# Publication Year: -
# Title: Silver Sizzles
# Abstract: Cuff bracelets image courtesy of Kara Ross.

                      Sales of silver are sizzling. Some 91% of the jewelry retailers said sales of silver jewelry increased from 2011 to 2012, according to the National Jeweler/Nielsen silver survey. The average increase was 19%.

One reason sales are rising is that the metal is catching the eyes of men, according to the November 2012 issue of JCK. They have a growing appetite for silver cuff links, money clips, and dog tags. It’s also more affordable than gold and platinum, which also appeals to consumers.

But it’s not just trendiness and affordability that’s driving silver’s popularity. As one of the three Noble Metals (gold and platinum being the other two) silver has prestige. It’s also the whitest and brightest of all metals, giving it unmatched luster.

Metalsmiths like silver because it has excellent working characteristics: it’s pliable, readily bends into new shapes, and stays in that position. It’s also extremely strong and can withstand the knocks and bangs that come with frequent wear.

There’s also another side to silver’s renewed popularity. “Traditional and commemorative high-end gifts like baby rattles, teething rings, and picture frames are making a comeback. These items are typically made from silver, and this has created a renaissance for the metal,” says Mark Maxwell, manager of Jewelry Manufacturing Arts, GIA, Carlsbad.

The majority of silver is mined in Mexico, Peru, China, and Chile. In order to be called “silver” in the U.S., alloys must contain at least 92.5% pure silver. Copper is usually the other alloy.

Contemporary designers like David Yurman and Michael Good continue to experiment with the metal, creating new and edgy designs. So while silver has a storied provenance – it’s the stuff of Peruvian crowns and Edwardian tiaras – it’s still very much a modern metal.

	Cartier cufflinks courtesy of C. Danforth.
Tips on Silver

		Manufacturers are creating new silver alloys. Argentum, for example, does not oxidize.

		Let your customers know that silver has cachet. It was more valuable than platinum during the Victorian era, and it was the metal of choice for making tiaras for the aristocracy.

		Sterling silver is increasingly being used in jewelry. Manufacturers are setting diamonds and other stones in a variety of modern sterling silver alloys, and are offering a range of products that are more affordable. Lines of sterling jewelry with karat gold accents are doing well, especially because gold and platinum are at an all-time high. @chapter:45 @chapter:2 @chapter:45


# Publication Year: 1990
# Title: Jadeite of Guatemala: A Contemporary View
# Abstract: Although lost for literally hundreds of years after the Spanish conquest of the Aztecs, many deposits of jadeite have been found in Guatemala during the last two decades. Following the discovery of the first significant outcrop in 1974, literally tons of jadeite in a wide variety of colors have been removed from the area and sent to cutting shops for use in tourist carvings, in fine reproductions of Indian artifacts, and in jewelry. @chapter:51 @chapter:4 @chapter:51


# Publication Year: 2004
# Title: X-Ray Fingerprinting Routine for Cut Diamonds
# Abstract: X-ray topography is a nondestructive technique that permits the visualization of internal defects in the crystal lattice of a gemstone, especially diamond, which is highly transparent to X-rays. This technique yields a unique “fingerprint” that is not altered by gem cutting or treatments such as irradiation and annealing. Although previously a complicated and time-consuming procedure, this article presents a simplified X-ray topographic routine to fingerprint faceted diamonds. Using the table facet as a point of reference, the sample is crystallographically oriented in a unique and reproducible way in front of the X-ray source so that only one topograph is necessary for fingerprinting. Should the diamond be retrieved after loss or theft, even after recutting or exposure to some forms of treatment, another topograph generated with the same routine could be used to confirm its identity unequivocally. @chapter:36 @chapter:1 @chapter:36


# Publication Year: 2017
# Title: Sapphires from Northern Ethiopia
# Abstract: Figure 1. Rough sapphires from a new deposit near Chila, Ethiopia. Photo by Simon Bruce-Lockhart.

Since February 2017, rumors of a newly discovered sapphire deposit in northern Ethiopia have been circulating in the trade. In June, one of the authors (SB-L) visited the mining area, located in the country’s Tigray region. The city of Aksum (or Axum), about 35 km south of the Eritrean border, is used as a base for gem merchants. Mining and trading is concentrated around the town of Chila, about 25 km northwest of Aksum. Based on the literature, the alkali basalt field that produces the sapphire stretches into Eritrea, although no sapphires from that area have reached the market. Several sites are active, and about 5,000 miners were working the deposits. All of the deposits are secondary in nature and have yielded rounded crystals. The majority of the rough (figure 1) weighs 2–3 grams, but crystals over 50 g have been reported; the larger ones are usually cracked. Heat treatment experiments are being conducted in Chanthaburi (Thailand) and Beruwala (Sri Lanka) to see how the material reacts. It is estimated that 5–10% of the sapphires do not require heat treatment.

At the end of April, the first parcels started to arrive in Bangkok, and GIA was able to study selected samples donated by author SB-L. The color of the crystals ranged from dark to light blue, and many contained fine rutile particles. Some stones had a trapiche-like pattern. The stones occasionally exhibited a green or yellow color, sometimes combined with blue in bicolor sapphires. All of the sapphires studied by GIA showed strong blue-green pleochroism. The main inclusions were intersecting twinning planes (figure 2), along with crystals, fingerprints, tubules, and bands of rutile particles (figure 3).

Figure 2. An Ethiopian sapphire wafer with two polished windows perpendicular to the c-axis under crossed polarizers shows two sets of twinning planes. Photo by Victoria Raynaud; field of view 13.4 mm.

Figure 3. Left: An unidentified crystal surrounded by a fingerprint. Many particles and fine wispy fingerprints can be seen throughout the stone in darkfield lighting. Center: Intersection tubules associated with different types of fingerprints, shown here in fiber-optic lighting, were always found in the twinning planes of the Ethiopian sapphires. Right: Bands of particles seen with fiber-optic lighting. Photomicrographs by Victoria Raynaud; fields of view 1.20 mm (left), 3.60 mm (center), and 1.44 mm (right).
TKTrace-element analysis using laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) was performed on two samples. On each stone we measured 12 spots: six in a clean area and six in a particle-rich area. The clean areas from both stones showed very similar chemical composition, and the same was observed for the particle-rich areas. The compositional ranges of both stones, presented in table 1, clearly show that the chemical concentrations are different between the clean and particle- rich areas. None of the areas contained enough natural Be or Cr to detect with LA-ICP-MS. All samples showed a high Fe concentration. While Ti content was higher than Mg concentration in both areas, the particle-rich areas showed elevated levels of titanium (table 1). The UV-Vis-NIR spectrum shows a broadband around 860 nm, which is typical of basalt-related sapphires (figure 4).

TABLE 1. Chemical composition (ppma) of Ethiopiansapphire, obtained by LA-ICP-MSa.

24Mg
47Ti
51V
57Fe
69Ga

Clean area
8–9
10–12
0.7–1.0
1362–1450
58–66

Particle-rich area
11–14
15–43
0.6–0.8
1365–1588
57–64

aIn total, 12 spots in clean areas and 12 in particle-rich areas were analyzed. Be and Cr were both below detection limit (0.2 and 0.4 ppma, respectively).

Figure 4. UV-Vis-NIR spectrum of the o-ray of a greenish blue Ethiopian sapphire.
Optical path length 1.13 mm.
Starting in May, many Sri Lankan dealers have traveled to Ethiopia to buy this material, causing steep price increases in local gem markets. All of the mining around Chila is artisanal, but large volumes of sapphire have been mined in a short time span. Time, and the results of the heat treatments, will show the viability of this deposit.

View Gallery @chapter:0 @chapter:0 @chapter:0


# Publication Year: 2014
# Title: Gem craftsmen of Chanthaburi _26
# Abstract: We bought those gems and then proceeded to heat treat them. After heating, we faceted them to enhance their brilliance. The result was gemstones with beautiful colors and high quality, recognized and accepted in the gemstone trade and jewelry industry worldwide. @chapter:31 @chapter:2 @chapter:31


# Publication Year: 2005
# Title: Coated Pink Diamond — A Cautionary Tale
# Abstract: The Diamond Trading Company (DTC) Research Centre had the opportunity to examine a diamond that, on submission to a commercial gem laboratory, was stated to have been HPHT treated. However, spectroscopic analysis yielded data inconsistent with this statement. After further testing, it was determined that this diamond, which originally was probably pale yellow, had been coated to change its color to the equivalent of Fancy Intense purple-pink. Careful examination with a microscope revealed evidence of a coating exclusively on the pavilion facets. Elemental analysis of the coating suggests it may be calcium fluoride with a gold impurity that was added either to generate the absorption responsible for the pink color or to assist as a nucleating agent for the calcium fluoride film. @chapter:36 @chapter:1 @chapter:36


# Publication Year: 2021
# Title: Heat Treatment Effects on the Behavior of the 3161 cm–1 Feature in Low-Iron Metamorphic Yellow Sapphire
# Abstract: Figure 1. Plot of FTIR peak height at 3161 cm–1 of representative yellow sapphires from Sri Lanka (above) and Madagascar (bottom), before and after heating at different temperatures between 500° and 1050°C for six hours.
Heating is the most common treatment to improve the color and/or clarity of corundum. Untreated natural yellow sapphires from metamorphic deposits often have low color saturation; therefore, heat treatment is typically performed to intensify the yellow coloration. However, the chemical composition of the stones, the heating temperatures employed, the duration of the treatment process, as well as the composition of the furnace atmosphere—reducing or oxidizing—are also important factors that influence the color alteration (K. Nassau, “Heat treating ruby and sapphire: Technical aspects,” Fall 1981 G&G, pp. 121–131; J.L. Emmett et al., “Treatments,” in R.W. Hughes, Ed., Ruby & Sapphire: A Gemologist’s Guide, 2017, pp. 197–247).
The identification of heat treatment in a yellow sapphire is challenging for gemologists. Apart from visible inclusion changes, Fourier-transform infrared (FTIR) absorption spectra are one of the few remaining clues to identify the treatment of low iron content metamorphic yellow sapphires. These sapphires as formed are acceptor dominated when [Mg2+] > [Ti4+] + [Si4+] with the charge compensation being accomplished totally or partially by hydrogen (H+) (E.V. Dubinsky et al., “A quantitative description of the causes of color in corundum,” Spring 2020 G&G, pp. 2–28). In corundum, H+ forms a bond with oxygen creating OH–. It is the OH– that is responsible for the broad peak at 3161 cm–1 (and the series of peaks at 3161, 3242, and 3355 cm–1) when associated with Mg2+ (C.P. Smith et al., “Infrared spectra of gem corundum,” Fall 2006 G&G, pp. 92–93). However, the origin of the 3161 cm–1 peak is not well understood. The article by N. Fukatsu et al. (“Incorporation of hydrogen into magnesium-doped α-alumina,” Solid State Ionics, Vol. 162, 2003, pp. 147–159) showed that when OH– is incorporated into Mg2+-doped synthetic sapphire, the 3161 cm–1 peak was not present but a broad band appeared in the 3000 cm–1 region. If the hydrogen is eliminated either in nature or in the laboratory, the trapped hole (h•) forms to provide charge compensation. The trapped hole pairs with Fe3+, creating a trapped-hole-Fe3+ (h•-Fe3+) pair, which is a very strong yellow chromophore in corundum. In this report, the authors aim to study the effects of heat treatment in changing the 3161 cm–1 feature and creating the yellow coloration.
Twelve yellow sapphires reportedly from Sri Lanka and Madagascar that initially displayed a weak to strong 3161 cm–1 peak or a 3161 cm–1 series in FTIR were selected for heat treatment in an oxidizing atmosphere (air) at 500°, 700°, 900°, and 1050°C for a fixed duration of six hours at each temperature. For a final step, some stones were heated at 1550°C in pure oxygen to assure the complete elimination of hydrogen. The samples were fabricated as optical wafers with at least two polished surfaces perpendicular and/or parallel to the c-axis. The samples possess a sufficiently large and clean area to get high-quality FTIR spectra. After each heat treatment step, FTIR spectra were collected at the same position for each sample by fixing it in an identical position in the sample holder.
Heat treatment can cause the H+ to move to different sites by diffusion or at sufficiently high temperatures to diffuse completely out of the sample. The diffusion coefficient of hydrogen in corundum is exponentially dependent on temperature. After heat treatments at 500°C and 700°C, the intensities of 3161 cm–1 peaks and the color appearance of the stones were essentially unaltered. Thus, there is little outward diffusion for a sample of this size. However, heating at 900°C and above for six hours in air will begin to diffuse the hydrogen out of the lattice. As the hydrogen begins to diffuse out, trapped holes form and pair with Fe3+ to maintain charge compensation, increasing the yellow coloration.
At the same time, the amplitude of the 3161 cm–1 feature will decrease proportionally. The test at 1550°C for six hours was conducted in pure oxygen to eliminate any possibility of the water vapor in air contributing hydrogen. With this last step, the outward diffusion of all the hydrogen in the stone was complete, eliminating OH– peaks in FTIR spectra and maximizing the yellow trapped-hole coloration.
Figure 1 shows these heating processes as applied to stones from Sri Lanka with a strong 3161 cm–1 feature and to some of the stones from Madagascar with a weak 3161 cm–1 feature. As expected, both types exhibited a similar diffusion reduction in the initial hydrogen content with temperature and time. The coloration of some of the Madagascar stones was zoned, with areas colored by the h•-Fe3+ pair, by h•-Fe3+ plus Fe3+, and some by Fe3+ only, depending on the distributions of Fe3+ and h•-Fe3+ in the stone. Usually, the zones in which h•-Fe3+ is dominant will increase yellow coloration with high-temperature heat treatment by removing the hydrogen, whereas the areas with Fe3+ alone are rarely strongly zoned.

Figure 2. Sri Lankan sample no. 2801 showing a 3161 cm−1 series (red) in FTIR with initially light yellow color, then altered to 3000 cm−1 broad band series (blue) with a bit stronger yellow zone after heating at 900°C for six hours. Finally, the broad bands disappeared (green) and a much stronger yellow coloration was generated at 1550°C, thickness 3.748 mm, 190 ± 41 ppma Fe.
Interestingly, a characteristic peak at 3161 cm–1 in certain Sri Lankan samples could be occasionally transformed to the broadband series in 3000 cm–1 region with a broad band at 2625 cm–1 when heated at 900°C and above in air, as presented in figure 2. Previously, the 3000 cm–1 broad band series has been reported as indicative of heat treatment observed in Punsiri-type heated blue sapphires (G. DuToit et al., “Beryllium treated blue sapphires: Continuing market observations and update including the emergence of larger size stones,” GIA Research News, 2009, https://www.gia.edu/gia-news-research-nr62609) and could be observed in unheated high-Fe yellow sapphires from basalt-hosted deposits, such as Thailand and Australia (Fall 2016 GNI, pp. 325–327). However, the 3000 cm–1 broad band series could also be found in heat-treated Sri Lanka yellow sapphires, as seen from this study.
In summary, heat treatment was carried out in an oxidizing atmosphere to increase the trapped-hole color centers and deepen the yellow coloration. Sri Lankan samples colored mainly by the h•-Fe3+ pair can produce stronger yellow coloration by heat treatment, but only at high temperatures (900°C and above). The heating temperature at 900°C starts to change the 3161 cm–1 peak/series in FTIR and the color appearance in metamorphic yellow sapphires. It may well be that heating for a much longer time at 900°C would more completely diffuse out the hydrogen. The amplitude of the 3161 cm–1 peak is insignificantly altered when heated at low temperature (below 700°C) but can be greatly reduced when heated at 900°C and above, and sometimes converted to the 3000 cm–1 broadband series, and then it disappears at much higher heating temperature. Although the 3000 cm–1 broadband series might not be indicative of heat treatment in basalt-related yellow sapphires, it is able to indicate heat treatment in Sri Lankan yellow sapphires. Careful consideration should be exercised when using FTIR to identify heat treatment in corundum. @chapter:19 @chapter:0 @chapter:19


# Publication Year: 2019
# Title: Appendix 5: Simplified Tourmaline Species Classification for LA-ICP-MS Data
# Abstract: Abbreviations used below:
TSi: T-site Si atoms per formula.
YZR2+: Y+Z-site total divalent cation.
Vac: Vacancy
Decide which primary group the tourmaline belongs to:
If Na+K(+Rb+Cs) is greater than both Ca(+Pb) and the X-site vacancy (X□apfu), the tourmaline belongs to the alkali primary group. If Ca(+Pb) is greater than both Na+K(+Rb+Cs) and X□apfu, the tourmaline belongs to the calcic primary group. If X□apfu is greater than both Na+K(+Rb+Cs) and Ca(+Pb), the tourmaline belongs to the vacant primary group (Henry et al., 2011).
Alkali-group tourmaline – classify alkali subgroups 1 and 2.
If TSi is greater than 4.5 and YZR2+/(2Li+ YZR2+) is greater than 0.5, the tourmaline belongs to alkali subgroup 1.
If TSi is greater than 4.5 and YZR2+/(2Li + YZR2+) is less than or equal to 0.5, the tourmaline belongs to alkali subgroup 2.
Otherwise the tourmaline belongs to alkali subgroups 3, 4, or 5, which are not considered here.
Alkali subgroup 1
If Al3+ is the dominant trivalent cation on the Z-site and Mg2+ is the dominant divalent cation on the Y-site, the tourmaline is dravite.
If V3+ is the dominant trivalent cation on the Z-site and Mg2+ is the dominant divalent cation on the Y-site, the tourmaline is vanadium-dravite, now redefined as oxy-vanadium-dravite (Bosi et al., 2013).
If Cr3+ is the dominant trivalent cation on the Z-site and Mg2+ is the dominant divalent cation on the Y-site, the tourmaline is chromium-dravite.
If Al3+ is the dominant trivalent cation on the Z-site and Fe2+ is the dominant divalent cation on the Y-site, the tourmaline is schorl.
Alkali subgroup 2
If the tourmaline belongs to alkali subgroup 2, it is elbaite.
Calcic-group tourmaline – classify calcic subgroups 1 and 2.
If TSi is greater than 4.5 and YZR2+/(1.5Li+ YZR2+) is greater than 0.5, the tourmaline belongs to calcic subgroup 1.
If TSi is greater than 4.5 and YZR2+/(1.5Li+ YZR2+) is less than or equal to 0.5, the tourmaline belongs to calcic subgroup 2.
Calcic subgroup 1
If Al3+ is the dominant Z-site cation and Mg2+ is the dominant Y-site cation, the tourmaline is uvite.
If Al3+ is the dominant Z-site cation and Fe2+ is the dominant Y-site cation, the tourmaline is feruvite.
Calcic subgroup 2
If the tourmaline belongs to calcic subgroup 2, it is liddicoatite.
Vacant-group tourmaline – classify vacant subgroups 1 and 2.
If TSi is greater than 4.5 and YZR2+/(2Li+ YZR2+) is greater than 0.5, the tourmaline belongs to vacant subgroup 1.
If TSi is greater than 4.5 and YZR2+/(2Li+ YZR2+) is less than or equal to 0.5, the tourmaline belongs to vacant subgroup 2.
Vacant subgroup 1
If Al3+ is the dominant Z-site cation, and Fe2+ is the dominant Y-site cation, the tourmaline is foitite.
If Al3+ is the dominant Z-site cation and Mg2+ is the dominant Y-site cation, the tourmaline is magnesio-foitite.
Vacant subgroup 2
If the tourmaline belongs to vacant subgroup 2, it is rossmanite. @chapter:12 @chapter:0 @chapter:12


# Publication Year: 2018
# Title: Nephrite Bracelet with Filled Cavity
# Abstract: Figure 1. Two white jade bracelets weighing 62.305 g (left) and 69.422 g (right) with dark color patches similar to the natural skin of some nephrite pebbles. Photo by Jianjun Li.

Nephrite, also called tremolite, is treasured by the Chinese for its fine texture and superior toughness. White nephrite pebbles with some areas of orange or brown skin are called zi yu. Mutton-fat nephrite jade with a natural dark brown, brown, and/or brown-yellow oxide skin is rare and considered premium quality. This skin forms due to natural weathering, and the pebble is polished within river currents. In China, nephrite enthusiasts often aspire to own mutton-fat zi yu jewelry. White jade that is artificially polished into pebbles and partially dyed is often seen in China as an imitation of mutton-fat jade with brown and/or orange skin. Therefore, many traders treat the white primary ore into dyed brown-orange pebbles by artificially dyeing the material. A great deal of white jade with partially dyed color is marketed as mutton-fat zi yu in the Chinese market.
Recently, China’s National Gold & Diamond Testing Center (NGDTC) laboratory received from a client two bracelets with filled cavities that mimicked mutton-fat nephrite with dark brown skin. This treatment process is quite different from the traditional surface staining.
Shown in figure 1 are two bracelets weighing 62.305 and 69.422 g. The white portions were pure with very fine texture. The deep brown parts, which resembled the black skin on some nephrite, were distributed along large fissures, and the sharp color boundaries were accompanied by brown and yellow materials. The black material penetrated the body of the 62.305 g bracelet (figure 2).

Figure 2. Many gas bubbles and spherical pores formed from burst bubbles can be seen in the brown and black areas. Photo by Jianjun Li; field of view 13 mm.
Standard gemological tests were carried out to identify the two bracelets and the deep brown and orange-yellow parts. With the owner’s permission, a dark brown portion was sampled with a knife to obtain small scrapings, which were mixed with KBr powder to form a tablet. Next, infrared spectra were collected using a Nicolet Nexus 470 infrared spectrometer with a resolution of 8 cm–1 and 64 scans per sample.
With a PIKE Technologies UpIR diffuse reflection accessory, reflectance infrared spectra were collected on the white parts of the bracelets. The instrument resolution and scan count were the same as those described above. The reflection spectrum was corrected using the Kramers-Kronig method.
The sample’s spot refractive index was 1.61; specific gravity ranged between 2.95 and 2.96, consistent with nephrite. The white body of the bracelets presented very weak blue-white fluorescence under a 5-watt long-wave UV lamp (365 nm) and was inert under short-wave UV (254 nm). Because of a poor surface polish, the refractive index of the brown-black part could not be measured. The dark parts showed no fluorescence.
Under the gemological microscope, the white bodies presented a cryptocrystalline texture, with some obscure white areas. Dark brown patches on the bracelets appeared compact, with a slightly weak luster and grainy texture. The dark patches on the inner wall of one bracelet contained many spherical pores and gas bubbles of different sizes (again, see figure 2). This feature is common in glass or plastic imitation gemstones, but has never been found in nephrite. Spherical pores are formed from bubbles close to the surface that burst during the polishing process. The brown or dark brown dendritic pattern often found in fractures of natural nephrite (Z. Yin et al., “Nephrite jade from Guangxi Province, China,” Fall 2014 G&G, pp. 228–235) was not observed. Magnification showed that the orange-yellow and dark brown patches were artificially filled.
One of the authors reported on a “filled nephrite” in 2005 (J. Li, “The identification of impregnated nephrite,” Australian Gemmologist, Vol. 22, No. 7, pp. 310–317). After careful testing, a serious mistake in that report has subsequently been identified: the direct transmission FTIR spectra with absorption bands or peaks between 3060 and 2850 cm–1 were incorrectly attributed to the epoxy resin filler. The nephrite in that report was not actually filled at all. Until now, the authors have not found a nephrite that has been bleached and filled with polymer like the B-jadeite jade. The author of the earlier study and a coauthor of the present study (JL) no longer believe that direct transmission infrared spectroscopy detects the treatment of nephrite jade. The author tried to collect direct transmission infrared spectra through the deep brown patches of the two bangles, but experiments show that these areas absorbed the mid-infrared light completely.

Figure 3. Infrared spectra of the white (red line) and brown (blue line) areas of the bracelets are significantly different, with fingerprints that represent the vibration of the -OH (3674 cm–1) and the -CH2- groups (2924 and 2854 cm–1 peaks), respectively. The spectra have been vertically offset for clarity.
As shown in figure 3, there was significant difference between the infrared spectra of the white body (collected using reflection mode) and the brown patches (collected with KBr powder). These clearly represent two different materials.
The infrared spectrum (red line in figure 3, right) from the white body of the bracelets has a fingerprint similar to that of Italian nephrite (see I. Adamo and R. Bocchio, “Nephrite jade from Val Malenco, Italy: Review and update,” Summer 2013 G&G, pp. 98–106), except that the sample does not exhibit the absorption peak of carbonate-associated minerals. This verifies that the white part of the sample is tremolite.
To identify the material in the dark brown part collected with KBr powder (blue line in figure 3, right), we searched databases containing hundreds of spectra libraries purchased by NGDTC using Thermo Scientific OMNIC 9.2 software. Materials with higher degrees of matching included allspice, cellophane, and even opium. This suggests that the dark brown material may be organic. Further advanced testing would be required to conclusively identify the dark brown material.
In the 4000–2000 cm–1 range, the white part shows a spectrum peak of 3674 cm–1, attributed to the stretching vibration of the -OH groups in tremolite; the dark brown part shows a strong absorption band centered at 3429 cm–1 between 3700 and 3100 cm–1. This band is usually associated with hydroxyl groups in the polymer in organic matter. The 2924 and 2854 cm–1 peaks are often attributed to the -CH2- groups, which often appear in the spectra of organic-filled gems (e.g., E. Fritsch et al., “Identification of bleached and polymer-impregnated jadeite,” Fall 1992 G&G, pp. 176–187; M.L. Johnson et al., “On the identification of various emerald filling substances,” Summer 1999 G&G, pp. 82–107). Contamination from human fingerprints or body oils can also lead to absorption peaks within the 3000–2800 cm–1 range, but the absorption is generally weaker. The spectrum of the white part of the sample has a very weak absorption in this region, probably due to human body fat contamination or wax residue left after polishing.
This evidence indicates that the dark brown and orange parts of the samples are fillers. But this filling is obviously different from that in B-jade, where polymer is flooded between the grain boundaries. The filling in these two nephrite bracelets looks more like that in single-crystal gems. Therefore, we propose that the nephrite used in these bracelets had severe pits or cavities, and fillers were used to fill them and make the surface look smooth. The authors want to alert the trade and consumers to this new treatment, whose detection requires access to gemological instruments. Therefore, bringing your nephrite jewelry to a gem laboratory can help avoid unnecessary loss. @chapter:46 @chapter:4 @chapter:46


# Publication Year: -
# Title: Garnet History and Lore
# Abstract: Antique Pyrope Hairpin in the collection of the Smithsonian National Museum of Natural History - Chip Clark, courtesy Smithsonian Institution

                      Thousands of years ago, red garnet necklaces adorned the necks of Egypt’s pharaohs, and were entombed with their mummified corpses as prized possessions for the afterlife. In ancient Rome, signet rings with carved garnets were used to stamp the wax that secured important documents.

The term carbuncle was often used in ancient times to refer to red garnets, although it was used for almost any red stone. Carbuncle was thought to be one of the four precious stones given to King Solomon by God.

Centuries later, in Roman scholar Pliny’s time (23 to 79 AD), red garnets were among the most widely traded gems. In the Middle Ages (about 475 to 1450 AD), red garnet was favored by clergy and nobility.

Red garnet’s availability increased with the discovery of the famous Bohemian garnet deposits in central Europe around 1500. This source became the nucleus of a regional jewelry industry that reached its peak in the late 1800s. @chapter:40 @chapter:0 @chapter:40


# Publication Year: 2017
# Title: Remarkable Twinned Calcite Inclusion in Mogok Ruby
# Abstract: Viewed between crossed polarizers, an included calcite crystal within an unheated Burmese ruby displays dramatic twinning planes. Photomicrograph by E. Billie Hughes; field of view 3.90 mm.

The Mogok Stone Tract in Myanmar (formerly Burma) is one of the world’s most famous sources of ruby, which often forms there in a calcite-marble host. Calcite may occur as an inclusion inside the ruby, as in the example above. In this stone, the calcite is easy to spot between crossed polarizers, which reveal polysynthetic twinning planes that “crisscross” the crystal. While calcite is a common inclusion in ruby, this is the clearest example of calcite twinning this author has seen. Surrounding the calcite crystal is a dense, angular nest of exsolved rutile silk as short needles, a typical scene in rubies from this locality. @chapter:8 @chapter:0 @chapter:8


# Publication Year: 2021
# Title: Laboratory-Grown Diamond with Internal Laser Markings
# Abstract: Figure 1. The 2.44 ct pear-cut CVD-grown diamond with internal spiral markings. Photo by Jian Xin Liao.
With the recent influx of laboratory-grown diamonds into the market and to aid consumer awareness of diamond origin, manufacturers are often marking their laboratory-created diamonds using internal inscriptions. The New York laboratory recently examined a 2.44 ct pear-shaped CVD (chemical vapor deposition) grown diamond with unusual internal spiral markings (figure 1).

Figure 2. Micro image of the largest spiral marking; the line thickness is 40 microns. Photomicrograph by Paul Johnson.
The three spiral markings were black and all in the same plane (i.e., at the same depth). The line thickness of these markings was about 40 microns (figure 2), whereas laser inscriptions are generally less than 20 microns. It was suspected that these markings were created by accidental laser damage rather than laser inscription. Raman mapping of the surface above the markings revealed a much broader diamond Raman peak compared to the rest of the crystal. This is the result of laser damage to the crystal lattice. Further Raman mapping using confocal settings identified a graphite peak at about 1620 cm–1. This offered proof that a laser, graphitizing the diamond, had created the markings.
The “inclusions” likely resulted from the laser marking the surface; this is done to provide a template to guide the polisher in producing the final shape. The intent would have been to score the surface; however, the laser appeared to have been inadvertently focused below the surface, resulting in the unusual internal markings.
As the markings are internal and graphitized, they are considered clarity features. The clarity grade was determined to be SI1, followed by a report comment stating, “Clarity grade is based on manufacturing remnants that are not shown.” @chapter:36 @chapter:1 @chapter:36


# Publication Year: 2018
# Title: Manufactured Gold-in-Quartz Jewelry
# Abstract: Figure 1. The gold veins in natural gold-in-quartz are irregular and show a natural nugget structure below the surface. Photo by Nicole Ahline; field of view 4.79 mm.

Due to its desirability, gold is often imitated with minerals such as pyrite or with gold plating. Gold occurs in small quantities in many kinds of rocks throughout the world. It is typically found in epithermal deposits where hydrothermal fluids deposit gold, along with pyrite and other sulfides, into cracks and faults of rocks—commonly quartz-bearing rocks (J.W. Anthony et al., Handbook of Mineralogy, Vol. 1: Elements, Sulfides, Sulfosalts, Mineral Data Publishing, Tucson, Arizona, 1990). Due to the aggregate structure of this material, the gold contained in natural gold-in-quartz is deposited irregularly, showing a more natural-looking sporadic veining system in the host quartz (figure 1).

Figure 2. Manufactured gold-in-quartz, set in two bracelets and a ring that were submitted for identification reports. Photo by Robison McMurtry.
The Carlsbad lab was recently sent three jewelry pieces—two bracelets and a ring—for identification reports (figure 2). The ring and one of the bracelets were set with numerous white stones cross-cut with yellow metallic veins. One bracelet had black stones cross-cut with similar yellow metallic veining. Standard gemological testing of both the white and black stones revealed properties consistent with quartz; these results were confirmed with Raman spectroscopy. The Raman analysis of the black stones indicated the presence of amorphous carbon, which drew some suspicion.

Figure 3. Unnatural veins in manufactured gold-in-quartz. Left: This vein is filled with both polymer, which is not flush with the host quartz, and gold (field of view 4.79 mm). Center: A vein of polymer running alongside a vein of gold with undercutting visible at the boundary of the polymer vein and the host quartz (field of view 3.57 mm). Right: Polymer fills an incomplete gold vein; the rest of the vein is recessed below the host quartz (field of view 7.19 mm). Photomicrographs by Hollie McBride.
These jewelry pieces initially seemed to contain natural gold-in-quartz. Upon further inspection, the yellow metallic veining system appeared inorganic in the host quartz due to its very consistent appearance in all the stones. In the three pieces, the metallic veins had a spiderweb-like structure, and a colorless polymer was also present alongside the metallic veins (figure 3, left). The colorless polymer areas showed undercutting, and the metallic veining had areas of incomplete filling (figure 3, center and right). These features were consistent with the manufactured gold-in-quartz products that were first introduced to the market at the 2005 Tucson shows (Spring 2005 GNI, pp. 63–64). This material was composed of polymer, quartz, and metallic veining similar to what was observed in the stones we examined. Even with the slight difference in the face-up appearance of the natural and manufactured gold-in-quartz, the manufacturer claims that the only way to clearly distinguish this imitation material is with chemical analysis of the metal alloy.
Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) analyses were performed on the yellow metallic veins in the white and black stones of each bracelet to further separate them from natural gold-in-quartz. Each ablation spot was drilled twice into the veins. The chemistry of the first spot was very similar for the stones in both bracelets. The vein was mainly composed of gold (Au) and silver (Ag) with traces of nickel (0.90–2.67 parts per million weight, ppmw) and copper (23.58–30.02 ppmw). The gold to silver weight ratio (Auppmw/Agppmw) was between 2.71 and 3.33. The chemistry of the second spot on the same position showed little gold or silver and a significant amount of silica, which indicated that the laser had passed through the yellow metallic layer and into the host quartz below.
One natural gold-in-quartz cabochon obtained from the GIA Museum was analyzed for comparison. The veins found in the natural sample (again, see figure 1) were composed mainly of yellow metallic materials, with additional gray metallic minerals. The same experimental procedures were applied to both the yellow and gray areas. The chemistry of the gray metallic areas identified them as an iron sulfide mineral. The chemistry of the first spot on a yellow metallic area showed a large amount of gold and silver with traces of copper (215–257 ppmw). The gold and silver weight ratio (Auppmw/Agppmw) was between 7.84 and 8.04. It was evident that the concentration of gold in the yellow metallic veins in the natural gold-in-quartz was much higher than that of the yellow metallic veins in the white and black panels of the two bracelets. In addition, the natural veins had a higher copper concentration than the two bracelets.
The manufactured gold-in-quartz materials first reported in 2005 are still circulating in the market today. Consumers should be aware of this when purchasing pieces reported to contain gold-in-quartz. The telling indicator of manufactured gold-in-quartz is the consistent texture of its yellow metallic veins. The gold in the natural version is much more sporadic and appears as chunky conglomerated nuggets. @chapter:4 @chapter:0 @chapter:4


# Publication Year: 2016
# Title: African Rhodochrosite and Colombian Quartz with Trapiche Patterns
# Abstract: Left: A 6.0 cm tall rhodochrosite specimen from the N’Chwaning mining area in South Africa. Right: These domed hexagonal quartz slices from Colombia, measuring 3.5–4.5 cm across, exhibit inclusions reminiscent of trapiche emerald. The pattern becomes more distinct when viewed through cross-polarized filters. Photos by Donna Beaton.

	At Tucson's Pueblo show, Germán Salazar (Idar-Oberstein and Bogotá) and Gaetano Lacagnina (L.G. Gemme, Milan) shared a booth that featured an eclectic assortment of gems and minerals. Mr. Lacagnina, who also operates a lab and cutting factory, specializes in unusual and fine mineral specimens. Of particular note were high-quality rhodochrosites, as seen in the image on the left, from the N’Chwaning mining area in the Northern Cape province of South Africa. N’Chwaning, noted for having Africa’s largest manganese reserves, also produces manganite, ettringite, and other Mn-bearing minerals. Noteworthy on Mr. Salazar’s side of the booth were polished hexagonal quartz slices bearing a spoked trapiche-like pattern, shown in the right-hand image. Coincidentally, the quartz was from the Boyacá region of Colombia, which regularly produces trapiche emerald. The patterned areas are found at the core of larger quartz crystals. Viewed in a polariscope, the growth directions and fibrous inclusions are very distinct. Although Mr. Salazar has marketed the slices as “trapiche quartz,” he is considering branding this unique find as “Salazarite.” @chapter:14 @chapter:0 @chapter:14


# Publication Year: 1982
# Title: Gemstones with Alexandrite Effect
# Abstract: The term alexandrite effect refers to the apparent change of color in certain minerals from blue-green or greenish violet in daylight to red or reddish violet in incandescent light. This effect was discovered in chrome-bearing chrysoberyl from the Ural Mountains as early as the beginning of the 19th century. In more recent times, it has also been observed in certain varieties of garnet, corundum, spinel, kyanite, fluorite, and monazite. It has been determined that the absorption spectrum of all alexandrite-like minerals is characterized by transmission maxima in the blue-green and red regions and by a transmission minimum in the yellow region. The color of minerals with two such regions of transmission is determined in daylight (richer in blue and green) by the position of the transmission maxima and in incandescent light (richer in red) by the ratio of transmission in the red and transmission in the blue-violet sections of the visible spectrum. @chapter:13 @chapter:0 @chapter:13


# Publication Year: 1985
# Title: Amethystine Chalcedony
# Abstract: A new amethystine chalcedony has been discovered in Arizona. The material, marketed under the trade name "Damsonite," is excellent for both jewelry and carvings. The authors describe the gemological properties of this new type of chalcedony, and report the effects of heat treatment on it. Although this purple material is apparently a new color type of chalcedony, it has the same gemological properties as the other better-known types. It corresponds to a microcrystalline form of amethyst which, when heat treated at approximately 500°C becomes yellowish orange, as does some single-crystal amethyst. @chapter:2 @chapter:0 @chapter:2


# Publication Year: 2013
# Title: Petrochemical Characteristics and Genesic Significance of Luodian Jade from Guizhou
# Abstract: Luodian jade is a new nephrite variety discovered in 2009 at Luodian County in China’s Guizhou province. The nephrite formed within the metasomatic zone between the Varisian gabbro and calc-silicate. Geochemistry and petrology studies of both the white and greenish white varieties indicate  98% and 95% tremolite, respectively. Tremolite has an ideal chemical formula of Ca2(Mg, Fe)5[Si4O11]2(OH)2, with Mg and Fe substituting for each other to form a solid solution series. Al can also substitute for a small amount of Mg and Fe, while Na, K, and Mn can substitute for Ca and Mg. Chondrite-normalized REE (rare earth element) patterns of the nephrite and the host rock are very similar with enrichment of LREE (light rare earth elements). The concentration of REE is lower in the nephrite than that in the host rock. The La/Yb ratio is also much higher in nephrite, which indicates a higher differentiation of REE in nephrite. Compared to the greenish and greenish white nephrite, the white variety is more evolved. This tells us that the nephrite deposit formed in two stages. Ca/Mg is higher in the greenish and greenish white varieties, meaning they were formed when Mg was unsaturated in the fluid; the white variety formed when Ca and Mg were both saturated. The substitution of trace-element V and Cr into the crystal lattice is closely related to the saturation of Mg in fluid. V and Cr are also the chromophores of the greenish and greenish white varieties. Nephrite formation is caused by metasomatism during the interaction with thermal fluid brought by the intrusive gabbro and the limestone. Limestone provided Ca and Mg, while the fluid brought Si, K, Na, and Al. @chapter:46 @chapter:0 @chapter:46


# Publication Year: 2018
# Title: Pink Tourmaline in Spodumene
# Abstract: Figure 1. Appearing as if suspended in water, a pink tourmaline inclusion in spodumene is illuminated by diffuse and fiber-optic illumination. Photomicrograph by Jonathan Muyal; field of view 7.19 mm.
The pegmatitic mineral spodumene commonly exhibits fluid inclusions as well as muscovite-mica, feldspar, and clay mineral inclusions (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Vol. 1, ABC Edition, Zurich, 1986). A colorless 7.85 ct emerald-cut spodumene, purportedly from Afghanistan, was of particular interest for the eye-visible pink tourmaline crystal inclusion (figure 1) under the table facet. The mineral inclusion’s identity was confirmed by Raman microspectrometry analysis.

Although green tourmaline inclusions in spodumene have been documented (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Vol. 3, Opinio Publishers, Basel, Switzerland, 2008, p. 642), very few references are found in the literature, and pink tourmaline in spodumene remains a rare occurrence. The transparent inclusion showed a well-formed trigonal prismatic crystal habit with fine vertical striations along its length (parallel to the c-axis). It exhibited a hemimorphic nature, with a flat termination on one end and a low pyramidal termination on the other. Abundant uneven wavy fractures, more or less perpendicular to the c-axis, were also visible within the crystal.
Of interest were some triangular etch marks common to spodumene. Although at first they appeared to be on the inclusion’s surface, they were actually on the spodumene interface. Additionally, the interface space exhibited vibrant iridescent colors when illuminated with oblique fiber-optic illumination (figure 2). This special guest inclusion thus gives the impression of having been “dressed and embellished” by its host spodumene and is displayed in its best attire.

Figure 2. Diffuse and fiber-optic illumination reveal the fine striations common to tourmaline along the length and the shallow triangular etch markings typical of spodumene along the interface, as well as vivid iridescent colors. Photomicrograph by Jonathan Muyal; field of view 1.26 mm.
Such a large tourmaline inclusion specimen in spodumene also provides valuable mineralogical information for the gemologist. The syngenetic inclusion and the host reflect their common pegmatitic geological genesis. The lithium-bearing granitic pegmatitic occurrence of spodumene strongly suggests that the inclusion is a lithia tourmaline variety, with lithium and aluminum substituting for iron and magnesium.

While spodumene is not known and prized for its inclusions, the beautifully highlighted pink tourmaline inclusion makes this gem a rare collector specimen. @chapter:8 @chapter:0 @chapter:8


# Publication Year: -
# Title: Major Diamond Find Brightens Market
# Abstract: The 1,111 ct. rough found by Lucara Mining in the Kerowe Mine in Botswana is only the second time in history that a diamond weighing more than 1,000 carats has been found. The company plans to auction the diamond next year. Photo courtesy Lucara Mining

The news from Lucara Mining, which found three huge diamonds – 1,111, 813 and 374 carats − all in the same week from the company’s Kerowe Mine in Botswana, brightened an otherwise lackluster diamond market.

Two of the diamonds are the second and sixth largest ever found.

All three will be sold in Antwerp early next year, according to Lucara. Given the enormous wealth some buyers are putting into major diamonds and colored gems, the buyer of the 1,111 carat (ct.) rough will likely go for the maximum final cut size, striving to exceed the 530 ct. Cullinan I, the world’s largest colorless diamond that is a centerpiece of the British Crown Jewels, and the 545 ct. Golden Jubilee, a yellowish brown diamond in the Crown Jewels of Thailand. The final cut, of course, will depend upon whether the inclusions and fissures within the stone will permit such a large stone.

The enormous wealth being spent on top diamonds was evident at recent Sotheby’s and Christie’s auctions. As reported around the world, a Hong Kong businessman, Joseph Lau, paid a world record of $48 million for a 12.08 ct. Fancy Vivid blue diamond – at $4 million per carat, it was also the record per-carat price ever paid for a gemstone. The day before, he paid $28.5 million for 16.08 ct. Fancy Vivid pink diamond.

	The $48 million Blue Moon Josephine, a 12.08 ct.  Fancy Vivid blue, has become the most expensive gemstone ever sold at auction. Its $4 million per carat price exceeded the previous record by $1 million. Photo courtesy Sotheby’s
Lau named both diamonds, which were graded by GIA, after his daughter, Josephine. Last year, he paid a record-breaking $32.6 million for a 9.75 ct. Fanvy Vivid blue diamond and named it Zoe after his other daughter.

In the more commercial side of the diamond market, major diamond producers have trimmed rough sales way back as the industry continues to grapple with high inventories, diminished credit and stagnant demand.

De Beers’ Dec. 7-11 sight is expected to be a repeat of November’s $70 million allocation – the smallest since the world financial crisis in the fall 2008. De Beers has reportedly returned to deferring purchases from its own mining partners, in particular Debswana, a practice it has not done in 20 years, when Russian diamonds were flooding the market and depressing prices for smaller stones.

Alrosa, the agency that mines and sells Russia’s diamonds and Rio Tinto, which owns Argyle Diamond Mine in Australia and a majority share of Diavik in Canada, have instituted provisions that allows their clients to defer purchases.

Alrosa rough diamond sales volume fell 42% short of its plan for the third quarter of the year, according to a company statement. The decline was especially steep in September, when the company not only slashed prices 8%, but also allowed its clients to defer up to 50% of their purchases. The company, which held its prices in October, had forecast $5 billion in revenues for the year, but analysts believe actual sales will come in about $3.6 billion.

The company’s diamond production totaled 23 million carats through the third quarter, down 5.8 million carats from the same period of 2014. But revenues-per-carat sales were 3.5% higher, indicating that Alrosa was concentrating its sales into larger goods and stockpiling the smaller goods.

	The 16 ct. Fancy Vivid Pink diamond sold for $28.5 million to the same buyer who bought the record-breaking blue diamond. Photo courtesy Christie’s

	Retail
Jewelry demand in the U.S. is growing, though slowly this year. According to U.S. Department of Commerce data, sales of fine jewelry increased 4.8% in September, over the same month last year. Much of that increase went to online sellers, which include brick and mortar retailers who have an e-commerce division.

Retail analysts are expecting jewelers to discount heavily during holiday sales, even as they predict a respectable season. Price cutting began early with one major department store, Macy’s, advertising 30% off on engagement rings during the holiday season.

Blue Nile, the leading online diamond seller, has scaled back its sales growth estimates for 2015, expecting its yearly sales to total between $488 and $498 million, instead of the originally forecast $505 million. Last year’s total sales were $473.5 million. The company is basing its new forecast on a third quarter sales increase of 4%.

Worldwide, demand from luxury watches plunged 12% in all major markets in October, compared to the same month last year. The Federation of the Swiss Watch Industry reported: sales to Hong Kong fell 39% to $258 million; exports to the U.S. declined 12% to $232 million; and orders from China declined 5% to $120 million. Exports to other European countries were down by 4% to 5%. @chapter:49 @chapter:3 @chapter:49


# Publication Year: -
# Title: 2018 Tucson Events Encourage Alumni to Connect with GIA – and Each Other
# Abstract: From left: Anna Barinova, Olga Galant, Marion Kurochkina and Patrick Dreher pose with a special representation of Richard. T. Liddicoat at the 2018 Party at the GIA Gem Mine in Tucson recently.

More than 400 alumni and guests from 15 countries gathered for the 2018 Party at the GIA Gem Mine in Tucson recently to re-connect with former classmates, meet new industry friends, and perhaps even establish a new business relationship.

This year, it was also an opportunity to celebrate what would have been the 100 birthday of Richard T. Liddicoat, the world-renowned gemologist, statesman for the gem and jewelry industry and beloved second president of GIA. Photos, mementos and videos highlighting Liddicoat’s life and legacy were on display at the event and Susan Jacques, president and CEO of GIA, paid tribute to his contributions to GIA and gemology.

Liddicoat served as an instructor, president and chairman of the board of GIA for more than 60 years. He and his colleagues established the universal standards for evaluating the quality of diamonds – the 4Cs of diamond quality and the International Diamond Grading system for D-to-Z diamonds – and he was editor-in-chief of Gems & Gemology for more than 50 years.

Liddicoat was also the guiding force, along with GIA veteran Robert Ernest, behind the creation of the GIA Alumni Association in 1982. They recognized the benefit of organizing GIA graduates around the world to encourage and promote education, news and business networks that support integrity and knowledge in the gem and jewelry industry. Today, the organization is more than 120,000 members strong with 70 chapters around the world.

“Some of you may have personally known or met Mr. Liddicoat and remember your encounters with him with a smile,” Jacques said. “He had a way of making you feel like you were the most important person to him in that moment. Mr. Liddicoat relished time spent with students, graduates and those who shared his passion for gemology around the globe.”

Susan Jacques, president and CEO of GIA and Larry French, chief officer of North American strategies for the Gianmaria Buccellati Foundation, with Catherine Zheng grand prize winner of the 2017 Gianmaria Buccellati Foundation Award for Excellence in Jewelry Design.
The event was also an opportunity to display the original design renderings of the finalists of the first-ever Gianmaria Buccellati Foundation Award for Excellence in Jewelry Design. Catherine Zheng, a real estate broker who studied jewelry design in Carlsbad, was shocked and thrilled when Jacques that she was the grand prize winner.

Jacques then kicked off the always exciting and competitive live auction, led by GIA alumni Joseph DuMouchelle and Lindy Adducci, of DuMouchelle Auctions, who volunteer their professional services each year. All proceeds from the event support the Alumni Endowment Fund. This year’s event raised more than $40,000 from event tickets and the silent and live auctions. More than 70 items, including loose gemstones and pearls, designer jewelry, mineral specimens, equipment, books and more were available to bid on.

 “A special thank you to all of our auction contributors, supporters, event volunteers and attendees,” said Kate Donovan, manager of global alumni relations. “We look forward to seeing you all next year.”

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Alumni Leadership Breakfast
GIA Alumni Association chapter leaders and senior GIA executives also gathered in Tucson for a breakfast meeting that included interactive dialog between alumni volunteer ambassadors and GIA executives who presented and shared GIA’s commitment to support alumni worldwide with programs and expanded benefits.

More than 40 leaders from 15 chapters attended, along with GIA executives Susan Jacques, president and chief executive officer; Bev Hori, senior vice president of education and chief learning officer; Duncan Pay, newly appointed chief academic officer; Jennifer Wilson, senior vice president and executive counsel; Seung-Hae Moon, managing director of Asia Pacific; Robert Weldon, director of the Richard T. Liddicoat Gemological Library and Information Center; Susan Schindelar, vice president of global marketing; and Stephen Morisseau, director of corporate communications.

More than 40 leaders from 15 chapters attended gathered in Tucson for a breakfast meeting with GIA executives to discuss alumni programs and activities. Photo by Anna Cournoyer/GIA
Kate Donovan, manager of global alumni relations, welcomed the attendees and thanked all of the global alumni leaders (and chapters) for their work throughout the year to support local graduates, students, the industry and the public.

Jacques expressed her enthusiasm for the Alumni Association and assured the group of GIA’s commitment to support chapter initiatives by providing relevant resources. She provided an update on GIA services and spoke about Symposium, encouraging the group to sign up. She also urged the group to actively reach out to new alumni and invite them to participate in local chapter activities.
GIA Exhibits and Displays
GIA representatives were available at several booths and displays throughout the Tucson shows. GIA’s main booth at the AGTA show offered information on On-Campus and Distance Education; scholarships; laboratory services; and instruments.

The renderings of the 12 finalists for the first ever Gianmaria Buccellati Foundation Award for Excellence in Jewelry Design were also available to view. The competition was open to individuals who successfully completed a 2017 Jewelry Design course at any GIA campus worldwide. The winner was announced at the alumni party.
Tucson Gem and Mineral Show
The GIA museum showcased Liddicoatite tourmaline’s unrivaled variety of colors and intricate zonation. Liddicoatite was recognized as a new mineral species in 1977, named in honor of Richard T. Liddicoat (1918–2001), then president of GIA, in recognition of his enormous contribution to gemological knowledge and professionalism.

The Richard T. Liddicoat Library and Information Center displayed an exhibit that explored the history of crystallography through rare books, mineral specimens. @chapter:38 @chapter:3 @chapter:38


# Publication Year: 2015
# Title: Update on Rock Creek Sapphire Deposit
# Abstract: Figure 1. Excavators and a washing plant on Gem Mountain process gravel for sapphire recovery. Photo by Warren Boyd.

Recently, Montana-based Potentate Mining LLC secured approximately 3,000 acres of sapphire-bearing ground covering the famous Rock Creek sapphire district near Philipsburg, Montana. Since the discovery of these sapphire deposits in the 1890s, this is the first time that one company has consolidated such a large land position, encompassing the old alluvial sites as well as the area on the hills in between these old workings (figure 1). Potentate has assembled a team of highly experienced placer miners, geologists, mining engineers, and heavy equipment operators to recover and process the sapphires from this mine.

The Rock Creek district sapphire deposits occur in debris flow, colluvium, and secondary alluvial deposits (figure 2). Although the bedrock for these deposits has not yet been defined, Potentate plans further geological mapping and geophysical surveys in the near future to uncover these sources.

Figure 2. A trench on Gem Mountain showing the sapphire-rich colluvium on the hilltops between the previously worked gulches. Photo by Keith Barron.
To date, the rough sapphires recovered from the bulk sampling pits range in size from 0.25 ct to over 20 ct. Approximately 15% of this rough occurs naturally in marketable colors, including pink, orange, orange-pink, lavender, golden yellow, blue-green and green, and fine blue (figure 3). A substantial percentage of the remaining rough responds very well to heat treatment technologies that improve clarity and turn greenish and grayish rough to desirable colors such as blue, orange, yellow, pink, and parti-color.

Figure 3. A selected assortment of unheated rough sapphires from the Rock Creek deposit weighing from 0.50 to 17 ct. Photo by Warren Boyd.
The high-grade concentration of the sapphires recovered from the various test pits, and the substantial inferred rough sapphire resource on Gem Mountain, indicate that Potentate would be able to provide a long-term, consistent supply of sapphire rough to the global market (figure 4). Potentate would be the only large-volume source for the Rock Creek sapphires. The company is developing a marketing strategy that would provide sustainable supply chain guarantees to their clients. These clients including wholesale gemstone cutters, polishers, and fine jewelry retailers would in turn be able to provide guarantees of origin and the presence (or absence) of any heat treatment to their consumers.

Figure 4. A selection of natural and heat-treated Rock Creek sapphire ranging from 0.50 to 4.70 ct. Photo by Jeff Scovil. @chapter:21 @chapter:0 @chapter:21


# Publication Year: -
# Title: Valentine's Day Ideas: Red Gems
# Abstract: Think red for Valentine’s Day – as in red gemstones. The world of red gems is fascinating. They’re hot, sexy, confident, passionate... and never boring. Each red gem has its own personality – which radiates from every facet.

If you are shopping for a red gemstone for Valentine’s Day, there are several intriguing choices available and one is bound to be right for you. Colored stone experts at GIA (Gemological Institute of America), the world’s foremost authority in gemology, provide the following insightful glimpses into four of the most popular red gemstone choices:

Ruby: King of Red Gemstones
Mined in exotic locales around the world – including Myanmar, Madagascar, East Africa, and Sri Lanka – the ruby is the undisputed king of red gems. Ruby offers a distinctive range of red hues that vary from light (pinkish) to dark, velvety reds, and hits a brighter red in between. And, ruby is very hard – second only to diamond in hardness (resistance to scratching).

What’s the best ruby shade? It’s the one that speaks to you, as the potential wearer of this appealing gem. View the spectrum of red hues, and see which one best fits you. Keep in mind that vivid rubies are considered the highest quality, but they are rare and will thus be more expensive.

Spinel: The Great Pretender
GIA’s colored stone experts point out that quite a few famous “rubies” in royal jewels throughout the world are actually spinels – some even reside in the British Crown Jewels. Spinel has been mistaken for ruby for centuries.

Now that it has come into its own, spinel fans love its brilliance and hardness. They are also captivated by its rich reds, although the gem appears in a spectrum of other colors. Spinel is a durable gem that is affordable but also uncommon. It’s mined in Myanmar, Sri Lanka , Tanzania, Tajikistan (part of the former Soviet Union ) and Vietnam.

Garnet: The Popular Gem
Although garnets appear in many colors, red is the most admired. It’s also plentiful and affordable. Garnet is very durable, so it’s ideal for daily wear.

The three species of red garnet are almandine, rhodolite, and pyrope. Almandine garnet is a medium-red color. Rhodolite is found in red with purple or raspberry overtones. Pyrope, from the Greek word pyropus meaning “fiery-eyed,” is the darkest red garnet. The finest specimens have a glowing red color. Garnets are mined in East Africa, India and Sri Lanka .

Tourmaline: A Colorful Character
This colorful gemstone occurs in more colors and color combinations than any other gemstone variety, according to GIA. In the tourmaline family, a red gemstone is referred to as a rubellite. Widely available, rubellites also come in larger sizes, making them a favorite choice for contemporary jewelry. Important sources of rubellite are Brazil and Nigeria.

When shopping for gemstones, it’s advisable to go to a jeweler who has credentials from GIA, such as a Graduate Gemologist (GG) or Accredited Jewelry Professional (AJP). GIA also offers identification reports on gemstones, including those discussed here, to verify their authenticity. @chapter:40 @chapter:2 @chapter:40


# Publication Year: 2023
# Title: An Environmental, Social, and Governance Assessment of Marine Pearl Farming
# Abstract: Figure 1. Pearl diver collecting shells from the wild. Photo courtesy of Pearls of Australia: Cygnet Bay Pearl Farm, Western Australia.
Farming pearl oysters is an important economic activity that, when done sustainably, can also provide valuable environmental and social benefits. To gain an evidence-based understanding of the sustainability challenges and opportunities facing marine pearl farming and their intersection with environmental, social, and corporate governance (ESG), The Nature Conservancy (TNC), a U.S.-based nonprofit, conducted an ESG assessment of an Australian pearl farm. This pilot project was intended to guide the development of a sector-wide ESG and sustainability assessment framework. The project was supported and funded by GIA as part of its global effort focused on education and the promotion of responsible practices.
Pearl oysters filter water at rates that are often higher than those reported for other oyster species. This filtration process contributes to waste treatment through the uptake of not only nutrients (nitrogen and phosphorus) but also heavy metals (S. Gifford et al., “Quantification of in situ nutrient and heavy metal remediation by a small pearl oyster (Pinctada imbricata) farm at Port Stephens, Australia,” Marine Pollution Bulletin, Vol. 50, No. 4, pp. 417–422; L.T. Barrett et al., “Sustainable growth of non-fed aquaculture can generate valuable ecosystem benefits,” Ecosystem Services, Vol. 53, 2022, article no. 101396). Pearl oysters are hung in baskets suspended from long lines, and these structures in which they are farmed provide habitat for a variety of fish and invertebrates (S.J. Theuerkauf et al., “Habitat value of bivalve shellfish and seaweed aquaculture for fish and invertebrates: Pathways, synthesis and next steps,” Reviews in Aquaculture, Vol. 14, No. 1, 2022, pp. 54–72). If the negative impacts of pearl farming can be mitigated and effective sustainability strategies implemented through waste reduction, recovery and reuse, disease mitigation, and avoidance of overstocking, pearl farming could significantly benefit regional economies and local marine environments.
TNC’s 2019 report titled Towards a Blue Revolution provided comprehensive guidance for evaluating critical aquaculture systems. Since the report’s publication, TNC has built a science-based tool to assess industry and company operations. This tool takes into account factors related to the natural environment as well as the inherent and unique characteristics of a sector or company’s operations. The tool has been designed to consider environmental data and the health of local ecosystems, enabling the identification of potential environmental benefits via restorative aquaculture, which has the potential to generate a net positive ecosystem outcome. This approach sets it apart from other sustainability assessment frameworks, risk assessments, and life cycle assessment methodologies.

Figure 2. The pearl oysters are partially opened to allow seeding. Photo courtesy of Pearls of Australia: Cygnet Bay Pearl Farm, Western Australia.

Figure 3. Seeding Pinctada maxima pearl shell. Photo courtesy of Pearls of Australia: Cygnet Bay Pearl Farm, Western Australia.
Between February and May 2023, the assessment was conducted on Cygnet Bay Pearl Farm (CBPF; see figures 1–3), a company that produces pearls from Pinctada maxima north of Broome, Western Australia, using both wild capture and hatchery operations. CBPF is an operation of Pearls of Australia (PoA). Using the TNC framework, a number of overarching factors were assessed:

Company capacity, ethics, and management measures
Impacts on wild stocks from source of stock, hatchery escapes/interbreeding, and macrofauna interactions
Reliance on added feed and chemicals
Habitat impacts
Water column effects (e.g., temperature, salinity, light penetration, and chemical characteristics of seawater at different depths)
Disease
Use of resources: fresh water, land, and energy

The assessment showed that CBPF meets or exceeds all essential requirements within the ESG framework, including the company capacity, ethics, and management metrics. The company has no compliance issues associated with sustainability metrics, and an internal management team oversees sustainability topics and implementation. CBPF adheres to the Pearling Environmental Code of Conduct, developed by Australia’s Pearl Producers Association in 2002 and updated in 2007. The farm has Marine Stewardship Council certification, meeting independent, third-party ecological sustainability standards. It operates within a country that has an effective governance, legal, and enforcement system in place to manage the industry into the future.
Regarding the social component of ESG, CBPF forms part of the Banararr Steering Committee (BSC) of the Bardi people, the traditional owners of the area. The BSC’s role is to establish a positive relationship between CBPF and the Bardi traditional owners. Any amendment, use, or development of the area is discussed by the BSC together with relevant topics affecting the community at large, including school, transport, and fishing. Dedicated cultural heritage tours managed by Bardi people form part of the ecotourism offered at Cygnet Bay Pearl Farm. CBPF is active in research, housing the Kimberley Marine Research Station, and parent company PoA currently partners with the Marine Bioproducts Cooperative Research Centre. This research focuses on better understanding the implications and potential positive effects on fish and invertebrates that grow naturally on PoA farms.
CBPF could already be providing environmental benefits to the surrounding area through restorative aquaculture practices. Based on a general understanding of ecosystem services associated with oyster aquaculture, CBPF does meet the criteria for restorative outcomes, such as increased cycling of water and nutrients and providing habitat to other species. However, the extent to which these ecosystem services positively impact broader environmental outcomes remains unknown, in part because of the limited understanding of anthropogenic effects on water quality and habitat loss in the area.
Overall, the assessment provided an effective means to evaluate CBPF for its management and approach to ESG, the extent to which cultural communities are considered, the company’s engagement with voluntary certification and codes of practices, and its awareness of key environmental risks and negative impacts as well as positive impacts.
At the same time, additional needs for TNC’s ESG Assessment Framework have been identified. Brood stock sourcing and handling, biosecurity, and genetic risks are all areas that require additional research. One hundred percent utilization of the oysters farmed should be an explicit goal and assessment factor. The assessment should also consider the legacy effects of aquaculture equipment (e.g., recovery, reuse, and recycling), as well as the origin and species status of shells utilized to manufacture nuclei. Once these considerations are addressed, the TNC’s ESG Assessment Framework should provide an effective sector-wide approach. @chapter:53 @chapter:4 @chapter:53


# Publication Year: 2017
# Title: Coated Beryl Imitating Emerald
# Abstract: Figure 1. Left: The drilled green briolettes mounted in the pair of earrings submitted for identification. Right: Fluid inclusions, crystals, and two-phase inclusions proved the stones’ natural origin; field of view 2.6 mm. Photos by Lai Tai-An Gem Lab.
Two major issues related to emerald are origin determination and the presence and quantity of fillers. An emerald’s value depends in part on the quality of the stone and treatments applied, so examination with a gemological microscope is an essential part of any analysis.

A pair of earrings (figure 1, left) weighing a total of 84.06 grams was submitted to the Lai Tai-An Gem Lab for identification. The earrings consisted of numerous green drilled briolettes with a vitreous luster. The client, who claimed they were natural emeralds, granted permission to remove one piece to aid in identification. Testing gave a spot refractive index of 1.57, a specific gravity of 2.67, and an inert reaction to both short-wave and long-wave UV, consistent with beryl. Microscopic observation revealed liquid, crystal, and two-phase inclusions (figure 1, right). Infrared and Raman spectroscopy indicated that the loose stone, along with the similar stones still in the earrings, were beryl. Epoxy peaks at 3056, 3037, 2964, 2931, and 2872 cm–1 were obtained by FTIR spectroscopy (figure 2). However, the green color was unusual in that it appeared to be concentrated on the surface, which was confirmed by additional testing.

Figure 2. FTIR spectroscopy showed epoxy peaks at 3056, 3037, 2964, 2931, and 2872 cm–1.

Figure 3. Left: Magnification with diffused illumination clearly showed the concentrated green areas of the coating and the boundaries of the underlying host beryl. Photomicrograph by Lai Tai-An Gem Lab; field of view 4.4 mm. Right: An SEM image from the specimen. The area labeled A shows the coated layer on the surface, while B shows facet boundaries without coating.
Magnification with diffused illumination clearly showed concentrated patches of green color with “colorless” boundaries (figure 3, left), as often seen in diffusion-treated stones such as corundum. Further observation by scanning electron microscopy (SEM) indicated a coating on the faceted surface (figure 3, right). DiamondView imaging revealed the fluorescence reaction of the underlying host beryl where the coating had been worn away at the facet junctions: When exposed to the ultra-short-wave UV of the DiamondView, the “colorless” areas reacted with a strong orange fluorescence (figure 4). UV-Vis-NIR spectra revealed differences between the test stone and a reference emerald. While emerald normally exhibits Cr3+-associated main absorption bands at approximately 620 and 430 nm, the examined samples showed strong absorption bands at approximately 680 and 360 nm, as well as weaker bands at 620 and 430 nm (figure 5)

Figure 4. DiamondView imaging showed where the coating had been worn away at the facet junctions. The colorless areas reacted with a strong orange fluorescence after exposure to the short-wave UV radiation.

Figure 5. UV-Vis-NIR spectra show the differencesbetween a reference emerald, which exhibits significant Cr3+-associated main absorption bands at approximately 620 and 430 nm only (red trace), and the examined sample, which contains absorption bands at approximately 680 and 360 nm in addition to the 620 and 430 nm bands (green trace).
Coatings have been applied to various gemstones for decades, and most of the time they are easy to identify. Although this identification was not particularly challenging, it does show the importance of thoroughly examining jewelry in case treated stones have been incorporated into the design. @chapter:18 @chapter:0 @chapter:18


# Publication Year: 1999
# Title: Winter 1999 Gem News International
# Abstract: Diamonds
            Can Angolan Diamonds be Identified by Country of Origin?
            A Visit to Venezuelan Diamond Mines
Colored Stones and Organic Materials
            Matte-Finished Montana Agates
            Dickite: Consider the Odds
            Star Ekanite
            “American Golden Opal” from Nevada
            The Formation of White Zones in Mexican Opals During Fashioning
            An Update on the John Saul Ruby Mine
            Ruby from Songea, Tanzania
            Another Source for Bicolored Sapphire: Tunduru, Tanzania
            Spessartine from Nigeria
            Tremolite Rock from China Represented as “Longxi Jade.”
            Tsavorite from Madagascar
Treatments
            The Chemistry of Emerald Fillers
            Hematite Coating on Heat-Treated Garnet
            Factors in the Heat Treatment of Corundum
Synthetics and Simulants
            Manufactured Products Imitating Charoite
Miscellaneous
            More on “Internal” Carving: Now Done to Synthetic and Natural Quartz
Announcements
            Basel 2000
            International Rough Diamond Conference
            ISA Personal Property Appraisal Courses
            Kremlin Gold at the Houston Museum of Natural Science
            Treasures from Topkapi Palace
            West Coast Antique & Period Jewelry Seminar 2000
            Gemstones at Upcoming Scientific Meetings

To view the full section, download the PDF above. @chapter:4 @chapter:0 @chapter:4


# Publication Year: 2014
# Title: Star Opal
# Abstract: Figure 1. This 2.39 ct transparent opal with a light brownish yellow bodycolor possessed a six-rayed star. Photo by Lhapsin Nillapat.

              Opal is best known for displaying play-of-color. It may also display asterism, though star opal has only been reported from Idaho, and a perfect six-rayed star is exceptionally rare (J.V. Sanders, “The structure of star opals,” Acta Crystallographica, Vol. A32, 1976, pp. 334–338). The Bangkok laboratory recently had the opportunity to examine a transparent star opal (figure 1). The 2.39 ct light brownish yellow cabochon displayed a distinct six-rayed star.

Standard gemological testing gave a spot RI reading of 1.43 and a hydrostatically calculated SG of 2.10. When exposed to ultraviolet radiation, the stone fluoresced strong bluish white under long-wave and weak bluish white under short-wave UV. It phosphoresced green after exposure to long-wave UV. Advanced gemological testing by energy-dispersive X-ray fluorescence (EDXRF) confirmed a silica-rich material with some additional trace elements, including aluminum and iron. All of these properties were consistent with opal.

Microscopic examination revealed large parallel planes with play-of-color intersecting to form a hexagonal pattern (figure 2). This is responsible for producing the six-rayed star. This unusual stone serves as a reminder that, unlike asterism in other gem materials, the star in opal is caused by diffraction of light from faults or imperfections in the packing arrangement of silica spheres.

	Figure 2. This photomicrograph of the opal shows the intersection of large parallel planes with play-of-color, producing asterism. Photomicrograph by Charuwan Khowpong; magnified 15×. @chapter:48 @chapter:0 @chapter:48


# Publication Year: 2014
# Title: Pearl Newsletter: Margaritologia
# Abstract: Margaritologia, a quarterly newsletter on pearls, was recently launched by Elisabeth Strack.

              The Greek word for pearl, margaritēs, was used by Theophrastus in the fourth century BC in the first known effort to explain the scientific origin of the beloved organic gem. Margaritologia, or “the science of pearls,” is a newsletter recently launched by Elisabeth Strack, founder and director of Gemmologisches Institut Hamburg and author of the comprehensive book Pearls. Ms. Strack is also a member of G&G’s editorial review board.

The newsletter, published four times a year in English and German, in print and electronic versions, offers a forum for pearl research findings and news. Topics range from science and history to pearl grading and testing, farming, and market conditions. The first issue, published in October, featured articles on Vietnamese cultured pearls, DNA fingerprinting of pearls, the International Gemmological Conference in Hanoi, Spondylus pearls, a Mikimoto necklace, and a museum exhibition in Mecklenburg, Germany.

A yearly subscription to Margaritologia is €70, with a discounted rate for CPAA or NAJA members. More information can be found at www.gemmologisches-institut-hamburg.de. @chapter:53 @chapter:4 @chapter:53


# Publication Year: 2018
# Title: HPHT-Processed Diamond Fraudulently Represented as Untreated
# Abstract: This 6.30 ct round brilliant diamond (left) with a fraudulent inscription of a GIA report number (right) from a similar-looking diamond was confirmed to have been HPHT processed for color improvement. Photos by Tony Leung (left) and Billie Law (right).
The Hong Kong lab recently encountered another instance of fraud: A natural but HPHT-treated round brilliant diamond (above left) weighing more than 6 carats submitted for verification service was found to be inconsistent with the claimed GIA report issued a few months prior for an untreated diamond. Moreover, the GIA report number and another inscription on the girdle, both supposedly laser-inscribed by GIA (above right), looked convincing but were also found to be fraudulent.

The HPHT-processed round brilliant was believed to have been carefully selected to match the original diamond—its color grade (F) matched, and only minor differences were observed in carat weight and measurements. The HPHT-processed diamond weighed 6.30402 ct and measured 11.73–11.82 × 7.32 mm, whereas the original one weighed slightly less (6.30216 ct), and measured 11.72–11.83 × 7.32 mm. Furthermore, the IF clarity of the HPHT-treated stone was an improvement over the VVS1 clarity of the natural stone.

Despite all the efforts put into those convincing features and measurements, spectroscopic testing easily revealed the stone’s true identity. Infrared absorption spectroscopy showed the HPHT-processed diamond was type IIa, but the original diamond was type Ia. Photoluminescence (PL) spectra were collected at liquid nitrogen temperature with various excitation wavelengths. The slight reversal in the ratio between the 575 and 637 nm peaks (NV centers), together with other spectroscopic features, confirmed the stone had gone through an HPHT treatment process for color improvement. A strain pattern observed under cross-polarized light ruled out the possibility of a synthetic diamond.

This case should raise awareness among the industry and the public that, although rarely encountered in larger stones, this kind of fraud does exist. Verification services at GIA confirm that an item is exactly the same as the one described on a previous report and has not been recut or treated—or, as in this case, replaced with a similar-looking stone. This provides a simple way to check for any type of fraudulent activity if there is doubt about the origin of a diamond. @chapter:36 @chapter:1 @chapter:36


# Publication Year: 2005
# Title: Fall 2005 G&G Book Reviews
# Abstract: “Shinde Jewels”
By Reema Keswani, 79 pp., illus., publ. by Assouline Publishing, New York, 2004. US$18.95

“The History of Beads: From 30,000 B.C. To the Present”
By Lois Sherr Dubin, 364 pp., illus., publ. by Harry N. Abrams, New York, 2004. US$29.95

“Totems to Turquoise: Native North American Jewelry Arts of the Northwest and Southwest”
Edited by Kari Chalker, Lois S. Dubin, and Peter M. Whiteley, 224 pp., illus., publ. in association with the American Museum of Natural History by Harry N. Abrams, New York, 2004. US$45.00

“Exploration Criteria for Coloured Gemstone Deposits In the Yukon”
By Lori Walton, 184 pp., illus., publ. by the Yukon Geological Survey, Whitehorse, Canada, 2004. C$5.00 (no charge for PDF version). www.geology.gov.yk.ca

“The Pegmatite Mines Known as Palermo”
By Robert W. Whitmore and Robert C. Lawrence Jr., 213 pp., illus., published by The Friends of Palermo Mines, 2004. US$150.00

“Tourmalines of Malkhan”
By V. Ye. Zagorsky, I. S. Peretyazhko, and V. Ye. Kushnaryov, 31 pp., illus., publ. by the Institute of Geochemistry, Russian Academy of Sciences (Siberian Division) and Tourmalkhan Co., Irkutsk, Russia, 2005. US$20.00 (E- mail: victzag@igc.irk.ru)

“Gemstones: Quality and Value, Volume 1”
By Yasukazu Suwa, 143 pp., illus., publ. by Sekai Bunka Publishing, Tokyo (revised English edition), 2005. US$99.95

To view the full section, download the PDF above. @chapter:17 @chapter:0 @chapter:17


# Publication Year: 2021
# Title: James Shigley Receives Robert M. Shipley Award
# Abstract: Dr. James Shigley is the 2021 recipient of the American Gem Society’s Shipley Award. Photo by Kevin Schumacher.

Dr. James E. Shigley, GIA’s distinguished research fellow, has received the American Gem Society’s Robert M. Shipley Award for his significant contribution to the science of gemology. The prestigious award was announced at the AGS Conclave in Dallas on September 13. Dr. Shigley was unable to attend the ceremony but was honored at GIA’s Carlsbad campus by president Susan Jacques, research colleagues, and family, where he was presented with a plaque and pin acknowledging his decades of commitment to gem research.
During his almost 40-year career with the Institute, Shigley has authored or coauthored more than 85 Gems & Gemology articles, edited the G&G In Review book series, and been the face of GIA’s research mission, lecturing extensively on gems and gem identification. He is also the recipient of the 2017 AGS Lifetime Achievement Award. @chapter:21 @chapter:1 @chapter:21


# Publication Year: 2023
# Title: Ethical Supply Chain Practices in Africa with Virtu Gem
# Abstract: Figure 1. Some of Virtu Gem’s larger gemstones from Kenya, Malawi, and Zambia at the Ethical Gem Fair. Clockwise from top: 45.00 ct citrine, 32.33 ct rutilated quartz, 9.80 ct aquamarine, 21.65 ct citrine, 9.99 ct aquamarine, 12.32 ct aquamarine, 17.20 ct aquamarine, and 20.15 ct citrine (center). Photo by Robert Weldon; courtesy of Virtu Gem.
This year marked Tucson’s fourth Ethical Gem Fair, a market cooperative of ten responsibly sourced gemstone suppliers (see Spring 2020 GNI, pp. 177–179). The fair was held January 28–31 at the Scottish Rite Cathedral. Virtu Gem sells gemstones directly from artisanal mining communities in Kenya, Malawi, and Zambia (figure 1) and debuted at the fair in 2022. We spoke with cofounder Susan Wheeler and Percy Maleta, Virtu Gem’s country exporter and ambassador in Malawi, about its beginnings, programs, and impacts.
Wheeler said more new customers come to the Ethical Gem Fair each year. “All the large companies come by, too,” she said. “There were a lot this year that everybody was surprised by. I think that the awareness of what artisanal mining is and what it can be is spreading.”

Figure 2. Artisanal emerald miners in Zambia celebrate a donation by Virtu Gem of safety equipment and a jackhammer. Photo courtesy of Virtu Gem.
Virtu Gem gives artisanal miners, cutters, and traders formal access to international markets and began as a project of Wheeler’s nonprofit Responsible Jewelry Transformative (RJT). Virtu Gem’s programs also offer training in cutting and basic gemology and help miners improve safety, labor, and environmental conditions at the mines, all with a focus on women. Their gemstone prices include a 10% premium that goes toward fulfilling the mining communities’ various needs. During the height of the COVID-19 pandemic, the premium was used for food drives in all three countries and personal protective equipment for Kenyan women miners; currently it goes to the purchase of safety equipment (figure 2).

Figure 3. Left: Virtu Gem cofounders Jessica Hudson, Monica Gichuhi, and Susan Wheeler on a recent visit to Malawi. Right: Percy Maleta, the organization’s country exporter and ambassador in Malawi, examines a rough gemstone. Photos courtesy of Virtu Gem.
Wheeler and cofounders Jessica Hudson and Monica Gichuhi (figure 3) began selling gemstones from Zambia online in 2020, after the pandemic forced the cancellation of a conference they had planned there that would have provided a market for traders. “There was a call to action from the Organisation for Economic and Co-operative Development (OECD) to support all the artisanal miners because no one was coming to the country to buy their stones,” Wheeler said. The OECD’s Call to Action for Responsible Mineral Supply Chains cited COVID-19’s disproportionate impact on artisanal and small-scale miners, who make up more than 80% of the global mining workforce and already face inequities in the supply chain. Wheeler and Hudson are both jewelry designers; Gichuhi is a founding member of the Association for Women in Extractives in Kenya (AWEIK). Her connections with mining associations in Zambia were a starting point.
Beginning in 2021, Virtu Gem received two grants through RJT from the World Bank’s Extractives Global Programmatic Support fund. The fund’s purpose is to promote sustainable and inclusive mining in developing countries and thereby reduce poverty. The grants allowed them to expand into Kenya and Malawi, hold virtual cutting workshops, and implement CRAFT Code in eight mines. (“CRAFT” stands for Code of Risk mitigation for Artisanal and small-scale miners engaging in Formal Trade.) Virtu Gem also hired experienced international consultants.
“There’s been a huge amount of progress over the past two years,” Wheeler said. The funding helped Virtu Gem develop a strong foundation, she said, and grow enough to be able to pass any chain of custody standard for large-capacity buyers.
While Virtu Gem has had success in all three countries, Wheeler said Kenya has seen the most because some in the trade already had Ultra Tec cutting machines and were selling to the international market. “After the first few purchases we did, word spread,” she said. “People were showing up with 50 gems at a time to process.” Miners can also bring gems to the country coordinators for cutting.

Figure 4. Rough tsavorite mined from a site in Kenya. Photo courtesy of Virtu Gem.
Virtu Gem’s gemstones are cut in each country and tracked with Provenance Proof Blockchain. They include amethyst, aquamarine, citrine, moonstone, rhodolite and other garnets, in all three countries; emeralds in Zambia; tsavorite in Kenya (figure 4); and color-change garnet in Malawi. The three countries also produce tourmaline in various colors, including pinkish orange (“sunset”) in Malawi and Zambia and golden in Kenya and Malawi. Production of morganite from newly discovered deposits in northern Malawi recently began.
Virtu Gem has helped miners implement CRAFT Code at four mines in Zambia, two in Malawi, and two in Kenya. CRAFT Code is designed to improve safety, labor, and pay conditions through education at the mines. Its components include mine site certification, safety standards and equipment, and environmental planning, including carbon data tracking and reduction.
CRAFT Code has an emphasis on protecting women, and Wheeler said they focused on women for the associated training. Focusing on woman-owned mines was more difficult, however. “It’s a big challenge for women to own any land at all, especially in Zambia, Kenya, and Malawi,” Maleta said. In Zambia, two of the mines—one emerald and one amethyst—were woman-owned, and in Kenya they worked with a young woman whose family owned a mine.

Figure 5. Artisanal rhodolite miners in Malawi. Photo courtesy of Virtu Gem.
One of Virtu Gem’s benefits is helping artisanal miners formalize their mining process. In Malawi, country coordinator Chiko Manda wanted to focus on rhodolite. Maleta said women account for roughly 80% of rhodolite production there (figure 5). Rhodolite is alluvial and best mined during the rainy season in Malawi, when the women are busy tending their gardens. Virtu Gem worked with a young couple, Ben and Tamara, who did not have a mining certificate.
“The chief of the Chewa people didn’t want the women mining,” Wheeler recalled. “Ben had to go and prove himself to the chief, that he wasn’t going to take advantage, and that the women could still do their agriculture.” Ben joined Virtu Gem’s calls with miners in Kenya and Zambia who shared advice. “He ended up getting permission to mine on the land and the blessing of the chief,” she said. “He sent me on WhatsApp a picture that he had gotten his certificate. He was so happy.” Maleta said that Ben recently received another land permit and is applying for a second mining certificate. “That was a way we could still work with the women,” Wheeler said.
Wheeler mentioned the danger of holding a large amount of gemstones in an informal market, which Ben and Tamara encountered with a quantity of rhodolite. “You have the paradox of the women’s safety,” she said. “Everybody hears about it, and you get all these other dealers and traders coming in. How are they going to get a fair price? Yet they can’t hold on to it.” She said Ben called his friends and pleaded with them to purchase some of the rhodolite. She would like to see a formal system to address this type of scenario.
Maleta said the past four or five years have seen an influx of Kenyans and Zambians to Malawi to buy gems, some of whom export them back home and misrepresent the source country. By exporting directly from Malawi, Virtu Gem has improved supply chain transparency.
Maleta said Virtu Gem pays more than the informal market, but convincing people to participate can be a challenge. “To have someone leave a stone with you and wait—for maybe two months, three months—it hasn’t been easy,” he said. “But we have people who understand the process, who know that the stone they are leaving with Virtu will be sold, but also understand that if it’s not sold, it will be returned. That is trust.”
“I was surprised by the lack of trust at the beginning,” Wheeler said. “We have to work hard to earn the trust from everybody in the gemstone community. We couldn’t have done this without our partner, Monica Gichuhi, working within the communities, and our country coordinators.” She mentioned Caroline Muchira in Kenya, who is also a cutter and a GIA Graduate Gemologist; Manda in Malawi; and Pauline Mundia in Zambia, a respected woman leader whom everyone calls “Mama Pauline.”
“Living up to expectations is hard every single day,” Wheeler said. “Tucson is hard because we don’t own anything on display. Those are people sending us their stones that they’ve invested in. Before, they would have just sold them and not invested in separating parcels and cutting. That’s a lot of pressure. We’ve earned some of that trust, and we really have worked hard to earn that.”
“It’s a dream come true for many to have their stones sold at this level,” Maleta said. “For us, for the country, for the people who are trading, the future is bright.” @chapter:42 @chapter:3 @chapter:42


# Publication Year: 2007
# Title: Natural Type Ia Diamond with Green-Yellow Color Due to Ni-Related Defects
# Abstract: Commonly seen in HPHT-grown synthetic diamonds with a green component, nickel-related defects were identified for the first time in a type Ia natural diamond with a strong green component. The 1.75 ct Fancy green-yellow diamond showed a strong peak at 1332 cm−1 in the IR absorption spectrum, strong absorption from the 1.40 eV center and the associated ~685 nm band in the Vis-NIR spectrum, and extremely strong emissions from Ni-related defects in the photoluminescence spectra—all of which proved that nickel was the primary cause of the green color. @chapter:22 @chapter:1 @chapter:22


# Publication Year: 2023
# Title: Yellow Radiation Halos in Iolite (Cordierite)
# Abstract: Figure 1. A view through the girdle displayed one of the lighter violet pleochroic colors of the iolite host, revealing a mix of monazite and zircon inclusions surrounded by yellow radiation halos. Note the colorless cores in the larger halos. Photomicrograph by Emily Jones; field of view 3.64 mm.

Figure 2. The dark violet background of the iolite shown through a polarizer creates a stunning backdrop for the large apatite and smaller monazite inclusions. The yellow radiation stains surrounding the monazite crystals are much thicker than the thin rim around the apatite. Photomicrograph by Tyler Smith; field of view 1.99 mm.
A mounted violet oval cabochon was recently examined by the authors. The stone was identified as iolite through standard gemological testing and confirmed by Raman spectroscopy. Iolite, the gem-quality variety of the mineral cordierite, (Mg,Fe)2Al3(AlSi5O18), is known for its vibrant coloration and dramatic pleochroism but is rarely the subject of photomicrography because of its tendency to be either clean or heavily fissured. Under the microscope, small colorless and yellow crystal inclusions were observed, most of which were surrounded by yellow halos (figures 1 and 2) reminiscent of blue internal diffusion observed in heat-treated sapphire. Some of the inclusions were identified via Raman spectroscopy as zircon, monazite, and apatite, although not all were reachable due to their size or depth.
Interestingly, the size of the yellow halos varied across the species. For example, the large apatite shown in figure 2 possessed a much thinner halo than the relatively smaller monazites, likely due to the relative concentrations of radioactive trace elements in the inclusions. Alpha particles are known to cause yellow radiation damage in cordierite, both naturally and artificially (R. Krickl et al., “Radio-induced alteration in cordierite—Implications for petrology, gemmology and material science,” Geophysical Research Abstracts, Vol. 11, 2009). This yellow coloration fades at higher levels of radiation, perhaps due to degradation of the crystal structure through a process known as metamictization, which could explain the colorless core displayed by some of the inclusions (figure 1). Inclusions are often used to detect color-altering treatments, making it quite ironic that these inclusions were the source of the alteration. @chapter:15 @chapter:0 @chapter:15


# Publication Year: -
# Title: The Glory of Green Gems
# Abstract: Demantoid garnets provide a field of green for this antique star brooch manufactured in Russia. Demantoid garnets were popular in Russian jewelry from 1875 to 1920. Courtesy of A La Vielle Russie, New York City; photo by Nicholas Del Re © GIA

                      The color green – in all its shades of glory – is the perfect complement to the many colors of flowers that dot our landscapes and the natural settings where we build our homes. It grounds us in nature and reminds us of the cycle of life, symbolizing fertility and growth, as well as freshness and harmony. Green makes us feel safe and rested in a way that few other colors do.

It follows then that green gemstones can uplift and heal our spirits − and have been popular gem choices ever since we began to adorn ourselves with jewelry.

Emerald and jadeite, not surprisingly, come to mind first when thinking of green gemstones. They have held a place of prominence in civilizations since ancient Chinese, Egyptian, Greek and Roman times. In the Chinese culture, jade is considered to be the gemstone of purity and nobility, with the ability to increase vigor and lifespan.

Other green gems include: malachite, maw-sit-sit and peridot.

Gems that come in shades of green include: amber, apatite, Brazilianite, chalcedony (bloodstone and chrysoprase), chrysoberyl (alexandrite), diamond, feldspar, fluorite, andradite garnet (demantoid), grossularite garnet (tsavorite), quartz (aventurine and “greened amethyst”, sapphire, scapolite, serpentine, sphene, spodumene (hiddenite), tourmaline (verdelite, watermelon, cat’s-eye and chrome), turquoise and zircon (beccarite).

Whether you enjoy the many colors of green from the plant world or these exceptional examples of minerals from deep within the earth, these greens are sure to make you feel invigorated!

View Gallery @chapter:40 @chapter:0 @chapter:40