its incredible wealth and diversity of minerals and gemstones. There are over three hundred and eighty-nine known minerals in Madagascar, roughly eighty of them occurring in gem quality. Eighteen of these gems and minerals, including liddicoatite, pezzottaite, and dumortierite, were first discovered in Madagascar.

Classic gems mined in Madagascar include beryl, tourmaline, and quartz. Sapphires, first discovered there in the early 1990s, are considered a recent discovery.

The most important sapphire deposits in Antsiranana Province, at the northern tip of Madagascar, are located in the Ambondromifehy region in and near the Ankarana Special Reserve. The inset shows the location of the three major sapphire deposits in Madagascar: Ambondromifehy, Andranondambo, and Ilakaka.
The Formation of Madagascar Sapphires
The geology of Madagascar is largely dominated by events that took place roughly half a billion years ago when several continents smashed together to form the Gondwana supercontinent. This collision created the East African orogeny, a vast mountain range where many gems formed. The gems that formed along the roots of this mountain range include rubies and sapphires from Central & Southern Madagascar, Sri Lanka, and Tanzania; rubies from Kenya and Mozambique; emeralds from Ethiopia; and Cuprian tourmalines from Mozambique. This explains the wealth and similarities of gems found all throughout East Africa and on the island of Sri Lanka.

The Northern part of Madagascar has a different geological history. This area is dominated by much younger volcanic intrusions that resulted in many exotic mineralizations, including sapphires related to a specific type of magma that geologists call alkali-basalt.

Sapphire miners in Madagascar. Photo: Wim Vertriest/GIA.
Magmatic/Basaltic Sapphires vs. Metamorphic Sapphires
Madagascar can be roughly divided into three geological regions — mountains related to volcanoes in the north, highlands that are the remnants of an ancient mountain range (consisting of high-grade metamorphic and magmatic rocks) in the center, and flat plains along its west coast that consist mostly of sedimentary rocks.

Sapphires found in the north are magmatic or basaltic, meaning they formed deep within the earth and were brought to the surface by volcanic activities, hitching a ride from alkali basalt magma as it pushed up through the earth. Basaltic sapphires, such as those from Diego-Suarez, tend to be blue, green or rich yellow in color, sometimes combining more than one color in the same stone. Sapphires in the south, including those found at the vast deposit in the grassy plains around Ilakaka, are metamorphic sapphires. They tend to come in a different range of color, including pale yellows, pinks, and some blues.

Some gemologists call Madagascar sapphires “jungle sapphires” because they are mined in the jungles of Madagascar, often by farmers who grow pepper, cocoa and vanilla. These farmers turn to mining during off seasons to earn supplemental income. Mining is only seen as a secondary source of income for farmers, because finding foreign purchasers for mined goods can be a challenge.
Malagasy Demantoid Garnets, sometimes referred to as “Mangrove Garnets”
Demantoid andradite garnets, which are known for their lush green color and incredible fire and brilliance, are among the most valuable garnets on the market, sometimes fetching up to US$10,000 a carat. Demantoids tend to come in small sizes, with stones over one carat being incredibly rare, and stones over three carats being virtually unheard of. Madagascar demantoids are found in mangroves, and the easiest way to access the mine is by boat. During high tide, the entire forest is flooded, and gemologists must rely on experienced boat guides to find the mine.

Miners recover Madagascar demantoids from skarn, a coarse-grained metamorphic rock. Skarns are formed when mineral-rich fluids intrude into layers of sedimentary rocks/layers that mainly consists of clay, sand, or limestone. While these fluids move through the sedimentary rocks, they react with each other forming a whole new suite of minerals. The final result is a skarn, where many exciting and exotic crystals like demantoid can form.

Demantoid mine in the mangrove forests of Madagascar. Photo: Wim Vertriest/GIA.
Mining Demantoids
Due to the tropical climate in Madagascar, the weathering of rocks has been very intense. Demantoid host rocks are often called “rotten” due to the strong alteration. This makes mining easier since the crews don’t need explosives to break them up. Instead, miners use excavators and jackhammers to remove unwanted rock. Once miners see an indication that a demantoid-rich pocket is near, they resort to hand tools to avoid damaging the crystals. Demantoid-rich pockets can range from football-sized up to the size of a classroom, producing up to several kilograms of material each. The most sought-after demantoids are a rich jungle green or a fresh minty green in color with strong fire. Gems with brown or yellow tones are less desirable.

Demantoids were first discovered in Russia, which is a classic source for demantoids that are rich and vibrant in color and sometimes contain horsetail inclusions. Demantoids in African countries, including those from Madagascar, never have horsetail inclusions and are often less saturated in color. This can be an advantage, however, if you value fire over color, as lighter color allows more fire to shine through.

This faceted demantoid (7.17 ct) is representative of the finest material from Antetezambato. Photo: Matteo Chinellato.
Knowing the geology, history, mining, and environmental impact of gems empowers consumers to make informed choices and to better appreciate the journey their stones took to reach their jewelry boxes. It also empowers those in the gem and jewelry trade to make decisions that ensure the well-being of the parties involved in a gemstone’s mine-to-market journey.

Want to catch the next exciting student lecture? Connect with us on Facebook to stay up to date on upcoming events, GIA’s latest course offerings, and more. @chapter:37


Publication Year: 1998 Title: Natural and Synthetic Rubies on the Basis of Trace-Element Chemistry Abstract: Natural and synthetic gem rubies can be separated on the basis of their trace-element chemistry as determined by energy-dispersive X-ray fluorescence (EDXRF) spectrometry. This method is especially important for rubies that do not have diagnostic inclusions or growth features, since such stones are difficult to identify using traditional gem testing methods. The results of this study indicate that the presence of nickel, molybdenum, lanthanum, tungsten, platinum, lead, or bismuth proves synthetic origin, but these elements were not detectable in most of the synthetic rubies tested. Alternatively, the concentrations of titanium, vanadium, iron, and gallium––considered together, as a trace-element “signature”––provide a means for separating nearly all synthetic from natural rubies. EDXRF can also help identify the geologic environment in which a ruby formed, and thus imply a geographic origin. @chapter:6


Publication Year: 1992 Title: Fall 1992 Gem News International Abstract: Diamonds
            New Treatment Plant at Alexander Bay
            Results of Canadian Bulk Sampling
            British Crown Jewels to Move in 1994
            India Plans Increased Mining
            Expansion at Jwaneng
            Diamonds from Myanmar
            Venetia Mine Officially Opens
            Diamond-Cutting Plant in Vietnam
Colored Stones
            Amber with Insect "Inclusion"
            More Amber from Russia
            Blue Chalcedony from Montana
            An Unusual Zoned Specimen
            Diopside from Tanzania
            Ironstone Matrix as a Carving Material
            Mansfieldite Gemstone Egg
            Pearls from Baja California
            Natural Pearls from the New World
            Large South Seas Pearl Illustrated
            Pearl Culturing in Venezuela
            Faceted Ruby from Longido, Tanzania
            Sapphires from Madagascar
            Pennsylvania Sphalerite
            Tourmaline with Distinctive Inclusions
Enhancements
            Diffusion-Treated Sapphire Cabochons Sold as Natural
            Kit with Colored Fracture Filler
            Update on Dyed Green Quartz
            New Ruby Treatment
Synthetics and Simulants
            New Synthetic Alexandrite
            Glass from Mount Saint Helens Rock
            Unusual Assembled Glass Imitation
            Another Assembled Imitation Crystal Opal
            Natural-Appearing Synthetic Rubies on the Thai-Myanmar Border
            A New Twist to Imitations of Vietnamese Ruby
            Assembled Imitation Bicolored Tourmaline
In Memoriam
            Mr. Vahan Djevahirdjian of Hrand Djevahirdjian S.A.

To view the full section, download the PDF above. @chapter:20


Publication Year: 2018 Title: Coated Pink Synthetic Moissanite Abstract: Figure 1. This 0.41 ct pink stone was revealed to be a coated synthetic moissanite. Photo by Aurélien Delaunay.

The French Gemmological Laboratory (LFG) recently received a 0.41 ct pink stone resembling a pink diamond (figure 1) for identification. The surface of the stone showed numerous patches (figure 2), casting doubts about the natural origin of its color.

Figure 2. Metallic flakes on the surface raised questions about the origin of the pink color. Photomicrograph by Aurélien Delaunay; field of view approximately 1.8 mm.

Figure 3. Doubling of the edges, observed near the crown in this synthetic moissanite. Photomicrograph by Aurélien Delaunay; field of view approximately 3.4 mm.
Under the microscope, these flakes showed metallic luster. Furthermore, the pink color appeared concentrated at the surface. Some unevenness in the color was observed due to scratches of this film. When observed through the crown, the gem showed a clear doubling of its edges, indicating an anisotropic material. These observations confirmed the client’s doubts that the gem was a pink diamond (figure 3).
The sample was analyzed using infrared, UV-visible, and Raman spectrometers. All the spectra collected indicated a synthetic moissanite coated with a colored film. Chemical study of this film acquired with an EDXRF spectrometer revealed that iron and titanium were responsible for the color of the calcium-rich film.
This is the first example the LFG has seen of synthetic moissanite coated with a thin colored film. This type of treatment is not rare with topaz, quartz, diamond, or tanzanite. Gemologists must remain vigilant because this treatment can be performed on all gems, natural or synthetic. @chapter:17


Publication Year: 2024 Title: Unusual Aquamarine–White Beryl Abstract: Figure 1. A 41.51 ct freeform faceted bicolor beryl. Photo by Marina Boncompagne.
Recently, the author analyzed an interesting 41.51 ct faceted bicolor beryl (figure 1) composed of aquamarine and opaque white beryl. This gem belongs to Brazilian gem dealer Veber Leite and is part of his collection containing several similar specimens. According to Leite, the bicolor beryls were mined in Brumado, a city located in the state of Bahia, Brazil, but their geographic origin could not be confirmed.
Standard gemological testing of both sections revealed a specific gravity of 2.70 and a refractive index of 1.581–1.592. Ultraviolet/visible/near-infrared (UV-Vis-NIR) spectra revealed an absorption band centered at about 810 nm, also present in both sections. In beryl, this band is associated with Fe2+ (D.L. Wood and K. Nassau, “The characterization of beryl and emerald by visible and infrared absorption spectroscopy,” American Mineralogist, Vol. 53, No. 5, 1968, pp. 777–800; Y. Hu and R. Lu, “Color characteristics of blue to yellow beryl from multiple origins,” Spring 2020 G&G, pp. 54–65) and possibly enhanced by neighboring Fe3+ (S. Saeseaw et al., “Geographic origin determination of emerald,” Winter 2019 G&G, pp. 614–646). The blue section exhibited an anisotropic band around 600 nm when viewing an e-ray oriented absorption spectrum, typical of aquamarine (Hu and Lu, 2020). The white color was caused by an isotropic absorption band ranging from 400 to 700 nm with a nearly identical absorption coefficient through all wavelengths.
Although seemingly opaque, when exposed to the polariscope’s intense light source, the white portion allowed the passage of light and showed no extinction under crossed polarizers, suggesting a polycrystalline composition.

Figure 2. The Raman spectra of the blue and white sections in the 41.51 ct bicolor beryl. Spectra are offset vertically for clarity.
Raman spectra were collected at room temperature using a Horiba Scientific LabRAM HR Evolution spectrometer coupled with an Olympus Scientific Solutions BX-41 microscope with a 50× magnification lens. The acquisition time was 120 seconds, grating: 500 nm. For this analysis, a 532 nm excitation laser was selected. Both sections exhibited major peaks around 321, 395, 520, 683, 1011, and 1066 cm–1 (figure 2). Minor peaks were observed at 448, 622, and 1141 cm–1. The spectra were compatible with beryl and, although clarity treatment was not observed, displayed relatively strong absorptions at approximately 1504 and 1567 cm–1 (again, see figure 2) that may suggest the presence of a filling agent (M.L. Johnson et al., “On the identification of various emerald filling substances,” Summer 1999 G&G, pp. 82–107). Additional Raman analysis with a spectral range of 100–3500 cm–1 is required to determine whether the peaks are indeed related to a filling substance.

Figure 3. Left: The aquamarine−white beryl boundary. Right: Beryl channels parallel to aquamarine’s c-axis in the blue portion of the bicolor beryl. Photomicrographs by Marina Boncompagne; field of view 10.00 mm.
Microscopic analysis revealed a well-defined aquamarine–white beryl boundary (figure 3, left). Channels parallel to the c-axis were also observed (figure 3, right).
The author is aware of similar aquamarine−white bicolor beryl from the state of Minas Gerais, but this was the author’s first encounter with such beryl reportedly from Brumado, Bahia. @chapter:9


Publication Year: 2023 Title: Summary of the U.S. Jewelry and Gemstone Market in October 2023 Abstract: Market Value of Jewelry in the United States:
The market value of jewelry in the United States varies according to the data collection methods of each organization. In summary, the market value of jewelry in the United States ranges from approximately 60 to 70 billion USD, which is about 20% of the global market value. The United States ranks as the second largest jewelry market globally, following China and ahead of India, Hong Kong, and Japan, which rank 3rd, 4th, and 5th respectively in global rankings. Estimates indicate that 14.2% of the global jewelry market value is attributed to the United States, and 38.18% of global online jewelry trade is represented by the United States.
Jewelry Market in the United States in 2023:
In the second quarter of 2023, several major jewelry retailers in the United States reported a decrease in sales compared to the same period in the previous year, ranging from 5% to 12%. It is anticipated that the growth of the jewelry market in the United States will begin to slow down towards the end of 2023.
Consumer Spending on Jewelry in the United States:
In 2021, Americans spent an average of approximately $136.33 per person per year on jewelry, while U.S. households spent an average of $434.3 per household per year on jewelry. According to estimates by the Bureau of Economic Analysis (BEA) of the U.S. Department of Commerce, the estimated value of American consumer spending on jewelry in 2022 was $94.38 billion, an increase of 2.81% from 2021. Retail prices for jewelry have increased at an average inflation rate of 2% per year.
Key Trade and Consumption Areas in the United States:
California has approximately 6,486 jewelry businesses. The Los Angeles Jewelry District is the largest jewelry district in the United States, with nearly five thousand jewelry businesses, primarily wholesale. It is also one of the largest diamond trading centers in the United States, often referred to as the Los Angeles Diamond District.
Important Times for Jewelry Trade in the United States:
The peak period for general jewelry trade in the United States is during the holiday season, from November to December. The next busiest period is around Valentine's Day and Mother's Day. For wedding-related jewelry, the peak season is generally from June to August, preceding the period when Americans typically hold weddings, from September to November.
Consumer Profiles for Jewelry in the United States:
According to the latest data from Zippia in 2021:
50.5% of jewelry consumers are female, with the remaining being male.
The majority are White Americans (62.8%), followed by Hispanic and Latino Americans (14.5%) and Asian Americans (11.7%).
The average age is approximately 46 years old. Millennials, on average, spend about $203 per year on jewelry, higher than the overall American average of $157.9 per year.
Other Significant Jewelry Trade Areas in the United States:
New York has approximately 5,444 jewelry businesses, with jewelry districts and diamond districts being the largest trading centers in the world and the United States.
Florida has approximately 4,671 jewelry businesses, with over 400 retail stores in its Jewelry District.
Distribution Channels for Jewelry in the United States:
Most jewelry retail outlets in the United States are specialty stores or brand-focused retail stores. The number of retail jewelry outlets in the United States has shown a continuous decline since 2018, at a rate of approximately 2.4% per year. It is estimated that there were between 45,792 and 61,892 retail jewelry businesses in the United States in 2023, a decrease from 2022 ranging from 2.1% to 2.4%.
Key Jewelry Trade Shows in the United States:
Tucson Gem & Jewelry Show, www.jogsshow.com: Held at the Tucson Expo Center, Tucson, Arizona, this show is a wholesale event open to general consumers for viewing and purchasing. Next scheduled events:
Tucson Winter Gem & Jewelry Show: January 24 - February 4, 2024
Tucson Fall Gem & Jewelry Show: August 29 - September 14, 2024
Jewelry Circular Keystone (JCK) Las Vegas, https://lasvegas.jckonline.com: A jewelry trade show for industry professionals held at The Venetian Expo, Las Vegas, Nevada. Next scheduled event: May 31 - June 3, 2024
International Trade of Jewelry from the United States:
The total import value in 2022 was approximately $98 billion USD, a decrease of 0.23% from 2021. During the first eight months of 2023, the import value was approximately $63 billion USD, a decrease of 7.14% from the same period in 2022.
Imports of jewelry and precious stones in 2022 were approximately $2 billion USD, growing by 16.96%. During the first eight months of 2023, imports from Thailand were $1.1 billion USD, a decrease of 11.58%. Key imported products from Thailand to the United States in 2022 and 2023, ranked by import value (USD million), show that the import of precious stones used in jewelry manufacturing has grown more than the import of finished jewelry. @chapter:27


Publication Year: 2019 Title: Natural Sapphire with Trapiche Pattern Inclusions Abstract: The regular hexagonal inclusions consisted of six independent units, resembling a trapiche pattern. Photomicrograph and illustration by Yizhi Zhao; field of view 1.70 mm.
A blue gemstone pendant was recently submitted to Guild Gem Laboratories for identification. Standard gemological testing identified it as a sapphire, with a refractive index of 1.762–1.770 and birefringence of 0.008. Fourier-transform infrared (FTIR) spectroscopy combined with microscopic observation confirmed it was a natural sapphire. The UV-Vis spectrum indicated a basalt-related origin owing to relatively high iron content. The FTIR transmitted spectrum also revealed a 3309 series with peaks at 3366, 3309, 3232, and 3185 cm–1, which are commonly seen in basalt-related sapphire.
Microscopic observation showed several colorless crystals and fluid inclusions under reflective and transmitted light. Using a fiber-optic light, we also observed very interesting scenes of whitish clouds (see above) consisting of arrays of hexagonal particles. These particles seemed to be flat and parallel to each other. A distinct uniaxial interference pattern was observed when viewing perpendicular to these particles under the polariscope equipped with a conoscope, which proved that they were parallel to the basal plane (0001) crystalline face of corundum. Further observations revealed that each particle possessed six nearly identical triangular sectors, divided by six arms with hexagonal symmetry. Based on our microscopic observation and estimation, the diameters of the hexagons ranged from approximately 0.06 to 0.13 mm. This pattern was very similar to the trapiche structure seen in some sapphire, ruby, and emerald.
The depth of the inclusions prohibited Raman spectroscopy testing, but we will monitor this phenomenon in other samples for further study in the future. @chapter:12


Publication Year: - Title: Opal Care and Cleaning Guide Abstract: Opal can range from 5 to 6.5 on the Mohs hardness scale.

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

Opal hardness is variable depending on its exact composition and formation conditions, and ranges from 5 to 6.5 on the Mohs scale. Its toughness is very poor to fair, making opal a gem that is suitable for jewelry but requires care when wearing so as to not scratch or break the stone.

Stability
Opal is generally stable, but heat from intense light can cause fracture lines called “crazing.” High heat or sudden temperature changes can also cause opal to fracture.  Opal is attacked by hydrofluoric acid and caustic alkaline solutions.

Treatments
Opals can be treated by impregnation with oil, wax, or plastic, and by surface modifications called sugar treatment and smoke treatment.

Cleaning
The only safe way to clean opal is with warm, soapy water.

	With proper care, opal jewelry will provide years of enjoyment. - Courtesy Cody Opal @chapter:39