Publication Year: 2015 Title: Oregon Sunstone Update Abstract: Figure 1. Fashioned by lapidary Jean-Noel Soni, this 35.50 ct mixed-cut sunstone is reportedly from a mine on Eagle Butte, in Oregon’s remote Harney Basin. Photo by Robert Weldon/GIA; courtesy of Suncrystal Mining.

At the GJX Show, Nirinjan Khalsa (Suncrystal Mining, Lake and Harney Counties, Oregon) showed us a remarkable 35.50 ct rich orangy red Oregon sunstone fashioned into a modern mixed-cut cushion by lapidary Jean-Noel Soni (Top Notch Faceting). This stone (figure 1) resembled a fine ruby under the showcase lights and was one of the most exquisite examples we had seen.

At Khalsa’s request, we followed up with Soni after the show. He told us the original rough weighed 198.82 ct. As is typical with Oregon sunstone, the rough contained spots of strong red or green color in the cores of otherwise yellow or near-colorless crystals. This crystal had two color spots, so he divided it, and this gem was the first of two he intended to cut. Rather than using CAD software to design his gems’ faceting styles, Soni treats each rough as unique and individual, cutting to maximize color and luster. He explained that the pavilion had to be deep, due to sunstone’s relatively low RI (1.563–1.572). This produced a 63.00 ct preform, from which he faceted the 35.50 ct gem we saw. The asking price for this gem—reportedly from one of the mines on Little Eagle Butte (in Harney Basin, near Plush, Oregon)—was in the region of $60,000.

Also at the GJX show, Don Buford and Mark Shore (Dust Devil Mining, Plush, Oregon) gave an update on their operations. They said 2014 was a good year at Dust Devil. They uncovered a former dried creek bed where the basalt was extensively decomposed, which has allowed easier recovery of the sunstones. Buford hopes to have the mine’s optical sorter operational for the 2015 mining season.

	Dust Devil Mining - “My precious” sunstone

Dust Devil “executive ore relocator” Mark Shore talks about the mine’s current operations. He also proudly displays his new favorite sunstone: a 156 ct “watermelon” crystal he plans to have made into a unique carving.
Shore showed us an exceptional 156.00 ct “watermelon” sunstone from recent production (figure 2). The stone has a red center surrounded by a greenish “rind.” Shore has made arrangements to have it carved by Dalan Hargrave, winner of multiple AGTA Spectrum Awards.

Figure 2. This 156.00 ct rough sunstone belongs to the Dust Devil mine’s Mark Shore and will likely become a fine carving. Photo by Duncan Pay/GIA; courtesy of Mark Shore.
At the 22nd Street show, Terry Clarke, co-owner of the Dust Devil mine, explained a recent initiative to maintain the integrity of natural, untreated Oregon sunstone and promote it to retailers and consumers as a rare and desirable “all-American” gemstone. Called the Oregon Sunstone Miners Association (OSMA), the organization includes most of the miners with working claims or mines in Lake and Harney Counties (figure 3). OSMA also offers an associate membership for sellers of loose gems or jewelry. Anyone purchasing sunstone from an OSMA member can be assured they are getting the natural, untreated Oregon product. The intention is to expand the marketplace for this unique gem and maintain stability and consumer confidence in the event of an influx of treated material from another source. The association’s website is www.oregonsunstonema.com.

Figure 3. Dust Devil Mining’s Terry Clarke holds a flyer promoting the Oregon Sunstone Miners’ Association. Photo by Duncan Pay/GIA; courtesy of Dust Devil Mining.

	Dust Devil Mining

In this interview, Terry Clarke, co-owner and president of Dust Devil Mining, explains the recently established Oregon Sunstone Miners’ Association (OSMA).
At the AGTA show, John Woodmark (Desert Sun Mining & Gems, Depoe Bay, Oregon) provided an update of his operations at the Ponderosa mine and summarized the current market for his goods. He showed us a striking 2.77 ct “spinel red” gem from recent production (figure 4).

Figure 4. This 2.77 ct “spinel red” sunstone, measuring 10.5 × 8 mm, is from Oregon’s Ponderosa mine. Photo by Robert Weldon/GIA; courtesy of Desert Sun Mining & Gems.
According to Woodmark, 2014 saw heightened interest in Oregon sunstone. He received requests for rough from clients in Australia and for finished stones from Brazil and Europe (principally the UK and Germany). At this particular show, Woodmark said he had received many more inquiries from domestic jewelers for samples and information, all following customer requests due to growing public awareness of the gem. He cited a TV shopping channel’s recent promotion of production from the Sunstone Butte mine and the growing reach of his Internet business. For more information on the Sunstone Butte mine, see www.gia.edu/gia-news-research-butte-sunstone.

Woodmark observed that Internet merchandising, often by TV jewelry shopping channels, has been transformative for low-volume, one-of-a-kind products like Oregon sunstone. Web marketing frees traditional TV merchandisers from the production costs of on-air hosts and studios, and allows the cost-effective presentation of a spectrum of Oregon sunstone from “bargain parcels” to unique designer cuts costing several thousands of dollars per piece. According to Woodmark, one buyer for a major TV jewelry retailer at the Tucson shows said that Internet business was now 40% of the company’s total sales volume.

Woodmark estimated the total volume of fashioned Oregon sunstone on the market in 2014 was approximately 70,000 carats. By his calculations, that would be sufficient to supply one large U.S. retail jewelry chain with 10 carats per store per month over the course of a year. If demand picks up in 2015, that volume will not meet the industry’s needs. Woodmark reported that business was up 25% on the previous year’s show, which was up one-third on the year before.

In the 2014 mining season, Woodmark employed up to five pickers working the screens. He worked the mine for a total of 20 days and produced almost 2,000 kg of rough in all grades. Woodmark plans to work for 40 days in 2015 and expects to recover 4,000 to 5,000 kg of rough. To start the upcoming mining season, Woodmark will bring in heavier machinery and extend the pit back into the hillside. He will also bring in a bulldozer with a ripper to tear up the pit floor and start moving downward, too. Late 2014 saw recovery of larger rough, some pieces up to 70 grams (figure 5). In addition, the pit’s “red zone,” with a higher proportion of red-cored rough (up to 20%), remained productive. Woodmark expected the trend of bigger, better stones to continue as the miners work deeper into the deposit. This is similar to the situation at Sunstone Butte, he remarked.

Figure 5. The 2014 season saw some larger rough sunstone from Ponderosa mine in the 20–70 gram range. As operations go deeper, stone size seems to increase. Photo by Duncan Pay/GIA; courtesy of Desert Sun Mining & Gems.
Anticipating higher demand, he also planned to cut more frequently in 2015. Rather than cutting two to three times per year, he will cut 2,000 to 4,000 kg per month (new production plus stockpiled rough), depending on his needs. As 4,000 kg equates to approximately 2,000 carats of finished stones, Woodmark expected his production to significantly increase market availability of Oregon sunstone in 2015.

Like all the Oregon sunstone mines, Ponderosa produces a substantial quantity of yellow and near-colorless labradorite—material with little or no pink or red and no visible coppery reflections. One of the things Woodmark has learned at this show is the importance of cutting style and quality on a gem’s perceived value. He sold 2 kg of yellow rough to another vendor at the AGTA show—Ken Ivey (Ivey Gemstones, Prescott, Arizona)—and was astonished at the result.

Ivey’s use of concave cutting styles (figure 6) presented the feldspar’s bright yellow color far more effectively than conventional cuts. With conventional cutting, Woodmark struggled to get a few tens of dollars per carat for yellow goods. With only a modest investment in extra cutting costs for concave faceting—perhaps twice the expenditure—the same material can sell for up to five times as much. As the yellow rough sells for a couple hundred dollars per kilogram, this is a potentially significant value addition in the finished product.

Figure 6. The concave cutting style used on these Oregon feldspars accentuates their yellow color and raises the market value of the material. Photo by Duncan Pay/GIA; courtesy of Ivey Gemstones.
Another encouraging trend Woodmark sees is that designers and jewelers are mixing calibrated sunstones of different shapes and colors in the same jewelry piece. The casting is standardized, but because every combination is unique there is no longer the need to match them. Volume business with sunstone jewelry has always been hampered by the perception that every stone in a piece has to match and every piece must be uniform.

In Woodmark’s opinion, even home shopping channels like QVC are moving away from that concept, in essence marketing the uniqueness of the gem rather than a uniformity it can never provide. He cited a piece for which he supplied 3.0, 4.0, and 5.0 mm calibrated gems. One was a top-quality red sunstone, and the others were paler pink. In this way, the manufacturer does not have to match the stones and can use larger volumes. @chapter:18


Publication Year: - Title: A Sunstone Odyssey, Part 3: Sunstone Butte Abstract: This  is what Sunstone Butte is famous for: beautiful gems with a winning blend of red and green bodycolor. The larger stone is a significant 23.40 ct, while the smaller example weighs 7.50 ct. Photo by Robert Weldon.

CRYSTALS FROM A CINDER CONE

View Gallery

	Click to view a slideshow of photos from our visit to Oregon’s Sunstone Butte mine.
David Wheatley’s tan is almost a match for the cinder that’s the source of his sunstone. With his partner, Tammy Moreau, Dave is co-owner of the Sunstone Butte mine.

We’ve come out here on the last day of our quest for Oregon sunstone. It’s about a dozen miles or so away from Dust Devil. We’ve already met both owners, as they visited Don and Terry at their mine during our stay. We’ve heard about Sunstone Butte’s large, fabulous sunstones from the other miners and we’re very eager to see them for ourselves.

When we first arrive, Dave is away, helping recover a truck that a mining acquaintance rolled over on one of the nearby dirt roads.

The mine’s camp is a clutch of trailers halfway up the slope of a hill. Blue five-gallon buckets full of feldspar concentrate surround the end of one of the trailers. Another dog—a bigger one called Sheba—barks a welcome.

	David Wheatley is a co-owner of the Sunstone Butte Mine. Photo by Duncan Pay.
Tammy invites us under a shade cover, where she shows us some of the mine’s production. A member of our party picks up a spectacular large rough sunstone with a deep green core. “This changes everything,” he says. There are many similar examples in the tray below: big clean reds, greens, and bicolors. We saw nothing like these at the other mines we visited.

There’s a crunch of gravel as a truck pulls up. Dave is back after helping right the vehicle that rolled over: The driver is OK, but the truck is a wreck.

Pretty soon, we’re standing in a manmade crater under a pure blue sky—the main pit of the Sunstone Butte mine. “It’s a vent, a volcanic vent…much more cinder dome than lava flow,” Dave explains, telling us why his operation is unique compared to other mines in the Rabbit Basin. Rather than mining a relatively thin basalt flow, the operation is excavating the center of a miniature volcano—a cinder cone: “Our pit has four different, distinct layers in it…Geologists have been to all the sunstone mines…I’ve had three or four swing by and they’re in heaven…”

Dave points to the reddish brown rocks exposed in the pit wall and tells us, “The whole side of this hill is just full of sunstones.” He bends down and picks up a bright yellow feldspar from the ground. “The amount of crystal in this pit is just incredible…every rock, just about, has a crystal in it!”

	This large yellow feldspar phenocryst is embedded in a matrix of volcanic cinder. Photo by Robert Weldon.
“What was nice about this area,” he continues, “…I’ve got a little bit of cap rock in this area…A lot of the mines in the valley, you’ve got to go through 10 to 15 or 20 feet of hard rock to get to the ore-bearing flow; this, I could dig with my backhoe.”

Dave mines the core of the hill using a backhoe. He runs the ore through a grizzly—a metal grille—to remove rocks larger than eight inches, which he stores for a later crushing process. The ore smaller than eight inches runs through a small processing plant that removes the loose dirt. Next, they hand-screen the ore on four-by-eight-foot metal-topped tables. Dave and Tammy chose metal surfaces rather than conventional mesh because the rocks roll more easily across the top and the metal reflects the light back up through the feldspar crystals and makes them much easier to spot.

Dave estimates that changing to metal allowed them to recover sunstone at four times the previous rate. Dave does admit that it’s hard work. “Tammy sits here and she does most of the screening…She’ll do this for about eight hours a day.”

Two days of running ore through the grizzly and two days of running the processing plant provides enough material for both to screen for a month. “We’ve put a lot of work and effort into this mine…When we’re up here, we’re mining, pure and simple,” he tells us.

We ask him to tell us what’s so unusual about his mine. “The most unusual thing is the size of our Oregon sunstones,” he responds. “We produce a lot between 100 and 400 to 500 carats.”

It’s not just the size though, he explains, it’s the color too: “About seventy-five percent of our sunstone has green in it, which is one of our rarest colors, and we get a lot of the teal—which is bluish green—very, very rare for sunstone.”

	This large rough sunstone displays a deep green core. Photo by Duncan Pay.
Like the other Rabbit Basin mines, the mining season typically runs from mid-May until early October. “You can push it,” Dave adds. “Last year we stayed until the middle of December…We were digging in the snow for two months, which makes it quite interesting.”

In spite of this mine’s advantages over others in the area, Dave still comes up against the universal character of his profession: “We’ll hit an area, as always with any kind of mining, that’s kind of dead…We don’t get a lot of color, get a lot of clears…But then, just a couple of feet farther, wham! Right back in the color!”

	A Cinder Cone Full of Crystals

	David Wheatley, Sunstone Butte co-owner, introduces us to the heart of the Sunstone Butte mine: an ancient volcanic vent that’s rich in large feldspar crystals.

SUNSTONE BUTTE HISTORY
Dave and Tammy aren’t the only miners who have tried their luck on this hill. Others dug, but found mainly large, clear feldspars, and few colors. They gave up, Dave tells us, “…decided it wasn’t worth it and let go.”

Dave was walking the desert looking for prospects when he found this place. He saw plenty of stones on the surface and noticed that the anthills were full of feldspar. He staked out nine claims in the area. However, because Sunstone Butte is outside the established mining area, he had to wait for a year and a half while the Bureau of Land Management (BLM) undertook a full environmental impact study.

	This view looks down into the main pit. You can judge the scale by comparing it to the trailers in the distance. Photo by Robert Weldon.
Once they started digging, they quickly found some large greens and reds, up to 800 carats, but not in any great quantity. Their luck changed when they switched to the other side of the hill: “We went down five feet and we were starting to hit greens, just green, green, green, green, green, green…of course this is where we’ve been digging since!”

	Sunstone Butte had been open to fee diggers in the past. As Dave and Tammy’s business grew, they cut down on fee digging to concentrate their efforts on more serious mining. Photo by Duncan Pay.

	Why We Dig at Sunstone Butte

	David Wheatley explains why he chose to mine at the Sunstone Butte site.

WHAT DRIVES YOU TO MINE SUNSTONE?
We eventually get to the questions of why mine here, and why this particular gem? “A friend of mine,” Dave answers, “…his dad’s been coming down here for 50 years, and he was coming down to visit him…He was a co-owner in a co-op down in the sunstone valley and I came down with him on a weekend.” Dave was lucky and found a nice red, so his friend’s father faceted it for him.

	This fine 7.70-ct. red sunstone displays broad bars of aventurescent copper particles. Photo by Robert Weldon.
That was the beginning of his fascination with sunstone. He was intrigued by the gem’s varied appearances and visited many of the mines in the area, often paying to be a fee digger.

This experience gave him the intelligence he needed to look for his own claims as well as the confidence to leave his high-paying job at a major corporation and stake it all on sunstone.

	Why I Mine Sunstone

	Miner David Wheatley expresses his passion for sunstone and his love of mining.

PRESENT AND FUTURE SUCCESS
What’s the secret of the operation’s success, we ask? Dave pauses for a moment: “When I was doing fee digging, I analyzed the other miners.” He explains that, while he agrees the mine’s high-quality output is one factor, he wanted to differentiate his gems from everyone else’s: “Most of the miners were doing more basic cutting…As we started getting our volume out here, I decided I wanted to go more high end…We do a lot of concave…linear cuts…we have a designer that’s making new cuts for us…it’s really taken very well out in the marketplace.”

	Working with talented cut designers has paid dividends for Sunstone Butte’s owners by getting their gems noticed in the trade. This innovative cut blends red and green bodycolors. Photo by Robert Weldon.
To bring attention to the mine, Dave adds, he and Tammy participated in a lot of gem and mineral shows—up to 30 a year. Initially, they mounted their stones in simple sterling silver basket settings, but it wasn’t long before they started to work on higher-end products in gold. Eventually, they focused on selling fashioned stones and rough rather than finished jewelry.

Dave sums up the couple’s current approach: “Once you get into jewelry, it takes so much of your time, and we love mining…We’d rather just mine, come out in this beautiful desert and enjoy ourselves mining and take three or four months off!”

	Dave and Tammy work with a number of gemstone cutters and carvers, so they have a wide range of finished gems for sale. Photo by Duncan Pay.
While Dave notes that other sunstone mines—like the Ponderosa—might produce greater volumes of rough, he’s sure that the large sizes and unique green colors his operation produces have made an impact on the market: “We’ve brought the greens and the teals into the market…And all of a sudden it’s a new buzzword, because they’re seeing a different color of sunstone…Instead of one here and one there, they’re seeing a large volume.”

And the couple’s focus on contemporary cutting and carving? “When somebody sees an absolutely breathtaking piece of jewelry, or a carving, it’s a buzz again…word gets out there,” Dave explains. “We’re pretty proud of how we’ve impacted the sunstone industry in the last three years,” he finishes with a smile.

	This fabulous fluted carving displays swathes of the teal-green color that Sunstone Butte is justly known for. Photo by Robert Weldon.

	Marketing Oregon Sunstone

	Sunstone Butte co-owner David Wheatley explains how he and his partner Tammy Moreau went about marketing their mine’s production. @chapter:18


Publication Year: 1981 Title: Lapis-Lazuli from Sar-E-Sang, Badakhshan, Afghanistan Abstract: The lapis-lazuli deposits at Sar-e-Sang in Badakhshan, Afghanistan, have provided the raw material for objects fashioned of this stone since the earliest civilizations. The mine, which lies in the Hindu-Kush Mountains, is difficult to reach and, because of climatic conditions, is opened only a few months during the summer. The lapis is found in veins in which calcite and dolomite are intimately associated with silicates such as diopside, scapolite, and forsterite. Pyrite is always present; the pure blue mineral is lazurite. The color of the lapis-lazuli varies according to the amount of the various impurities contained therein. Well-formed crystals of lazurite with the dominant {110] shape are rarely found. This article examines the crystallographic properties of lapis-lazuli, the site of Sar-e-Sang and the lapis-lazuli deposits there, and offers an explanation for the genesis of the material. @chapter:5


Publication Year: 2015 Title: Fine Tsavorite and Spinel Abstract: Figure 1. This spectacular 12.46 ct tsavorite recently returned to Bruce Bridges’s inventory after being in a collector’s possession for many years. Photo by Robert Weldon/GIA; courtesy of Bridges Tsavorite.

              Bruce Bridges (Bridges Tsavorite, Tucson) said that fine stones often return to his inventory after years in a collector’s possession. At the AGTA show, he showcased a vivid, top-quality 12.46 ct cushion-cut tsavorite fashioned some 15 years earlier, which made its way back into the market in the last two years (figure 1). As tsavorite rough has a high value, gems are typically cut to maximize weight. Rough is typically recovered as long, thin asymmetrical fragments that lend themselves to pear, marquise, and trilliant shapes. This example’s unusual square cushion shape, large size, color, and clarity make it a notable and rare gemstone.

Figure 2. This 18.21 ct Tanzanian red spinel was fashioned from material recovered from one of four enormous multi-kilogram crystals reputedly found in the Ipanko ruby and spinel mining area near Mahenge, Tanzania. Photo by Robert Weldon/GIA; courtesy of Bridges Tsavorite.
After seeing the wealth and variety of gems on display at the Tucson gem shows, it might be easy to come away with the impression that fine colored stones are not particularly rare. Yet the truly magnificent stones are extremely rare and often have a memorable provenance. One such gem is the 18.21 ct triangular cut red spinel Bruce Bridges showed us at his AGTA booth (figure 2). According to Bridges, this magnificent gem was cut in 2007 in Bangkok from rough recovered in one astounding find in Tanzania’s Ipanko mining area that yielded several giant spinel crystals, one of which weighed in at over 50 kg. A number of other dealers at this year’s show, including Axel Henn, also displayed fine gems from this one extraordinary discovery. @chapter:1


Publication Year: 2023 Title: Quarterly Crystal: Columbite(?) in Beryl Abstract: Figure 1. Measuring 26.36 mm in length and weighing 56.00 ct, this Pakistani aquamarine crystal is host to an eye-visible 7.20 mm mineral inclusion cluster. Photo by Annie Haynes.
Those in the gem and mineral community can appreciate the near-perfection of a beautifully crystallized mineral specimen or a well-cut gemstone. But these surfaces are only the exterior, covering a complex, multilayered story within. These internal contents often remain unknown unless we choose to explore below the surface. Somewhat like trees and their rings, minerals and gems form as concentric, typically crystallized layers, recording the developmental details within each layer through changes in temperature, pressure, and chemistry. While some of these growth details are submicroscopic and remain hidden during microscopic observation, other features such as mineral inclusions and encapsulated fluids are waiting to be discovered. In a very real sense, inclusions and their developmental sequencing in their host gems and minerals are descriptions of mineralogical genetics.
Researchers focused specifically on inclusions usually cannot outbid serious gem and mineral collectors for crystals and fashioned gems with interesting internal targets. As a result, many such “gems” end up in private collections, and their inclusions are rarely, if ever, fully documented. This is a tremendous missed opportunity, because inclusions contain geological information that tells a story about themselves and their host.
For this issue’s Quarterly Crystal, we recently had the opportunity to document a well-formed gem-quality, transparent, very light greenish blue terminated hexagonal crystal of aquamarine, with a small amount of light brown matrix at the base and a clearly visible inclusion cluster at the near center (figure 1). The aquamarine was obtained from Muntazir Mehdi of Shad Fine Minerals International in Gilgit-Baltistan, Pakistan. The geographic source was reportedly the Kharguluk mine in Baltistan Province.

Figure 2. None of the analytical techniques at our disposal were able to conclusively identify the mineral making up the 7.20 mm inclusion cluster. The distinctive morphology shown by these inclusions strongly suggests that the cluster is composed of columbite-(Mn) crystals. Photomicrograph by Nathan Renfro; field of view 10.28 mm.
At 56.00 ct with corresponding measurements of 26.36 × 16.09 × 15.02 mm, this aquamarine played host to an easily eye-visible tight cluster of randomly arranged dark reddish brown to black bladed crystals (figure 2) that resembled the mineral columbite-(Mn), Mn2+Nb2O6, as shown by E.J. Gübelin and J.I. Koivula (Photoatlas of Inclusions in Gemstones, Volume 2, Opinio Verlag, Basel, Switzerland, 2005, pp. 263, 319).
Micro-Raman has significantly reduced the time required to instrumentally identify many inclusions. Some inclusion identifications that once took hours can now be made in a matter of minutes using this technique. The Raman instrument can also analyze some subsurface inclusions at depths of more than a millimeter in certain favorable instances, which means inclusions do not need to be exposed to the surface.
After several Raman attempts from different directions, we realized that destructive analysis would be needed to clearly identify the inclusion cluster deep within this stone. Due to the value of this inclusion specimen, we opted to forgo destructive analysis and keep the beryl crystal intact for future gemological exploration. @chapter:4


Publication Year: - Title: Ametrine Quality Factors Abstract: The best ametrines show distinct areas of orangy yellow and purple. These colors are featured in this graceful cut design. Photo by Lydia Dyer, © John Dyer & Co., gem courtesy John Dyer & Co.

                      When Bolivia’s ametrine mine reopened in the 1960s after being lost for centuries, the gem’s bicolor appearance became popular with dealers and gem designers. Its colors range from pale to intense amethyst and citrine shades.

	The rough output from the Anahi mine produces amethyst, citrine, and ametrine finished
	gems in a range of tone and color intensities. Photo © GIA and Tino Hammid.
Color
Fine ametrine shows medium dark to moderately strong orange, and vivid to strong purple or violetish purple. Larger gems, usually those over five carats, tend to show the most intensely saturated hues. Dealers look for an attractive half-and-half distribution of each color, with a sharp boundary between the two colors at the center of the fashioned gemstone.

	Rectangular cuts show off ametrine’s unique appearance. Photo by Robert Weldon/GIA, courtesy Cynthia Renee Co.
Cut
Connoisseurs prize imaginative designer cuts that display ametrine’s two colors in artfully blended or contrasting combinations.

	This 48.50-ct. ametrine, fashioned by gem designer Dalan Hargrave, dazzles the eye. Photo by Robert Weldon/GIA, courtesy Minerales y Metales del Oriente, Bolivia, SA.
Clarity
Much of the faceted ametrine in the market is eye-clean, meaning it lacks eye-visible inclusions.

	Like most faceted ametrine, this bicolor rectangular step cut has no eye-visible inclusions. Photo by Van Rossen, © ICA, courtesy Columbia Gem House.
Carat Weight
When it comes to highly prized ametrine, size matters. That’s because the best, most intense citrine and amethyst colors are found in larger sizes, usually over 5 carats.

	This 87.66-ct. ametrine displays the rich purple of amethyst along with the contrasting orangy yellow of citrine. Photo by Robert Weldon/GIA, courtesy Minerales y Metales del Oriente, Bolivia, SA. @chapter:2


Publication Year: - Title: Jewels of Hollywood: Accessories and Jewelry that Made the Stars Shine Abstract: This diamond and emerald brooch set in platinum, which belonged to Faye Dunaway, contains approximately 15 cts of diamonds and 5 cts of emeralds. Courtesy of the Kazanjian Foundation’s Hollywood Collection. Photo by Orasa Weldon/GIA

Our fascination with celebrities – and their glittering jewels, accoutrements and couture clothing – has fed our imaginations since the early days of motion pictures. They represent who we think we could be in our wildest dreams.
Hollywood – and the jewels stars wear – have gone hand-in-hand for many years to attract the attention and imagination of movie-going audiences. The Golden Age of Hollywood, roughly from the end of silent movies through the 1950s and 60s, was flush with funds and a studio system that produced glittering and glamorous stars and moneymaking films.

Actress Mary Pickford's sterling silver clutch was a gift from her actor/musician husband Charles "Buddy" Rogers. Courtesy of the Kazanjian Foundation’s Hollywood Collection. Photo by Orasa Weldon/GIA
Once a potential leading lady was found, a team set about to transform her into a star, according to “Hollywood Jewels: Movies, Jewelry, Stars,” written by Penny Prodow, Debra Healy and Marion Fasel. This included developing her look, her home and her social life.
“With so much money tied up in a star, decking her out in precious jewelry was considered not an extravagance but part of the investment,” according to the book.
“Jewels of Hollywood,” on loan from the Kazanjian Foundation, showcases some of the pieces associated with Hollywood royalty of decades past. It is a window into the lives and loves of some of the entertainment industry’s most iconic members.

There are several sets of cufflinks on display, including signer/actor Bing Crosby’s, left, and comedian/actor Bob Hope’s. Crosby’s gold cufflinks are lyrically scrolled with his first name. Hope’s 14K yellow gold cufflinks are engraved "TO ROBERT" on one cufflink and "XMAS 1972 BOB HOPE" on the second. Courtesy of the Kazanjian Foundation’s Hollywood Collection. Crosby photo by Orasa Weldon/GIA. Hope photo by Emily Lane/GIA
Arranged by topic, the exhibit cases include jewelry, cufflinks and other accessories, such as watches, compacts, cigarette cases, money clips and mesh handbags. The stars and movie moguls represented include:

Leading Men – Clark Gable, Danny Kaye, Bing Crosby, Bob Hope Dean Martin, Buddy Hackett and Jack Benny.
Leading Ladies – Eva Gabor, Gloria Swanson, Mary Pickford, Shirley Temple, Mary Ann Mobley, Joan Collins, Martha Scott, Faye Dunaway and Madonna.
Behind the Scenes – Billionaire businessman producer Howard Hughes, writer and director Billy Wilder, and producer and co-founder of Twentieth Century Studios (later 20th Century Fox) Darryl F. Zanuck. The case also contains pieces by some of America’s titan families, including the Duponts and J.P. Morgan.

What is striking about many of the pieces in this collection is that they were actually picked out and owned by the stars, not selected by stylists, as is common today, says Terri Ottaway, curator of collections for the GIA Museum in Carlsbad, California.
“Jewelry is one of the most sentimental objects we can buy for ourselves or as gifts for others – and movie stars love sentimental gifts just like the rest of us,” she says. “A lot of these pieces have inscriptions that are really endearing.”

Actor Clark Gable gave this gold compact case, circa 1930s, to his third wife, actress Carole Lombard. Rubies, sapphires, demantoid garnets and diamonds frame the initials "LG" (Lombard and Gable). Courtesy of the Kazanjian Foundation’s Hollywood Collection. Photo by Orasa Weldon/GIA
Carole Lombard, for example, gave a beautiful gold cigarette case to her husband Clark Gable with the engraving: “Darling” with love from “Ma,” dated “Xmas 41,” referencing the pet names “Ma” and “Pa” Lombard and Gable called each other.
Also included in the exhibit are some of the compacts and cases stars used to carry makeup and other items.

Actress Eva Gabor’s gold compact is embellished with synthetic rubies. Courtesy of the Kazanjian Foundation’s Hollywood Collection. Photo by Orasa Weldon/GIA
“When the stars used to travel, there wasn’t a traveling jewelry box type of item to keep their baubles and personal items secure, so it wasn’t uncommon to see a grand dame using an old cigar box, or coffee can, or tobacco tin, or something along those lines to hold her jewels and makeup,” says Doug Hall, an instructor at GIA.
Soon, iconic jewelry houses, such as Van Cleef & Arpels, responded by creating elegant compacts to hold these items, he says. The cases could be personalized and embellished with gemstones and motifs.
The exhibit includes Eva Gabor’s ruby-embellished lipstick case, compact and notebook holder from Van Cleef & Arpels and compacts from Mary Pickford and Gloria Swanson.

Actress Martha Scott wore this star ruby and diamond ring set in platinum at the premiere of her movie “Hi Diddle Diddle” in 1943. Scott also appeared in such blockbusters as “The Ten Commandments” and “Ben Hur” and received an Academy Award nomination for “Our Town.” Courtesy of the Kazanjian Foundation’s Hollywood Collection. Photo by Orasa Weldon/GIA
Fans of The Golden Age of Hollywood will enjoy seeing “Jewels of Hollywood” as they tour GIA, says Ottaway.
“It’s an extra-special treat for older visitors and fans of old movies,” she says. “There is something wonderful about being able to make a personal connection with the iconic stars you remember seeing on the big screen.” @chapter:16


Publication Year: 2017 Title: Gota de Aceite in a Zambian Emerald Abstract: A muted gota de aceite effect, with epigenetic ilmenite, in an emerald from Zambia. Photo by Nathan Renfro; field of view 1.26 mm.

Gota de aceite (Spanish for “drop of oil”), a rare phenomenon that occurs in the finest emeralds, is typically associated with Colombian origin (R. Ringsrud, “Gota de aceite: Nomenclature for the finest Colombian emeralds,” Fall 2008 G&G, pp. 242–245). The phenomenon creates a roiled effect caused by irregularity in the emerald’s internal crystal structure. During the gemstone’s crystallization the growth conditions are altered, giving rise to rapid columnar growth. When looking down the emerald’s c-axis, the outline of the columns can be seen. This sometimes has the appearance of drops of oil, giving rise to the name. The columns typically have a slightly different trace element composition from that of the host emerald. This heterogeneity in trace element chemistry will cause a minor change in the refractive index of the columns, allowing the structure to be visible.

The Carlsbad laboratory recently received a 2.10 ct emerald for origin determination. The stone had blocky multiphase inclusions and ilmenite scattered throughout, along with mica platelets and a very subtle blue flash effect associated with some small feathers. At a certain angle, a muted gota de aceite effect was also visible (see above). The UV-Vis spectrum shows a distinct Fe2+ broad band at approximately 900 nm. Inductively coupled plasma–mass spectrometry (ICP-MS) confirmed the stone’s relatively high iron content and indicated a chemical composition consistent with Zambian origin.

The gota de aceite seen in this Zambian emerald was not exactly the same as the phenomenon found in Colombian emeralds. Dendritic ilmenite, an iron-rich mineral, was fully enclosed in the columnar structure. We believe the epigenetic ilmenite exsolved the increased iron content, as Zambian emeralds contain a larger amount of iron than their Colombian counterparts (J.C. Zwaan et al., “Emeralds from the Kafubu area, Zambia,” Summer 2005 G&G, pp. 116–148).

Until now, gota de aceite has only been documented in Colombian emeralds and has been an aid in origin determination. Still, this is not the first time that an inclusion indicative of a particular origin has been found elsewhere. Jagged three-phase inclusions, traditionally seen in Colombian emeralds, have also been documented in emeralds from certain mines in Afghanistan, China, and Zambia (S. Saeseaw et al., “Three-phase inclusions in emerald and their impact on origin determination,” Summer 2014 G&G, pp. 114–132). This emerald shows that inclusions may not always provide conclusive proof of origin, but they can still provide useful information. @chapter:6


Publication Year: 2021 Title: Iridescent Botryoidal Growth in Untreated Akoya Pearl Abstract: Iridescent and botryoidal subsurface growth seen in a pair of untreated akoya pearls. Note the nacre lines visible at the surface (top right of image B), giving context to the unusual growth and phenomenon below the surface. Photomicrographs by Britni LeCroy; field of view 3.57 (A) and 2.34 mm (B).
Cultured akoya pearls (Pinctada fucata) are typically admired for their high luster and desirable overtone. Nearly all pearls from this species undergo color treatment before entering the market. One untreated akoya pearl examined by the author exhibited an iridescent and botryoidal subsurface appearance when viewed with a fiber-optic light under microscopic magnification (see above). This was in sharp contrast to the pearl’s appearance without magnification, which showed a light gray bodycolor and smooth surface.
The light gray bodycolor of the pearl was caused by large voids or gaps surrounding its bead nucleus, which could be seen using real-time X-ray microradiography (RTX). Akoya pearls possess very thin nacre platelets that are transparent to translucent when viewed under strong lighting, allowing the viewer to see into the deeper layers of the pearl. The strong iridescence was caused by light interference within alternating layers of aragonite and conchiolin—the two substances that create nacreous pearls and that also have different refractive indices. Specifically, this iridescence is caused when incoming overhead light is reflected from the surfaces between the successive aragonite and conchiolin layers. When the reflected light rays from a bottom layer of nacre interfere with the incoming light, iridescence is created. In pearls, this feature is known as orient (E. Fritsch and G.R. Rossman, “An update on color in gems. Part 3: Colors caused by band gaps and physical phenomena,” Summer 1988 G&G, pp. 81–102). The underlying botryoidal structure combined with the iridescence from the overlying nacre was responsible for the unusual pattern or orient seen in this akoya pearl. This is the first time the author has encountered such a phenomenon in a pearl. @chapter:14


Publication Year: 2015 Title: Natural Faceted Red Rutile Abstract: Figure 1. The 4.40 ct natural red rutile on the left was compared with a 4.47 ct orange flame-fusion synthetic rutile. Photo by C.D. Mengason.

	The Carlsbad laboratory recently received a 4.40 ct dark red marquise brilliant (figure 1, left) for examination. Standard gemological testing revealed a refractive index that was over the limit of the RI liquid, as well as a hydrostatic specific gravity of 4.27. The specimen was inert to both long-wave and short-wave UV. Under reflected light, it showed a metallic luster. Raman testing identified the material as rutile. To distinguish it as natural or synthetic rutile, we compared it with a known flame-fusion orange synthetic rutile sample (figure 1, right).

Figure 2. In this natural red rutile, an octagonal blockage is capped at the end of the growth tube. Photomicrograph by Ziyin Sun; field of view 1.40 mm.

	Under magnification, the most distinctive internal characteristic of the dark red specimen was an octagonal blockage with a long growth tube extending to the surface (figure 2). Near the girdle, some unknown rectangular tabular inclusions were also observed, which were not identified by Raman spectroscopy (figure 3). Both internal features indicated the specimen was natural rutile. Straight and angular growth banding was also observed (figure 4). Raman spectroscopy for both the red sample and the orange synthetic revealed major peaks at 610, 446, and 242 cm–1 and minor peaks at 818, 707, and 319 cm–1, confirming their identity as rutile (see the RRUFF database at rruff.info).

Figure 3. Near the girdle, rectangular tabular inclusions are observed under fiber-optic illumination. Photomicrograph by Ziyin Sun; field of view 2.43 mm.

Figure 4. The natural rutile shows straight and angular growth banding. Photomicrograph by Ziyin Sun; field of view 4.92 mm.

	Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) revealed that the dark red rutile had a composition of 98.2% TiO2 and 1.5% Fe2O3 by weight, with traces of Mg, Al, Si, Ca, Sc, V, Cr, Cu, Zn, Zr, Nb, Cd, In, Sn, Sb, Hf, Ta, W, Pb, and U. The presence of Nb (176.81–296.93 ppmw), Ta (15.13–25.81 ppmw), Hf (0.15–0.40 ppmw), Zr (3.29–4.84 ppmw), Pb (0.01–0.56 ppmw), and U (0.07–0.27 ppmw) suggested a natural origin. The orange synthetic rutile contained 99.9% TiO2, plus traces of Mg, Si, Cr, Co, Cu, and Zn. Traces of iron (1.66 ppmw, 0.0238% Fe2O3 by weight) were also detected. Synthetic rutile boules created by the Verneuil process have an orange color with 0.04% Fe2O3 and a clear reddish color with 0.2% Fe2O3 (C.H. Moore, Jr. and R. Dahlstrom, “Synthetic rutile crystal and method for making same,” U.S. Patent 2792287). The red specimen’s lower chemical purity indicates natural origin.

	Visible spectra of both stones were taken. The red bodycolor of the natural rutile matched the transmission window between 650 and 700 nm in the red portion of the spectrum, which was likely caused by iron.

	Although rutile is a common inclusion in many minerals, the few crystals that are faceted usually weigh less than 1 ct. This faceted stone was very rare because of its large size. It was the first faceted natural rutile examined by GIA’s Carlsbad laboratory. @chapter:19


Publication Year: - Title: GIA Scholarship Helps Designer Build Technical Skills, Creativity Abstract: Wisner’s final project for his JDT class at GIA was this 18K yellow gold, emerald and lariat suite. The green is a vitreous transparent enamel, and the lariat features a 30-ct, round brilliant emerald. “This suite is one of my greatest prides as a designer,” Wisner says. “I used everything I had ever learned in making it.” Courtesy of Daniel Wisner.

Daniel Wisner’s pulse quickened as he walked down the hallway with his mother to pick up his older brother from metalsmithing class. The closer they got, the louder the strains of Black Sabbath and rhythmically clanging hammers echoed down the hallway. The wide-eyed 9-year-old entered the arts center classroom and was immediately captivated.

“People were hunched over mandrills and forming stakes, hammering away at silver bowls, while my brother, Justin, was in the corner with a blow torch and massive, Mad Max-style goggles shielding his face,” remembers Wisner, a GIA Jewelry Design and Technology (JDT) graduate and co-owner of Brooklyn jewelry design firm Matthias & Wisner. “The instructor stood front and center, hair past her waist, encrusted in silver from head to toe. I immediately felt at home in the metal shop and from that point on, I wanted to be a jeweler.”

Wisner anxiously waited for his 11th birthday when he could join his brother in an apprenticeship with the instructor, silversmith Kristen Alice Urffer. The brothers studied alongside Urffer for the next five years.

“Kristen did things the old way, and really drove home the ‘practice makes perfect’ maxim,” he says. “She instilled in us patience and dedication to the craft. Her focus and ‘do it again’ mentality gave me the backbone to continue in the industry.”

Daniel Wisner, JDT, has a diverse artistic background including sculpture and performance art, though jewelry has been his focus since an apprenticeship with a silversmith at just 11 years old. Wisner operates the Brooklyn-based design firm, Matthias & Wisner, with his brother, Justin. Courtesy of Daniel Wisner.
Wisner then apprenticed with a production jeweler before heading to Kutztown University of Pennsylvania to earn his Bachelor of Fine Arts in Enamel and Jewelry Arts. While there, he worked as a studio monitor in the school’s metal and jewelry arts program and began a small business creating commissioned jewelry pieces.

He graduated from Kutztown in 2014 and was awarded a residency and yearlong staff artist position at the Vermont Studio Center (VSC) in Johnson, Vermont. As the end of Wisner’s year of experimenting with sculpture, performance art, and his longtime favorite – jewelry design – at VSC drew near, he began to explore work as a designer in New York City. He was soon hit with an uncomfortable reality.

“I quickly found that while my artistic skills were on par with industry expectations, my technical knowledge was lacking,” he says. “I’d spent years working on techniques that were no longer used industry-wide. Though I knew how to talk to a jeweler about making a three-stone engagement ring with a cathedral setting and could show them a sketch, I didn’t know how to produce it in CAD – or even what CAD was.”

After one disappointing job-hunting trip, Wisner remembered that another mentor, jeweler Janna Gregonis, had told him about GIA and how it could give him an “unparalleled education” and “a better edge against competition in the job market.” He did some research and was surprised to learn that GIA offered a seven-month intensive program in Carlsbad on CAD and design. He applied to the program and for a scholarship the next day.

A few months later, Wisner received a letter stating he had received the scholarship in whole.

“I could barely speak,” he says. “I knew from that moment that my life just made a major shift.”

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That life change was dramatic: Wisner moved from the East Coast to Southern California in 2016. His brother Justin, who had also trained as a jeweler and blacksmith and was working in jewelry sales, moved with him to help support him while he threw himself into the intensive program. Wisner attended every student lecture, checked out stacks of books at the “second-to-none” Richard T. Liddicoat Gemological Library and Information Center almost daily, and focused on showing up every time.

“These classes are grueling and long, filled with painstaking detail and work, but that’s exactly why you should come to class every single day,” he says. “So much happens in one day, it can set you back more than you think just by missing even an hour.”

Wisner clearly remembers a day in class when he was “mesmerized” by the “absurd levels of detail” he and his classmates learned to create a piece of jewelry in Matrix. His instructor told him it was “just the beginning” of what was to come in technology.

“At the time I couldn’t believe that CAD could get any more advanced than what I’d just experienced, but now I know how right he was,” Wisner says. “The JDT program prepared me to enter the industry as a technical designer and gave me the tools and knowledge I needed to get started.

“I learned more in seven months about technology, stone grading and business practices than I ever thought possible, and my base of knowledge is more expansive than I ever hoped. I feel more confident and in control of my work than ever before and know that I’m able to create exactly what I’ve drawn on paper using the knowledge I gained during my time at GIA.”

The Wisner family – from left, mother Lydia, Daniel, Justin and father Peter – celebrate Daniel Wisner’s 2017 graduation at GIA in Carlsbad. “The community one can create while attending GIA is without a doubt a cornerstone to building a successful career as a jeweler, designer, gemologist or business owner,” Wisner says. “The people I met during my time at GIA have become my support group and lifeline for how to navigate the industry.” Wisner and his brother often source stones for their design house, Matthias & Wisner, through friends he met at GIA. Courtesy of Daniel Wisner.
Wisner’s hard work paid off – within six months he had a full-time job as an assistant technical designer at Alexis Bittar. Though his own company was successful, he felt it was important to work for and with other professionals.

He also continues to operate Matthias & Wisner – homage to his parents’ surnames – with his brother. They create commissioned jewelry together, and Wisner says their work complements each other.

“I tend to focus on the stones, and Justin is more metal-focused,” Wisner explains. “And I hold fast to some of the ‘rules’ of design, while Justin’s organic design background frees him of that cage. Our aesthetics are quite similar, though, and we both have classic taste, focusing on using the best materials and creating timeless profiles. This leads to a harmony of contemporary classics.”

They’re both avid students of history and distance themselves from trends in favor of comfortable, wearable jewelry and lasting style, looking to “the greats” like Audrey Hepburn, Steve McQueen, Jackie Onassis and David Bowie for inspiration.

“This piece is super-fun,” Wisner says. “It’s a two-piece construction that allows the owner to put anything they want inside the ‘cage’ prior to completion, from a pearl to a rough stone to a memorial object. The ‘cage’ is then laser-welded together to ensure the object’s safety.” Courtesy of Matthias & Wisner.
“Style is inherently personal,” Wisner says. “Learning how to interpret style gives someone the key to learning how to design what a client really wants.”

As the brothers look forward to growing the business and create a new line of jewelry, Wisner has no plans to stop learning.

“Technique and technology are crucial to successful design,” he says. “Staying current with technology in our industry allows for new possibilities within design – when we stop being restricted by possibility and are allowed to express ourselves, we can create without concern. That’s why I attended GIA, and why I continue to push for development today. Our industry grows every day, and with it, so should we.” @chapter:36


Publication Year: 2007 Title: Spring 2007 G&G Book Reviews Abstract: “Pearls”
By Elisabeth Strack, 678 pp., illus., publ. by Rühle-Diebener-Verlag, Stuttgart, Germany, 2006. C= 106.10 (US$115.00)

“Not Your Mama’s Beading: The Cool and Creative Way to String ‘Em Along”
By Kate Shoup Welsh, 224 pp., illus., publ. by Wiley Publishing [www.wiley.com], Hoboken, NJ, 2006. US$14.99

“Special Exhibition Jadeite: Treasure of Orient”
By the National Science Museum [www.kahaku.go.jp/english], 202 pp., illus., publ. by the Mainichi Newspapers Co., Tokyo, 2004 [in Japanese; no price information available]

“Hope Diamond: The Legendary History of a Cursed Gem”
By Richard Kurin, 388 pp., illus., publ. by Smithsonian Books [www.smithsonianstore.com], Washington, DC, 2006. $24.95

“Precious Minerals (Gemology)”
By Ruslan I. Kostov, 453 pp., illus., publ. by PENSOFT [www.pensoft.net], Sofia, Bulgaria, 2003 [in Bulgarian; no price information available]

“Faceting History: Cutting Diamonds and Colored Stones”
By Glenn Klein, 242 pp., illus., publ. by the author [www.glennklein.com], Lake Forest, CA, 2005, US$21.99

“Symposium on Agate and Crypto- crystalline Quartz”
Daniel Kile, Thomas Michalski, and Peter Modreski, Eds., 144 pp., illus., publ. by Friends of Mineralogy (Colorado Chapter), Colorado School of Mines Geology Museum, and U.S. Geological Survey, 2005, US$20.00

“The Art of Diamond Cutting, 2nd ed.”
By Sofus S. Michelsen and Basil Watermeyer, 147 pp., illus., publ. by Sofus S. Michelsen [sofus_sidney@ direcway.com], Port Angeles, WA, 2005, US$49.95

“Alexandrite”
By Yury S. Kozlov, 143 pp., illus., publ. by Nauka Publishers [www.maik.rssi.ru], Moscow, 2005, C= 33.00

Aphrodite’s Drop: The Power of Pearls”
A Faction Films production [www.factionfilms.co.uk], London, 75 min., 2005, available in DVD format, £30.00

To view the full section, download the PDF above. @chapter:25


Publication Year: - Title: Citrine Description Abstract: Citrine is one of the most popular yellow gems on the market. This designer cut shows off the warm glow of citrine’s sunny color. – Lydia Dyer, gem courtesy John Dyer & Co.

                      Citrine—the transparent, pale yellow to brownish orange variety of quartz—is rare in nature. In the days before modern gemology, its tawny color caused it to be confused with topaz. Citrine’s attractive color, plus the durability and affordability it shares with most other quartzes, makes it the top-selling yellow-to-orange gem. It’s an attractive alternative not only for topaz, but also for yellow sapphire. The finest citrine color is a saturated yellow to reddish orange free of brownish tints.

	These gems, ranging from orangy yellow to reddish orange, are examples of fine citrine color. - Courtesy C. Y. Sheng
Since natural citrine is rare, most of the citrine on the market is the result of heat treatment, which causes some amethyst to change color from undesirable pale violet to an attractive yellow. The amethyst’s original hue can determine the richness of the resulting citrine’s yellow color.

	Low-temperature heat treatment transformed an amethyst into this orangy citrine. A gem carver created the attractive fantasy cut. - GIA & Tino Hammid
Citrine crystals occur in a wide range of sizes, and citrine sizes up to 20 carats are readily available in jewelry. Although citrine is available in standard shapes and sizes, many high-end jewelry designers and gem carvers have fashioned the warm yellow gem into unusual cuts for jewelry and carvings.

	This citrine carving weighs 167.78 carats. - Courtesy ICA @chapter:20


Publication Year: 2019 Title: Resin Imitation Ivory with a Pseudo “Engine-Turned” Structure Abstract: Figure 1. Left: Material A, 24.40 mm in diameter and sold under the name “Arvorin Plus,” shows parallel linear striations along its length and unorganized perpendicular striations along the horizontal plane. Right: Material B, 18.93 mm in diameter and marketed as “Resin-Ivory+S,” exhibits parallel linear striations along its length and perpendicular striations with an average angle of 90° along its horizontal plane. Photo by Dylan Hand.

Resin materials marketed as imitation ivory were recently acquired by a GIA gemologist. Material A, marketed under the name “Arvorin Plus,” was purchased from a billiard store. Material B, sold as “Resin-Ivory+S,” was purchased from a guitar store. These are manufactured as rods that can be purchased in a variety of lengths. Both show fine parallel linear striations along their length and a distinct pattern reminiscent of Schreger lines, commonly referred to as an “engine-turned” effect, when viewed across their horizontal plane (figure 1). These are also characteristics seen in genuine elephant and mammoth ivory.
The resin materials were found to have nearly identical gemological properties. Both had a Mohs hardness around 2, indented when pressed firmly with a pointer probe, and melted rapidly when touched with a hot point. They also had a spot refractive index reading of 1.57, a hydrostatic specific gravity of 1.24, and were inert to long-wave and short-wave ultraviolet light. Raman spectroscopy further confirmed their identity as a polymer substance.

Figure 2. Left: Elephant ivory with Schreger lines intersecting at an average angle of 109°; field of view 19.27 mm. GIA Collection no. 4287. Right: Mammoth ivory with Schreger lines intersecting at an average angle of 69°; field of view 19.27 mm. Part of GIA Collection no. 19267, donated in 1995 by Richard Marcus of Mammoth Enterprises, Inc. Photos by Dylan Hand and Britni LeCroy.
Genuine elephant and mammoth ivory typically show a refractive index of 1.540, a specific gravity between 1.70 and 2.00, and weak white to blue fluorescence under both long-wave and short-wave UV. Ivory’s most distinguishing characteristic is a display of Schreger lines (“engine turning”), an inherent growth property that is visible when specimens are cut perpendicular to the length of the tusk. These Schreger lines create unique angles that distinguish between mammoth and elephant species. When concave angles that open to the inner area of the tusk are measured, mammoth ivory will show an average angle of less than 90°, while elephant ivory will show an average angle greater than 90°. Figure 2 shows elephant and mammoth specimens oriented with their concave angles opening to the inner area of the tusk. Their Schreger lines intersect at average angles of 109° and 69°, respectively. These can be compared to materials A and B. While material A did show perpendicular striations along the horizontal plane, the angles were not particularly organized or consistently measurable. However, material B had “engine-turned” striations at an average angle of 90° along this same plane.

Figure 3. Three ivory imitations carved for this study. The tusk (52.23 ct) and the cabochon on the right (35.37 ct) were created from material A. The cabochon on the left (14.67 ct) was created from material B. Photo and lapidary by Dylan Hand.
Cabochons were cut from both types of resin, and the form of a small elephant tusk was carved out of material A (figure 3). The resins’ low hardness allowed them to be quickly ground down for shaping, while their high toughness prevented any chipping or fracturing even on small details. The resins each consist of two components with slightly different hardness, which produces the engine-turned pattern. One difficulty is that when attempting to shape a smooth surface, the darker and lighter areas erode at different speeds, creating an uneven texture. This effect is minimized, though, at the prepolishing stage of the carving. The low melting point of the ivory imitations posed an added challenge during the polishing process. When attempting to polish with a compound applied to a felt wheel, the resins can melt and deform relatively quickly.
Elephant ivory was first regulated under the Endangered Species Act in 1976, with more recent laws creating a near-total ban on its import and export. Laws regarding mammoth ivory vary by state. Ivory imitations are now commonly used in their place for furniture and musical instrument inlays, jewelry, and various accessories. Both resins are purportedly composed of spun polyester and are being produced in China. @chapter:37


Publication Year: - Title: Fall 2019 G&G: Gem Art of the Taj Mahal, Fancy White and Black Diamonds, and Unique Inclusions in Thai Corundum Abstract: The Fall 2019 edition of Gems & Gemology opens with a look at the rich gem history of the Mughal dynasty and the intricate gem inlay work of the Taj Mahal. The issue also features an investigation into the cause of color in Fancy white and Fancy black diamonds, mineral inclusions in corundum from the Bo Welu deposit in Thailand, characteristics of hydrothermally treated amber, and more.
Gemstones in the Era of the Taj Mahal and the Mughals
The lead article, by Dona Mary Dirlam and co-authors, looks back to the seventeenth century and the Mughal dynasty that ruled much of India. The Mughals collected extraordinary jewelry and gems and transported these riches across intricate trade routes. Emperor Shah Jahan commissioned the building of the iconic Taj Mahal, which features elaborate decorative parchin kari inlay of ornamental and fine gems.
Natural-Color Fancy White and Fancy Black Diamonds: Where Color and Clarity Converge
Sally Eaton-Magaña and Christopher M. Breeding continue their series of colored diamond characterization studies with a look at Fancy white and Fancy black diamonds. These two colors are distinctive for their cause of color: nanometer- to micrometer-sized inclusions that reduce the diamond’s transparency, rather than atomic-scale defects typical of other fancy-color diamonds.
Unique Vanadium-Rich Emerald from Malipo, China
Yang Hu and Ren Lu provide an overview of the history, resource potential, and geology for emeralds from Malipo County in southwestern China. Malipo emerald has unique multiphase inclusions and a distinct chemical composition that helps separate it from other deposits.
Mineral Inclusions in Ruby and Sapphire from the Bo Welu Gem Deposit in Chanthaburi, Thailand
Supparat Promwongnan and Chakkaphan Sutthirat discuss the various mineral inclusions observed in Bo Welu ruby and sapphire. Some newly reported mineral inclusions in Thai corundum—sillimanite, nepheline, quartz, alkali feldspar, spinel, and anhydrite for ruby and purple sapphire, and sulfide for blue sapphire—can be used to support origin determination.
Characteristics of Hydrothermally Treated Beeswax Amber
Hydrothermal treatment optimizes the appearance of semi-translucent to opaque “beeswax” amber and expands the availability of amber products. Yamei Wang and co-authors explore the characteristics of hydrothermally treated beeswax amber to assist with identification challenges.
Effects of Mollusk Size on Growth and Color of Cultured Half-Pearls from Phuket, Thailand
In order to find ways to increase the overall production and value of cultured half-pearls, Kannika Kanjanachatree and a team of researchers studied 400 Pteria penguin mollusks over a period of 10 months. They set out to determine the optimum mollusk size, compare rejection and mortality rates, and chart the color and quality of cultured half-pearl samples from month to month. Their findings have important consequences for color-matching of half-pearls.
Hydrogen-Rich Green Diamond Color-Treated by Multi-Step Processing
Identifying the color origin of green diamonds is sometimes difficult for gemological laboratories. In this article, Wenqing Huang and co-authors propose two alternative multi-step treatment procedures that would explain the combination of spectroscopic features observed in a 0.25 ct color-treated yellowish green diamond.
Pressed Gibbsite and Calcite as a Rhodochrosite Imitation
Hanyue Xu and Xiaoyan Yu investigate the differences between rhodochrosite and a new rhodochrosite imitation that has recently appeared in the market. Standard gemological testing can identify the imitations, which are composed of pressed gibbsite and calcite powder with a granular structure.
Lab Notes
GIA laboratory staff members present their latest findings in the Lab Notes section, including a star-shaped cloud inclusion in a faceted diamond, new resin imitations of ivory, and a cobalt-coated sapphire.
Micro-World
The Micro-World section, dedicated to the inner world of gemstones, features a rain cloud in alexandrite, an intergrowth of iolite and sunstone, and an abundance of pyrite inclusions in dravite from Mozambique.
Gem News International
Finally, GNI correspondents from around the world report on a new source of Nigerian aquamarine, black non-nacreous pearl imitations made of beads cut from shell, and the new mineral johnkoivulaite, named after renowned gemologist and photomicrographer John Koivula. @chapter:3


Publication Year: 1986 Title: The Gemological Properties of the Sumitomo Gem-Quality Synthetic Yellow Diamonds Abstract: The distinctive gemological properties of the gem-quality synthetic yellow diamonds grown by Sumitomo Electric Industries are described. These synthetic diamonds, produced on a commercial basis, are grown as deep yellow single crystals in sizes up to 2 ct. The material is currently marketed for industrial applications only, in pieces up to about 0.40 ct. The synthetic diamonds can be distinguished by their ultraviolet fluorescence (inert to long-wave; greenish yellow or yellow to short-wave); their unusual graining, veining, and color zonation under magnification; and the absence of distinct absorption bands in their spectra. @chapter:11


Publication Year: 2014 Title: Exceptional Gem Artistry in Sunstone, Rutilated Quartz, and Beryl – Tucson 2014 Abstract: Figure 1. The morganite carving on the left was inspired by the floating watches in the famous Salvador Dali painting “The Persistence of Memory.” The geometric carvings on the right look simple when the stone is viewed from the base but produce an array of bright reflections and crystalline brilliance when viewed from above. Photo by Eric Welch; courtesy of Sonja Kreis.

	Alexander KreisUnique Jewelry

	In this series of three videos, Idar Oberstein-trained gem cutter Alexander Kreis relates the different approaches he takes to unlock the beauty of a variety of rough gemstones, which include Oregon sunstone, various beryl colors, and rutilated quartz. He tells us the influences that play into his unique designs; it might be the pure, crystalline beauty of a flawless piece of rough or the presence of striking inclusions, which drive him to produce beautiful pieces of wearable art.
At the GJX show, Sonja Kreis (Unique Jewelry, Niederworresbach, Germany) displayed exceptional examples of the jeweler’s and gem carver’s art. Kreis designs the jewelry, and her son Alexander cuts the gems.

	Figure 2. The Oregon sunstones in this fantasy-cut pendant and ring, displaying deep red color and intense stripes of schiller, were cut from the same piece of rough. Photo by Eric Welch; courtesy of Sonja Kreis.

	Figure 3. Left: Alexander Kreis displays one of his unique pieces: a star-shaped rutilated quartz. Right: This superb 442.78 ct faceted Brazilian quartz with rutile inclusions is typical of Kreis’s art. According to Kreis, the orientation of the needles is the most important decision in the design of the finished gem. Photos by Eric Welch (left) and Robert Weldon (right); courtesy of Sonja Kreis.
Alexander Kreis explained that their family has a tradition of over 500 years of gemstone cutting and jewelry manufacture. He apprenticed as a traditional gem cutter, but elected to find his own path to unlock the beauty of fine gem crystals. His cutting is a spectacular blend of freeform curves and dramatic geometrical cuts. Alexander works with many materials, including tourmalines and beryls (figure 1), but Oregon sunstones (figure 2) and rutilated quartz (figure 3) are among his favorites. The fine Oregon sunstone was on display at their booth. Alexander’s father, Stefan Kreis, described their very strict criteria for selecting rough. On a visit to a set of mines in Oregon’s Rabbit Basin, they selected 395 grams of rough out of the 50 kg they were shown; one such piece of rough is featured in figure 2. @chapter:26


Publication Year: 2023 Title: An Iridescent “Insect Wing” in Diamond Abstract: A subsurface feather in diamond resembling an insect wing, with visible iridescence caused by thin-film interference. Photomicrograph by Matthew Hardman; field of view 2.90 mm.
Diamond is very resistant to scratching and is often referred to as the hardest mineral on Earth due to its compact crystal structure. However, diamond is not indestructible, and it can be fractured or even broken apart during ascent from the mantle to the earth’s surface through fast, violent kimberlite eruption. Collision with rocks in high-energy rivers also results in percussion marks on the surface of alluvial diamonds (e.g., J.W. Harris et al., “Morphology of monocrystalline diamond and its inclusions,” Reviews in Mineralogy and Geochemistry, Vol. 88, No. 1, 2022, pp. 119–166). Surface cracks extending into the interior of a diamond are referred to as “feathers” in the gem trade, and these often have a negative effect on the clarity grade.
Fractures within diamond can cause fascinating optical phenomena on rare occasion. The authors recently examined a 0.39 ct Fancy Deep brownish yellowish orange type Ib/IaA diamond containing multiple feathers and graded as I2 clarity. These natural features had not been filled with a clarity-enhancing material. The largest feather located on the table facet of the diamond resembled an iridescent insect wing (see above).
Iridescence is an optical phenomenon caused by interference of light, typically seen in gemstones with cleavage or repeating submicroscopic structures (e.g., X. Lin and P.J. Heaney, “Causes of iridescence in natural quartz,” Spring 2017 G&G, pp. 68–81). In this diamond, the feather’s iridescence was due to thin-film interference caused by a thin film of air with a thickness similar to the wavelength range of visible light. As diamond and air have very different refractive indices, there is a phase difference between the incident light reflected from the upper and lower boundaries of the thin film, resulting in constructive and destructive interference. When viewed using a broadband light source (light consisting of a wide range of wavelengths), constructive or destructive interference intensifies or attenuates certain wavelengths (colors), respectively, producing a rainbow-like interference pattern. @chapter:35


Publication Year: 2000 Title: Fall 2000 G&G Book Reviews Abstract: “The Microworld of Diamonds”
By John I. Koivula, 157 pp., illus., publ. by Gemworld International, Northbrook, IL, 2000. US$95.00

“Gemstones: Quality and Value, Volume 1”
By Yasukazu Suwa, 143 pp., illus., publ. by Sekai Bunka Publishing, Tokyo (2nd ed., English translation), 1999. US$84.00

“The Diamond Formula— Diamond Synthesis: A Gemmological Perspective”
By Amanda S. Barnard, 166 pp., illus., publ. by Butterworth-Heinemann, Oxford, England, 2000. US$39.95

“Gems and Gem Industry in India.”
By R. V. Karanth, 406 pp., illus., publ. by the Geological Society of India, Bangalore, India, 2000. US$75.00 (hardbound), US$60.00 (paperback). E-mail: gsocind@bgl.vsnl.net.in

“Black Opal”
By Greg Pardey, hardcover, 204 pp., illus., publ. by GP Creations, Urungan, Queensland, Australia, 1999. With video (running time 1 hour 52 min.). US$99.95. www.gpcreations.senet.com.au

“Diamonds and Mantle Source Rocks in the Wyoming Craton with a Discussion of Other U.S. Occurrences”
by W. Dan Hausel, Report of Investigations No. 53, 93 pp., illus., publ. by the Wyoming State Geological Survey, Laramie, WY, 1998, US$10.00

To view the full section, download the PDF above. @chapter:29


Publication Year: 2013 Title: Books: Fashion Jewellery: Made In Italy Abstract: By Deanna Farneti Cera, 392 pp., hardcover, illus., publ. by the Antique Collectors Club, Woodbridge, UK, 2013. US$85.00

              This hefty tome’s frontispiece, a nearly foot-long image of an early 1970s Gianfranco Ferré silvery metal brooch hand-fashioned in the shape of Italy, alerts readers that they are in for a wild ride.

Written by Deanna Farneti Cera, a curator for international jewelry exhibits and formerly of the Municipal Museum of Modern Art in Bologna, the book chronicles the rise of Italian fashion jewelry from traditional roots to the most raucous of catwalks.

Italian fashion jewelry from the first half of the 20th century left little in the way of artistic footprinting, as years of war, a Fascist regime, and economic hardship all took a toll. Nonetheless, pieces by Edoardo Saronni from the early part of the century display the ingenuity and craftsmanship that would mark the work of later Italian artisans and artists. After World War II, Giuliano Fratti achieved fame using materials that were allowed during Fascist rule such as raffia, wood, berries, and nuts.

Despite a pervasive Francophilia among fashionistas, Italian fashion jewelry began to take flight in earnest during the 1950s, with the rise of an industrial bourgeoisie and the birth of organized fashion consortia in Milan, Florence, and Rome. Moving beyond roots in theatre, opera, and fine jewelry, Italian designers not only embraced mid-century trends but also forged ahead with bold, inventive designs that stood apart from the staid and two-dimensional.

By the 1970s, “Made in Italy” had become the de rigueur fashion statement, as illustrated by Ugo Correani’s designs for Valentino and the architectural accessories of Gianfranco Ferré, whose celebrated fashion career began with non-precious jewelry. Farneti Cera continues the visually stunning romp through the over-the-top ’80s the colorful supermodel years of the ’90s, and into the millennium’s rock-inspired catwalks and fashion show happenings.

The author offers a few pages of introductory text to each era, followed by a barrage of captivating images of the pieces themselves and as worn by fashion models. Some pieces are shown in advertisements or featured on magazine covers of the time. A few sketches, images from private collections, and photographs from fashion house archives round out the book’s colorful, eye-popping appeal.

The text cites many cultural and historical touchstones that help set the tone for the period, which helps explain the artistic expressions that flowed from these trends. American readers may not be aware of the fear of terrorism that loomed over Italy during the 1970s and 1980s. Some of these passages make for difficult reading in a book focused on beauty and art, yet such events help frame the brazen fashion fringe, typified by Moschino, that emerged once those fears had been exorcised.

Toward the end of the book, Farneti Cera devotes 17 pages to profiles of the jewelry manufacturers whose works graced the preceding pages. These individuals and houses are listed alphabetically, which may strike some readers as being at odds with the book’s chronological focus. The narrative sometimes lacks the flow to deliver such an engaging subject.  Readers may find it easier to navigate some of the book’s occasionally impenetrable and stilted text by referring back to these manufacturers’ profiles as they peruse the images of their works, instead of waiting to reach the back pages.

The book concludes with two “Will They Be Famous?” sections—one with the work of up-and-coming artists, and the other comprising their biographies. The author uses these pages to express her own wish lists for these and future artists, with a reasoned proposal for a craftsman/artist cooperative to help aspiring talents overcome some of the difficulties associated with the business side of their art. Farneti Cera also bemoans the dearth of jewelry galleries or museums in Italy that serve to engage and educate the public about the rich history of ornamentation.

In piecing together this treasure trove of signature Italian style, the book brings readers closer to understanding the appeal and artistry of jewelry making beyond that which is traditionally associated with fine jewelry. Here, fashion jewelry reigns as contextual art. Jewelry designers, illustrators, manufacturers, historians, and curators will enjoy this book, as will readers who long for an Italian holiday or those who are merely intrigued by fashion’s sublime and at times allegorical roots. @chapter:16


Publication Year: 1987 Title: The Rutilated Topaz Misnomer Abstract: Recently a number of faceted Brazilian topazes containing brownish yellow acicular inclusions of what has been described by some gem dealers as the mineral rutile have appeared on the market. An investigation of this material shows that these inclusions are not rutile but rather are open channels colored by limonite. @chapter:3


Publication Year: 2015 Title: Pezzottaite Debuts as the Newest Trapiche Gem Mineral Abstract: Figure 1. As viewed through the pinacoid face, strong oblique fiber-optic lighting illuminates the six-legged trapiche structure emanating from the c-axis of this doubly terminated 2.33 ct pezzottaite crystal. Photo by Kevin Schumacher.

Since the first enigmatic six-spoked emeralds were sent to GIA in the mid-1960s for analysis (H.L. McKague, “Trapiche emeralds from Colombia,” Fall 1964 G&G, pp. 210–213, 223), the family of trapiche-type gem minerals has grown to include a variety of species and morphologies. One of the latest mineral varieties to exhibit the rare trapiche form is a relatively new and rare mineral itself: pezzottaite.

Following its appearance at the 2003 gem shows in Tucson, pezzottaite has quickly become an item coveted by gem and mineral collectors around the world. A member of the beryl group and with trigonal symmetry (the beryl species has hexagonal symmetry), it was approved by the International Mineralogical Association in September 2003 as a unique species and named after mineralogist Dr. Frederico Pezzotta (see B.M. Laurs et al., “Pezzottaite from Ambatovita, Madagascar: A new gem mineral,” Winter 2003 G&G, pp. 284–301).

In 2004, while working in the gem markets of Mae Sai and Mae Sot along the border of Thailand and Myanmar, Elaine Rohrbach of Gem-Fare obtained a small collection of pale pink trapiche crystals and crystal fragments reported to be of Burmese origin. Laboratory analysis later proved these crystals to be the cesium-containing mineral pezzottaite (previously confirmed localities include Madagascar and Afghanistan).

Figure 2. Another well-developed, doubly terminated pezzottaite crystal from the same
locality, weighing 6.17 ct and measuring 11.19 × 10.71 × 8.61 mm, has separate crystals
growing at random angles on each pinacoid face. Each of these smaller crystals also
exhibits trapiche growth. The white trapiche growth reaches all six prism faces in both of
the tabular crystals, as well as those faces on the secondary growth crystals. Photo by
Elise A. Skalwold.
A doubly terminated, well-developed crystal obtained by one of the authors (JIK) exhibits the tabular prismatic habit characteristic of the species, but with a complete six-spoke trapiche structure that is clearly visible in both reflected and transmitted light (figure 1). Another doubly terminated crystal obtained by author EAS from the same parcel shows secondary crystals growing out of each pinacoid face, each of which are also trapiche crystals (figure 2). Similar to trapiche crystals of other mineral species, each of the spokes radiates from the central c-axis toward the prism faces and in a plane parallel to the basal pinacoid. Exploring the former crystal’s inner world revealed not only the details of the white spokes and a spray of golden brown needles and eye-visible black needles, but also a delightful surprise: minute euhedral blue crystals (figures 3 and 4). Unfortunately, the black needles were not identifiable despite their distinct Raman spectrum. Due to their depth within the host, the brown needles and blue crystals remain mysteries as well. Let this be a lesson that nondestructive testing cannot always provide answers, but we can be content with exploring the beauty of the micro-world while leaving some mysteries for the future.

Figure 3. Eye-visible dark needles were seen throughout the pezzottaite crystal with diffused transmitted illumination. Despite a clear Raman signal, the features could not be conclusively identified. Photomicrograph by Nathan Renfro; field of view 1.10 mm.

Figure 4. Using diffused transmitted and oblique fiber-optic illumination, a golden-brown spray of needles is shown deep in the crystal, along with a bright blue crystal to its right. Their depth precluded analysis by Raman spectroscopy. Photomicrograph by Nathan Renfro; field of view 0.91 mm. @chapter:5


Publication Year: - Title: Diamond Care and Cleaning Guide Abstract: Consumers know diamond from the slogan “A Diamond is Forever”. With some care considerations this is relatively true. The Asscher cut was popular decades ago and is again a very popular cut style. This stone has exceptional quality being D color and VVS2 Clarity.

                      “A Diamond is Forever” is one of the world’s best-known advertising slogans. It has many different meanings. It refers to diamond’s timeless appeal. It refers to diamond’s icy beauty. And it also refers to diamond’s durability. One result of the diamond formation process is its incredible durability.

Durability is a gemstone’s ability to withstand wear, heat, and chemicals. Durability consists of three properties: hardness, toughness, and stability. Hardness means how well a gemstone resists scratches and abrasion. Toughness describes how well a gemstone resists breaking and chipping. Stability means how well a diamond resists chemicals and temperature changes.

Hardness
Gem and mineral hardness is measured on the Mohs scale. The scale originated in 1812 when German mineralogist Friedrich Mohs chose ten minerals and assigned numbers to them, based on the relative ease or difficulty with which one could be scratched by another. But the Mohs scale is deceptive. The steps between the minerals are not evenly spaced. For example, diamond is only one number away, but it’s many times harder than gems in the corundum family. Only a diamond can scratch a diamond.

Something the Mohs scale doesn’t show, but that’s equally important to the diamond industry, is that diamond can also scratch any of the precious metals used for settings. That means a diamond that’s loose in its setting can wear through a prong over time.

	Diamond rates highest on the Mohs hardness scale, at number 10.
Toughness
Any stone, including a diamond, will break if it’s hit hard enough in the right place. Toughness is a measure of how well a gem can survive an impact and resist breaking, chipping, or cracking.
Diamonds are tougher in the directions where the atoms are bonded tightly together, less tough where they’re not so tightly bonded.

	Cutting styles with pointed corners or ends are often set with prongs to protect the corners from chipping. - Courtesy Ambar Diamonds
The weakest directions are the ones where the atoms are farthest apart. It’s easier to break a diamond in those directions, which are called cleavage directions. A cutter can cleave a diamond by hitting it sharply in the cleavage direction. But even after cutting, a hard blow can still cleave a diamond. This can happen during the setting process, or even when it’s being worn.

Stability
Stability is a term that describes how well a diamond resists temperature changes and chemicals. Diamonds are very stable. They’re invulnerable to virtually all acids, for one thing. The cutting process generates a lot of heat, but diamonds usually endure intact. Situations that are more threatening to a diamond’s stability are those that involve sudden and extreme temperature changes. Those changes can cause thermal shock and create new fractures and cleavages or cause existing ones to spread.

Diamonds will burn at about 1562°F (850°C). House fires and jewelers’ torches can reach that temperature.

	A house fire caused the white, cloudy appearance of this diamond (left). The stone was recut to remove the burned area, reducing the diamond’s size, but leaving no sign that it was ever damaged (right).
Cleaning
Diamonds can be cleaned safely with lint-free cloths, commercial jewelry cleaning solutions, and household detergents.

Harsher cleaning methods are not recommended for home use. These include powdered abrasive household cleansers, ultrasonic cleaners, and steam cleaners.

	Ultrasonic cleaners and steam cleaners can loosen gemstones in their settings. Jewelry professionals carefully examine jewelry for loose stones before using these devices. @chapter:31


Publication Year: 2021 Title: Melo Pearl Found in a Melo Shell Abstract: Figure 1. A Melo pearl measuring 20.50 × 19.25 × 18.85 mm and weighing 55.10 ct. A fine crack is visible across the center of the surface. Photo by Nutapol Kitdee.

Over the years, there have been a number of reports relating discoveries of natural pearls in edible oysters (e.g., Fall 2019 Gem News International, pp. 439–440; Fall 2020 Lab Notes, pp. 420–422). However, similar discoveries are much rarer in gastropods, such as species of the Melo genus. Such finds often make headlines, as was the case recently in Thailand when a few discoveries were reported on social media. One of these remarkable stories, titled “A delicious find,” was posted on www.facebook.com/GIAEducation on April 9, 2021. It detailed the discovery of a large oval orange Melo pearl measuring 20.50 × 19.25 × 18.85 mm and weighing 55.10 ct that was submitted to GIA’s Bangkok laboratory for testing in September 2020 (figure 1). The owner claimed to have accidentally found this pearl in an inexpensive Melo shell he purchased with another shell from a local market in Rayong Province, eastern Thailand.

Figure 2. Various flame structure patterns visible on the pearl’s surface: short patchy flames with a fine surface-reaching crack (left), thin elongated flames with some minor natural features (center), and flames reminiscent of Christmas trees (right). Photomicrographs by Kwanreun Lawanwong; fields of view 19.20, 7.20, and 3.60 mm, respectively.
This note offers additional detail on the pearl that was the subject of that story. To the eye, the pearl looked exactly as a Melo pearl should. Its size and color were consistent with that type of pearl, and it exhibited various flame structure patterns on its surface: short patchy flames, thin elongated flames, and “triangular” flames reminiscent of Christmas trees (figure 2). These features were consistent with flame structures previously observed on Melo pearls (D.J. Content, Ed., Pearl and the Dragon: A Study of Vietnamese Pearls and a History of the Oriental Pearl Trade, Houlton, Maine, 1999, pp. 90–92; H. Htun et al., “Melo ‘pearls’ from Myanmar,” Fall 2006 G&G, pp. 135–136; V. Pardieu, “Concise Field Report: Melos and their pearls in Vietnam,” GIA Research News, https://www.gia.edu/ongoing-research/melo-pearls-from-vietnam, 2009). Some other associated minor surface features were visible, together with a long fine crack traversing one area (figure 2, left).

Figure 3. Microradiographs in two directions showed no obvious internal growth structure. Only a fine dark line showed in one orientation, which corresponded to a surface-reaching crack (left, indicated by the white arrows).
Microradiography revealed no obvious internal growth structure (figure 3). Only the fine crack previously mentioned showed as a dark fine line in the correct orientation (figure 3, left, indicated by the white arrows). The absence of any surface modification and the presence of natural surface features, in addition to the lack of banded structure typically observed in shell samples, proved this was a pearl and not an imitation fashioned from Melo shell (Summer 2006 Lab Notes, pp 166–167; N. Sturman et al., “An imitation Melo pearl,” GIA Research News, https://www.gia.edu/gia-news-research/imitation-melo-pearl, 2011).
Spectral analyses using Raman, photoluminescence (PL), and UV-Visible (UV-Vis) spectroscopy proved the pearl’s color was of natural origin. Raman spectra revealed features at 701, 705, and 1085 cm–1 identifying aragonite, together with polyenic peaks at 1130 and 1520 cm–1 responsible for the orange coloration. These polyenic peaks are consistent with other naturally colored porcelaneous pearls (S. Karampelas et al., “Polyacetylenic pigments found in pearls and corals,” 30th International Gemmological Conference Proceedings, 2007, pp. 49–51; Summer 2018 Lab Notes, pp. 211–212).
An interesting declaration made by the pearl’s owner probably explains the presence of the fine eye-visible surface crack. The Melo shell containing the hidden pearl was boiled, and the Melo pearl was only discovered when the meat was being prepared for consumption. Hence, it is likely that the temperatures and duration applied during the cooking process caused the crack’s formation. This point has been mentioned by a number of pearl traders during discussions with lab gemologists over the years, so it seems an important consideration when such cracks are observed. Even so, the notable size, unmodified surface, perfectly formed oval shape, and intense natural color all combined to make this a desirable and special pearl. @chapter:14


Publication Year: 2016 Title: Iridescent Inclusion in Tanzanite Abstract: Figure 1. The iridescence in this tanzanite hints at the complex and dynamic world just below the surface, in the form of crystallographically aligned iridescent cleavage. Photomicrograph by Danny Sanchez; field of view 3 mm.

	Gemmy blue zoisite, more commonly known as tanzanite, is valued for its pleasing violet to blue hue. One tanzanite specimen from Merelani, Tanzania, was purchased by the author for an entirely different aesthetic feature: its well-defined, minimally damaged crystal faces. Microscopic observation uncovered a hidden bounty of color just below the surface, particularly when subjected to metal halide oblique lighting. Crystallographically aligned, vividly iridescent colors resulting from fine separations along the stone’s cleavage planes (figure 1) were visible using fiber-optic light.

	Photographing inclusions can be challenging, to say the least. When light enters the host material, each delicately nuanced feature is affected in unpredictable ways. Documenting surface textures or crystal faces is equally difficult; the challenges are manifold when attempting to photograph both simultaneously. Knowledge of lighting techniques is useful in such situations (N. Renfro, “Digital photomicrography for gemologists,” Summer 2015 G&G, pp. 144–150). In this instance, a combination of diffused lighting and direct pinpoint lighting was used to illuminate both features. Low-intensity diffused light was reflected from the surface of the stone so as to illuminate the crystal faces without overpowering the iridescent colors brought from below. Once lit, a short “stack” of images captured the appropriate amount of depth into the stone. @chapter:6


Publication Year: 1989 Title: Spring 1989 Gem News International Abstract: Tucson ‘89
            "Angelite"
            Garnet
            Man-Made "Inclusion" Specimens
            Mother-of-Pearl Gambling Chips
            Plastic Cameo Imitations
            Synthetic Quartz
            Tourmaline from Nigeria
Colored Stones
            A Beautiful New Form of Orthoclase
            New Emerald Deposit near Nova Era, Brazil
            Record-Size Spessartine Garnet
            Star Almandine Garnet from Idaho
            Wollastonite for Carving
Instrumentation
            New Developments in Spectroscopy
Synthetics and Simulants
            Recent Advances in Gem Diamond Synthesis
            Synthetic Diamonds by Detonation
            Synthetic Diamond vs. Cubic Zirconia
            Emerald Imitation from Quartz
            Heat-Treated Lepidolite?
            Imitations from Africa
            "Reconstructed" Azurite-Malachite
            Synthetic Amethyst Alert
Erratum
            Mr. Francisco Muller Bastos: 1988 G&G Challenge
In Memoriam
            Irwin Moed 1918-1988 @chapter:23


Publication Year: 2006 Title: Winter 2006 G&G Lab Notes Abstract: Lizards in Imitation Amber
Large Demantoid Garnet of Exceptional Color
Unusually Large Fancy White Diamond with Whitish Banding
Prolonged Change of Color in Pink Diamond
Strand of Natural Nacreous and Non-nacreous Pearls
Poudretteite
Pyroxmangite, an Unusual Gem

To view the full section, download the PDF above. @chapter:8


Publication Year: - Title: Liddicoatite: Vibrant Gem Honors Father of Modern Gemology Abstract: Most liddicoatite comes from Madagascar, including this slice from the Anjanabonoina pegmatite. Coutresy Harvard Mineralogical Museum, photo by Robert Weldon/GIA

                      Liddicoatite – a calcium-rich lithium tourmaline – is revered for its complex color zoning that often displays several vibrant colors. The common trigonal pattern comes to life when the gem is fashioned as polished slices that highlight the characteristic red, purple, green and yellow hues of this striking gem. Multicolored zoning – what gemologists refer to as parti-colored – occurs when the trace elements change in concentration or composition during a crystal’s growth.

First recognized as a separate mineral in 1977, liddicoatite was named in honor of Richard T. Liddicoat (March 2, 1917 – July 23, 2002), the second president of GIA who is often referred to as the “Father of Modern Gemology.” Dr. Pete J. Dunn and his colleagues from the U.S. National Museum of Natural History identified liddicoatite as a distinct mineral and chose the name in recognition of Liddicoat’s many contributions to gemological knowledge and education, including his creation of the International Diamond Grading System and its well-known and universally recognized scales for measuring the color and clarity of diamonds.

Liddicoatite – along with elbaite, dravite, uvite and schorl – is one of the major tourmaline species. Its appearance is similar to elbaite, and it can only be distinguished through chemical analysis. Most known liddicoatite comes from the Anjanabonoina pegmatites in central Madagascar.

View Gallery @chapter:5


Publication Year: 2024 Title: New Sapphire Material from Kashmir Abstract: Figure 1. Left: Two Kashmir sapphire rough crystals: 77.00 ct unheated (left) and 25.20 ct heated (right). Right: Unheated Kashmir sapphires. Left to right: 1.29 ct pear shape, 2.60 ct cushion cut, 21.09 ct dragon carving, and 4.08 ct oval cut. Photos by Robert Weldon; courtesy of Eddie Cleveland of KashmirBlue and Jeffery Bergman of EighthDimensionGems.
The legendary and remote sapphire mines of Kashmir, the disputed Himalayan territory between India and Pakistan, produced the finest-quality sapphires from 1890 through the 1920s. These coveted gems made their way south to Mumbai and eventually to Europe and America. Now, 100 years later, rough stones are still found, deposited through erosive processes. During the summer months, Kashmiri shepherds migrate north through the higher Himalayas, where they occasionally find sapphires in the riverbeds and on the hillsides. The glacier-tumbled rough typically exhibits rounded surfaces, affectionately referred to as “plums in pudding” by English geologist C.S. Middle in the 1930s (figure 1, left). Many in the trade believe the best available material dates back to five productive years in the 1880s.

Figure 2. Two untreated Kashmir sapphire rings. Top: 1.59 ct cushion-cut cornflower blue sapphire set in white gold with VVS baguette diamonds. Bottom: 1.00 ct oval-cut medium lighter blue sapphire set in an Art Deco style diamond platinum ring. Photo by Robert Weldon; courtesy of Eddie Cleveland of KashmirBlue and Jeffery Bergman of EighthDimensionGems.
Exhibited at the AGTA show by Jeffery Bergman (EighthDimensionGems, Bangkok) and Mayer & Watt (Maysville, Kentucky), this selection of newly found rough crystals, loose cut gems (figure 1, right), and mounted Kashmir sapphires (figure 2) was all recently faceted by lapidary artisan Eddie Cleveland of KashmirBlue, who lived in Kashmir researching the historic mines for more than a decade. Cleveland uses his heat-treating experience to turn much of the pale grayish geuda-like rough to rich, well-saturated blues through standard high-temperature heating techniques. A limited amount of new material is found each year, and only a few pieces find their way to market. @chapter:1


Publication Year: 1983 Title: Fall 1983 G&G Lab Notes Abstract: A Large Cat's-Eye Alexandrite
Amber, in Plastic
Diamond Simulant
Mysterious Wear on a Diamond Ring
Painted Diamonds
Diaspore, a Rare Gem Material
Emerald
Jade Substitute
Lapis Lazuli, a New Imitation
Synthetic Opal
Cultured Button Pearls
Pinite, a Massive Form of Muscovite
Zoisite (Tanzanite)

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


Publication Year: 1995 Title: Fall 1995 G&G Book Reviews Abstract: “Standard Catalog of Gem Values, 2nd Edition”
By Anna M. Miller and John Sinlzankas, 271 pp., illus., publ. by Geoscience Press, Tucson, AZ, 1994. US$24.00

“Diamond Exploration into the 21st Century”
Edited by W.L. Griffin, 367pp., illus., publ. as Vol. 53 of the Journal of Geochemical Exploration, Elsevier Science, Amsterdam, 1995, US$250.

 “The New Alchemists: Breaking Through the Barriers of High Pressure”
By Robert Hazen, xvi, 287pp., illus., publ. by Smithsonian Press, Washington, DC, 1993. US$23.00

To view the full section, download the PDF above. @chapter:29