Publish Year: 2019 Title: Unusual Faceted Gemstones Abstract: Figure 1. A pink 173.22 ct fluorite, measuring 35 × 33 mm, from Uri, Switzerland. This stone is representative of minerals discovered by strahlers, mineral hunters from the Swiss Alps. Photo by Kevin Schumacher, courtesy of Gravier & Gemmes.

Denis Gravier of Gravier & Gemmes (Poncin, France) exclusively sells rare and unusual faceted stones, such as the pink fluorite from Switzerland shown in figure 1. During the GJX show, he shared insights about the market for such gems.
Gravier developed a passion for colored stones and minerals while growing up in the French countryside. He studied mineralogy, crystallography, and petrology before traveling to the Republic of the Congo, Pakistan, Mexico, the former Yugoslavia, and Morocco a few decades ago to collect mineral specimens. He also learned gemstone cutting techniques. With the knowledge and experience he gained, he decided to open a company specializing in faceted stones of unusual varieties. Some of these gems, he explained, are rarely if ever used in jewelry. The challenge is finding them, but after decades of traveling and visiting the mines, he knows many people in the trade. Now the stones come to him during major shows, so it is no longer necessary to go to the sources. He still travels occasionally to Sri Lanka and Madagascar, where he buys rough that he will have cut in France or overseas. Gravier says Tucson “is a great show…you can almost see all that is available in the world at that time during the show.” In Tucson he meets with clients from the U.S., Japan and other parts of Asia, and European countries.
In terms of novelty and rarity, Madagascar offers the largest variety and supply. New gemstones are always emerging, Gravier explained. Among his stones from Madagascar were the dumortierite and green sphene in figure 2.

Figure 2. Unusual stones from Madagascar. Left: A 0.51 ct dumortierite (5.4 × 4.5 mm). This mineral, commonly known as an inclusion, is now available in very limited quantities as a gem. Right: A 19.65 ct round-cut green sphene. Photos by Kevin Schumacher, courtesy of Gravier & Gemmes.

Figure 3. A 1.21 ct intense yellow legrandite, a rare zinc arsenate mineral from Mexico. Since the last discovery of this mineral in the 1970s, it has appeared on the market only sporadically. Photo by Kevin Schumacher, courtesy of Gravier & Gemmes.
He also described the market for unusual faceted gems. Collectors, not the jewelry industry, are the clientele for rare stones in France and around Europe, which is dominated by the “Big Three” and diamond. Faceted legrandite (figure 3), grandidierite, and dumortierite, for example, are generally not used in jewelry pieces. On the other hand, in Asia, especially Japan, people are attracted by rarity and there is a demand for “exotic” quality material, even in small sizes, for use in jewelry. Gravier feels that more people there have a general knowledge of and interest in gemology and colored stones. The Chinese market is becoming increasingly important for his business. One benefit of the rare stone market is that treatments are not common among these gems, making it a good source for people seeking untreated material.
Even though there is growing competition, with goods at all price points available on the Internet and aggressive marketing through the web and social media activity, Gravier chooses not to sell on the Internet. He invests in improving the quality and variety of his stock, relying on his long-term relationships with clients and suppliers.
Gravier sees a rising interest in rare stones. He believes he is helping to create more appreciation for a wide range of colored stone varieties. He hunts for rare treasures and, as an ambassador for unusual stones, gives them a chance for public exposure and recognition.

	Unusual Faceted Gemstones @topic:2


Publish Year: 2006 Title: “Paraíba”-Type Copper-Bearing Tourmaline from Brazil, Nigeria, and Mozambique: Chemical Fingerprinting By LA-ICP-MS Abstract: Gem-quality bright blue to green “Paraíba”-type Cu-bearing tourmaline is now known from deposits in Africa (Nigeria and Mozambique), in addition to three commercial localities in Brazil (in Paraíba and Rio Grande do Norte States). Stones from these new localities have been mixed into parcels from the original Brazilian Paraíba occurrence. The Nigerian and Mozambique tourmalines that show saturated blue-to-green colors cannot be distinguished from the Brazilian material by standard gemological testing or on the basis of semi-quantitative chemical data (obtained by EDXRF analysis). However, quantitative chemical data obtained by LA-ICP-MS show that tourmalines from the three countries can be differentiated by plotting (Ga+Pb) versus (Cu+Mn), (Cu+Mn) versus the Pb/Be ratio, and Mg-Zn-Pb. In general, the Nigerian tourmalines contained greater amounts of Ga, Ge, and Pb, whereas the Brazilian stones had more Mg, Zn, and Sb. The new Cu-bearing tourmalines from Mozambique showed enriched contents of Be, Sc, Ga, Pb, and Bi, but lacked Mg. @topic:9


Publish Year: 2014 Title: Fine Corundum, Paraíba Tourmaline, and Alexandrite – Tucson 2014 Abstract: Figure 1. This remarkable 112.82 ct Sri Lankan alexandrite, seen under incandescent (left) and fluorescent lighting (right), is unusually large. Photos by Robert Weldon; courtesy of B&B Fine Gems.

              At the AGTA show, Dave Bindra (B&B Fine Gems, Los Angeles) showed us an exceptionally large fashioned alexandrite reportedly from Sri Lanka (figure 1). According to Bindra, it is very difficult to find fine specimens over 5 ct, although Sri Lanka and Madagascar are known to produce sizeable alexandrite crystals. At over 100 ct, this is certainly one of the largest our team has seen. Bindra speculates that the original crystal may have been over 300 ct.

	Figure 2. This heated 33.16 ct emerald-cut royal blue sapphire is from Sri Lanka. Photo by Robert Weldon; courtesy of B&B Fine Gems.
Also on display was a royal blue emerald-cut Sri Lanka sapphire weighing over 33 ct (figure 2). Bindra noted that supply of fine sapphire, while scarce, is currently stronger than fine ruby. Compared with rubies of equivalent price, fine sapphires offer more size and quality; as a result, prices have risen dramatically over the last two years. This is a function of constricted supply and increasing demand as the Chinese market opens up to premium goods. Only three to five years ago, the strongest demand from Chinese buyers was for mid-range to commercial material. The Chinese are currently consuming the finer items once sought only in Western Europe, the United States, and Japan. As a result, U.S. dealers and consumers have to contend with competition in this market. As Bindra pointed out, this creates “a very interesting dynamic.”

	Figure 3. Fine rubies were scarce and expensive at the 2014 Tucson gem show. According to the dealer, this 9.10 ct Mozambique ruby had only undergone low-temperature heating. Photo by Robert Weldon; courtesy of B&B Fine Gems.
Also at the B&B booth was a superb 9 ct Mozambique ruby (figure 3), one of the finest rubies Bindra has seen from this source. He explained that Mozambique’s rubies are so popular because they come in large, strongly colored crystals; once cut, they produce clean, attractive gemstones. They are very marketable because consumers readily appreciate their beauty. Bindra told us that Mozambique ruby crystals can be a little flat, which constrains the depth of fashioned stones. It is difficult to find a piece of rough above 4–5 ct with fine color suitable for cutting a clean gemstone; this makes the 9 ct ruby exceptional. A gem of this quality might sell for US$50,000 per carat or more.

By comparison, Burmese rubies are increasingly difficult for domestic dealers to obtain due to the U.S. embargo against Myanmar. Trade is limited to gems that predate the ban and were already in circulation in the United States.

	Figure 4. Dave Bindra shows off a superb 14.59 ct oval faceted Brazilian Paraíba tourmaline. Gems of this quality above 1 ct are extremely rare, making this gem exceptional. Photos by Eric Welch (left) and Robert Weldon (right); courtesy of B&B Fine Gems.
Finally, Bindra showed us what he described as the star of his show: a 14.59 ct Brazilian Paraíba tourmaline, reportedly unheated (figure 4). He was fortunate enough to acquire this stone out of a collection. The previous owner had purchased it years ago when the material first came out, making this another example of recirculation rather than current production. Bindra confirmed the importance of the secondary gem market, which has become critical to dealers because there is so little material coming from deposits. With so much competition at the source—especially when a deposit, such as Paraíba, is reportedly depleted—dealers have no choice but to look in the secondary market. @topic:2


Publish 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. @topic:2


Publish Year: - Title: A Sunstone Odyssey, Part 1: The Ponderosa Abstract: John Woodmark, CEO of the Ponderosa mine, is a man in his element. Photo by Robert Weldon.

THE MINE'S LOCATION

View Gallery

	In this slideshow, you will explore the Ponderosa mine, learn about its gem recovery processes, and view the beautiful sunstones that originate in the rocks of southeastern Oregon.
With a sweep of his arm, John Woodmark invites us to take in the majestic vista below: “You can see the large meadow… it stretches for miles. That used to be an ancient lake…Native American people have been in here for 15,000 years, hunting around that lake.” He adds some more-recent history, telling us: “Into the 1900s, they were still camping in this area and using the dried-up lake bed as pasture for their horses.”

This connection to the native people extends to the present day. Woodmark partners with the local tribal outreach program to offer seasonal employment to Native American teens at the Ponderosa mine. This is something Woodmark is very proud of, and we’ll return to it a little later.

Right now, we’re standing on the steep slopes of Donnelly Butte, just above the Ponderosa mine’s pit. At our backs, magnificent stands of lofty ponderosa pines extend uphill. We are about a five-hour drive from Portland, Oregon, and the transition from that busy city to the silence and serenity of the Ponderosa is jarring.

Beneath us, entombed in an ancient lava flow, millions of carats of rough sunstone—Oregon’s state gemstone—await discovery. The Ponderosa mine is possibly the state’s most important source of the repeatable commercial sizes required by jewelry manufacturers.

	The red rocks of the Ponderosa mine’s pit complement the setting sun. Photo by Robert Weldon.
The beauty of the mine’s location isn’t lost on Woodmark: “It’s a pristine area, it’s beautiful…It’s wonderful just to come up here, let alone find a truly exotic gem like Oregon sunstone.” With this in mind, he strives to make his mining activities as low-impact as possible: “We’ve got over a million board feet of huge ponderosa, most of them in the 250 to 300 year old range, and we’re trying very hard not to disturb any of those trees and still get the same stones that we need to mine.”

Beyond the direct environmental impact, Woodmark and his crew also have to synchronize their mining to the regional climate. These are Oregon’s High Lava Plains, after all, and the winters can be brutal: “The mine is located at 5900 ft., so from October to June we’re covered with as much as ten feet of snow up here, so there’s absolutely no mining during those months.”

Despite these constraints, he knows the Ponderosa’s weathered reddish basalts are blessed with high concentrations of sunstone: “This mine is tremendously rich—the whole mine is 60 acres—and we get a kilo and a half of sunstone out of every cubic yard of dirt moved…so it’s arguably one of the richest gemstone mines in the world.”

Because of the richness of this deposit and the weathered nature of the basalt around the gems, they’re easier to recover than at some of Oregon’s other sunstone locations. Woodmark explains: “We do ten-day mining stints…sometimes four to five times throughout that four month period…It all depends on the demand for Oregon sunstones…the more demand, the more often we mine.”

	Introducing the Ponderosa

	John Woodmark, CEO of Desert Sun Mining & Gem, provides a brief history of the mine and its location, as well as explains how the Ponderosa’s location at 5,900 ft. affects the mining season.

BEAUTIFUL SUNSTONE
Woodmark is passionate about sunstone: “You never get tired of it…it isn’t like you’re mining amethyst, which is all purple. Ours is so many different colors, every stone is unique.” As he talks on, his enthusiasm and love of this unique gem is infectious: “You can get reds, with just a sprinkling of the copper platelets, which makes it look like you’re looking into a red sky with gold stars…It’s just gorgeous.”

	A rare 11.76-ct. bicolor sunstone gleams with an added bonus of glittering, reflective copper platelets. Photo by Robert Weldon.

	This group of red sunstones reflects recent production from the mine’s pit. Photo by Robert Weldon.
He draws our attention to sunstone’s unique hallmark—tiny particles of native copper metal that produce a glittering effect called schiller. “And then you have the intense schiller…When the sun hits it and it just pops out at you…you can’t even believe it!”

	Beautiful Gems, Pristine Location

	Owner John Woodmark introduces us to the Ponderosa Mine’s pristine location and explains how the gems from the mine mirror the natural beauty of the environment.

THE PONDEROSA MINING PROCESS
Woodmark is determined that we see all of the mine’s operations and witness the recovery of gem sunstone directly from the pit wall. We start right at the wall, which bears sets of deep, parallel gouges. He mentions this is the work of the “magic finger,” developed by a member of his crew as an attachment for their backhoe, and which makes mining much easier.

	Pickers scour their screens for the gleam of red sunstone. Photo by Robert Weldon.
He directs us to a rich red area of the pit wall. “In the rest of the mine, we only get about one-and-a-half to three percent red.” This patch, he asserts, is very different: “This area produces twenty percent red to the volume that we’re picking…so rich it’s incredible.”

Woodmark adds that the backhoe’s special attachment—basically a flattened metal spike—was the missing ingredient: “We haven’t monkeyed around with anything else since we got our ‘magic finger’ to break this stuff down. Before, it was too hard for our machines to work.”

Once enough of the pit wall is torn down by the backhoe, a small loader moves the ore onto an area of the pit floor. Next, the Ponderosa crew runs their massive forty-thousand pound loader over the material to crush it and loosen the stones.

The loader feeds the crushed rock through a dry trommel—a rotating screen that, with the harsh clatter of stone on metal, separates the dirt from the ore-bearing material. The next stage is a second trommel, this time using water. John tells us this piece of equipment takes the concentrate and “washes it, scrubs it, and knocks off a little bit of the volcanic crust that’s on the crystals.”

One load fills about twenty five-gallon buckets. The buckets quickly stack up behind each of the three screening stations set up at the time of our visit.

A picker stands behind each screen. Woodmark picks up a bucket of concentrate and pours the contents onto a screen to demonstrate for us: “We…throw all the big rocks off…spread it out fairly evenly…” He picks up a hose and directs a jet of water over the concentrate. “…then come back and spray it down.”

He pauses to pick up a choice piece of sunstone. “Nice red,” he observes. “And then we start…systematically going through the whole screen.” With a small trowel, he works methodically from one end of the screen to the other, telling us, “What we try and do is turn every stone…leave no stone unturned we tell the kids…so you start at one end and you just systematically turn every stone.”

	We recovered this nice specimen of zoned sunstone crystal in host basalt after it passed through the wet trommel. You can see that the crystal was originally considerably larger. Photo by Duncan Pay.
John’s diligence pays off with a small handful of rough sunstone, “You’ll get a handful like that off every screen…which probably weighs a few ounces.” He drops the red pieces into a plastic cup and tosses yellow or colorless rough into a bucket next to his feet. “They’ve got to go through a lot of screens to get a kilo…but like I say, they’ll pick about ten kilos on average per day.”

John emphasizes that speed is of the essence: It’s important to go through the screens quickly but accurately. “Don’t miss a thing, and get on to the next screen.” His rule of thumb is that the more screens you go through, the more you’re going to make: “I’ll do a screen every five-to-six minutes…it’s important not to jump around…because you’ll start to miss them.”

John’s eyes scan methodically from one end of the screen to the other, his trowel making quick movements to flip over the larger pieces: “A lot of our stones have a volcanic crust on them and even though they’ve gone through all the processes to get here, they’re very hard to find, so we go through it very methodically.”

“Don’t leave a stone unturned…” he admonishes us, “…because sure enough, there will be a red one hiding underneath there…and we don’t want to miss a red one.”

Once all the concentrate from a load is recovered, it’s washed for about an hour in a small cement mixer, which takes about 35 kilos at a time (60-70 pounds). “It’s almost like a rock tumbler…a giant rock tumbler,” Woodmark jokes.

When John tips out the mixer, there’s a crystalline glitter and tinkle as freshly washed rough cascades onto a small screen. “I’m looking for how many reds and how much schiller is in there…I’m looking for good stones that will bring money.”

He plucks out a limpid chunk of feldspar. “There’s a beautiful yellow…it’s a nice big size…see how clear and nice that stone is…that’ll make a terrific stone.” And then, a better prize: “Here’s a beautiful red…that’s going to make a tremendous faceted stone!”

The final step at the mine is to grade all this freshly cleaned concentrate. John leads us to a small table in front of the mine’s bunkhouse, where trays of sorted rough—reds, bicolors, schiller stones, yellows, and clears—rest in water-filled metal trays. The water cuts down reflections and helps with grading, he explains. There, in the shadow of tall ponderosa pines, John outlines the qualities a really fine gem might have: “The pinnacle is if it would be good enough to make a carving. A carving has to be something over 25 carats finished.”

He continues, “It has to have all the attributes…color…schiller…so it really is the pinnacle of an Oregon sunstone…We sell them for a lot of money…That’s just one in thousands of stones that we find.”

	Mining Sunstone at Ponderosa

	In this series, Ponderosa Mine owner John Woodmark explains how his crew goes about mining and processing, and grading rough sunstone.

NATIVE AMERICAN PICKERS
John is proud of his partnership with the local tribal outreach program, which started with five kids in 2006 and continues to the present. “We’ll pick for ten days at a stint,” John tells us. “After ten days, they’re burnt out picking stones and standing down there in the hot sun.”

	The Ponderosa partners with the local tribal outreach program to use Native American pickers. Photo by Jeff Jessing, Nature Revealed Photography, © 2009; courtesy of Desert Sun Mining Group
Unfortunately, at the time of our visit, there had been a robbery at the reservation and all the teens had left to assess the damage. However, each of us spent several hours working the screens, just as the pickers do. This gave us a very good concept of these kids’ “Ponderosa experience.”

	A lucky picker’s haul: A fine collection of “reds” decorate this screen. Photo by Robert Weldon
John outlines how his outfit houses, feeds, and pays the teen pickers: “For most of them it’s the most money they’ve ever had of their own…so the kids have all been absolutely great…they’re respectful, they’re glad to have a job, and all of us mentor them around the campfire.”

	A red crystalline glint in a scattering of red rock attracts this worker’s attention.
	Photo by Robert Weldon
To John, the amount of work he can provide hinges on the success of his business and, in turn, the popularity of sunstone with the jewelry-buying public. “The more sunstones we sell, the more people we can then hire,” he explains. “So if more people would get in behind Oregon sunstones, we’d have a lot more kids working here.”

	Employing Native American Teens

	The Ponderosa mine has an arrangement with the local tribal non-profit to provide work experience for Native American youth. The mine’s owner describes the benefits for both parties.

PROFIT
Woodmark is a savvy businessman, successful in many ventures before he acquired the Ponderosa mine. He applies the same financial acumen to sunstone as he would to any other commodity; “A kilo of red is worth twenty thousand dollars…we’ve got 25 of them in five days.”

	This choice piece of red sunstone rough will make a fabulous faceted gem. It’s just one piece in the 25 kilo haul the Ponderosa miners recovered during this trip. By Robert Weldon.
"We average 600 cut carats per kilo…an average price of 100 dollars per carat, I mean…is sixty thousand dollars…times 25…” He leaves us to do the math. “Yeah,” says Woodmark finally with a smile, “I think it’s pretty profitable!”

	Value of Rough Stones

	CEO John Woodmark explains the economics behind sunstone recovery at the Ponderosa mine.

THE GREAT ANDESINE CONTROVERSY
When we ask John about the andesine issue, there’s a hint of resignation in his answer. “Around 2004 or so, we started running into resistance because of a product out of China called andesine.” He explains that the jewelry channels jumped on it because every stone looked exactly alike, and as he puts it, “They could get them for nothing and sell them for a lot.”

Then for four years, while gemologists and geologists the world over tried to prove the authenticity or treated nature of this new gem, sales of Oregon sunstone were flat because people were afraid to invest. John is pragmatic on this topic: “We got hundreds of thousands of dollars’ worth of gemologists’ time and effort to prove that the andesine was a treated stone, but it also verified that Oregon sunstone was all natural.”

John contends that all the publicity over andesine was, in reality, a public relations blessing. “Nobody ever heard about Oregon sunstone before this andesine mess. Now everybody knows andesine was trying to be like an Oregon sunstone.”

In the three years since andesine’s treated nature was confirmed, John asserts his sales have increased year on year.

	Treated Andesine's Impact

	Recent issues with treated feldspar have impacted the market for natural Oregon sunstone. In this video, John Woodmark describes how his business was harmed, but also outlines some unexpected benefits from the affair.

SELLING SUNSTONE
Most consumers know about diamond, ruby, sapphire, and emerald, and might well favor those Big 4 gems. John understands it takes time and effort to open peoples’ eyes to sunstone’s unique attributes. “You have to sell an Oregon sunstone,” he says. “Most customers don’t know what it is.”

“The whole process of educating people and telling them about it,” he explains, “makes the stone personal.”

One of the qualities that make handling sunstone a challenge for commercial jewelry manufacturers—the uniqueness of individual gems might make them hard to match in jewelry—can play well with enlightened consumers looking for something different.

“We tell them about the uniqueness of having the copper particles in the stone, which makes their stone as unique as a snowflake,” John continues. Finally, he adds another set of strengths: “This is an American gemstone, picked by Native Americans…It’s only found in America, and it’s rare and exotic…so you know, it’s a terrific stone.”

	Educating Customers

	CEO John Woodmark explains his belief that the key to acceptance of sunstone as a mainstream gem lies in consumer education. @topic:2


Publish Year: - Title: Tucson Visit Spurs Geology Professor, Publisher to Head Back to School Abstract: Dr. Hobart King, GG, began prospecting for invertebrate fossils in his parents’ limestone driveway as a 6-year-old and tumbling rocks a few years later. He enjoyed a long, established career as a geology professor before purchasing the website Geology.com. “Always be learning,” he says. “Keep your eyes open for new skills, tools, and information that can advance your business.” Courtesy of Geology.com. Photo by Bradley Cole

Dr. Hobart King was already an accomplished geologist with more than 40 years of experience, 20 of those spent teaching at the university level. He’d moved on to a career in publishing, but a casual visit to GIA’s informational booth at the Tucson gem and mineral shows led him back to the classroom – this time, as a student.
King, who worked as a geologist at West Virginia University and the West Virginia Geological and Economic Survey from the mid-1970s through the early 1990s, taught at Pennsylvania State University and Mansfield University of Pennsylvania from the 1980s through 2008. He taught geology, hydrology, global positioning systems and web-based cartography, and served as the director of Mansfield’s Center for Effective Teaching and a content advisor for the Earth and Space Science Education program.
When King approached the GIA booth in 2010, he had already started to consider furthering his own education. He had also begun publishing informational articles on Geology.com, an Earth science news and information website he purchased in 2005 with the intent to help educate the general public and those interested in introductory geology.

“Tumbled stones are the least expensive way to start a gem collection,” says King, who sells a few tons of the stones each year to hobbyists and beginning lapidaries, and even sends them to GIA for identification. “When I took GIA’s Gem Identification course, I was happy to be asked to identify a number of tumbled stones.” Courtesy of Geology.com. Photo by Bradley Cole
“I’d always been interested in gems,” he says. “As I wrote articles about rocks and minerals for Geology.com, many were gem materials, and I’d sometimes include a photo of a cabochon or faceted stone. I noticed the gem photos led to a large increase in visitors, so I started adding more information about gems to those articles. The popularity of those articles increased in page views and how much time they’d spend on the page – my visitors wanted to know about gems! That compelled me to obtain a formal education in gemology so I could write more competently.”
King had been an early adopter of online education, helping Mansfield University of Pennsylvania develop what he believes was “one of the first interactive geology courses in the United States delivered completely online.” He was surprised and pleased to learn that GIA offered Distance Education classes, and enrolled immediately in Colored Stones Essentials, continuing with other GIA Distance Education courses over the next several years.
In 2016, King had a personal breakthrough that made it possible for him to delve even deeper into the world of gemology: new vision.
“Cataract surgery dramatically improved the clarity of my vision and perception of color,” he says. “That motivated me to enroll in GIA’s lab courses, so I decided to take the Colored Stone Grading lab class while visiting California, and returned later for Diamond Grading and Gem Identification.”

King’s team, which works in publishing and e-commerce for Geology.com and RockTumbler.com, includes (from left): Bradley Cole, Amber Cole, King’s sister Laura Rittenhouse, Hobart King, and his daughter Angela King. Courtesy of Geology.com. Photo by Bradley Cole
King, whose interest in geology began as a 6-year-old “prospecting” for invertebrate fossils in his parents’ limestone driveway, earned his Graduate Gemology diploma in 2017 – 42 years after earning his first degree in geology.
“I’m convinced that GIA’s Gem Identification course is one of the finest – if not the finest – distance education course available,” he says. “The entire GG program has to be among the best programs delivered online, and it’s been an important asset for me. It is extremely helpful in my content writing, and provides a credential that separates me from writers who are not writing from formal education and experience.”
The continuing education has helped equip King and his four employees, including his sister and daughter, who also run a lapidary and rock tumbling retail site RockTumbler.com, to better serve the million-plus visitors that Geology.com draws every month.
“A typical visitor might arrive looking for information about rocks, minerals, volcanoes or maps – then, they see an article about a gemstone and read that,” says King, who considers writing educational content for them to be his most important job. “In a way, our website has become an ambassador for gemology, an applied form of mineralogy, one of geology’s core disciplines.”

“As in gemstones, the inclusions of mineral debris in coal is undesirable,” says King, a former geology professor and a GIA GG. “Evaluating coal is similar to evaluating the clarity of gemstones, the difference is mainly a matter of scale.” His image of a “highly magnified view of coal in transmitted light” shows a spore (large yellow object), thin shreds of woody material (red bands), smaller spores and algal debris (orange and yellow particles), and charcoal or opaque mineral inclusions (black material.) Courtesy of Geology.com. Photo by Hobart King
He’s found that researching and preparing Geology.com’s daily news page, for which he aggregates relevant news stories from trade and consumer media, takes the bulk of his work time while also attracting significant engagement from visitors.
“The daily news page is the part most visited by professional geologists, and they engage with stories related to oil, gas and mining,” he says. “Oil and gas, earthquakes, volcanoes and mining stories are the most popular with our overall readers. Knowing what they engage with guides me, and I include a sprinkling of other topics for curious visitors.”
King is fascinated by the “connections and patterns” he finds between news stories.
“With natural gas, for example, when I see topics surrounding discoveries, pipeline projects announcements and liquefied natural gas over a period of months, it helps me make connections and understand the movement of prices and global production, consumption, investment and politics,” he says. “And I hope my readers will see these patterns, too.”
As King has advanced in his own studies of gemology, he’s making connections between gem and jewelry news on JCK daily blogs, for example, and stories in Gems & Gemology and Mining.com.
“Retail, research and mining have many intersections,” he says.
King is endlessly curious, and hopes the accessible, educational content and introductory lapidary supplies his companies provide will inspire others to also develop eager, open minds.
“We learn something new every day,” he says, “and we’ll continue to share as we learn.” @topic:2


Publish Year: 2009 Title: Characterization of Peridot from Sardinia, Italy Abstract: Gem-quality peridot is occasionally found as mantle xenoliths within basalts near Pozzomaggiore, in northwestern Sardinia, Italy. The gemological properties and spectroscopic features of this material are consistent with the measured chemical composition of Fo91Fa9, typical of peridot from other localities worldwide. Although not yet mined commercially, this stone represents a promising gem material. @topic:2


Publish Year: 2018 Title: Natural Emerald with Inclusions Along Three Directions Abstract: Figure 1. This 10.48 ct sugarloaf emerald from Zambia shows a vivid and highly saturated green color. Photo by Yizhi Zhao.

Recently, Guild Gem Laboratories received a 10.48 ct sugarloaf emerald (figure 1) for identification and origin determination. The refractive index (approximately 1.58) and specific gravity (approximately 2.80) fell within the range for beryl, and Fourier-transform infrared (FTIR) testing confirmed it as natural emerald. Additionally, energy-dispersive X-ray fluorescence (EDXRF) analysis revealed Fe, V, and Cr contents consistent with those in Zambian material.

Figure 2. Platy inclusions in the emerald in three directions, intersecting at 60/120 degree angles viewed along the c-axis. Photo by Yujie Gao; field of view 2.8 mm.

Figure 3. Top: The hexagonal inclusions in the basal plane are parallel to the orientation of the platy inclusion described in figure 2. Field of view 3.1 mm. Bottom: A thin layer exhibiting growth lines is perpendicular to the emerald’s c-axis. Photos by Yujie Gao.
The stone showed interference colors when placed under a polariscope with the bottom facing up. With a conoscope, the optic axis of this emerald was determined to be perpendicular to the bottom. Using the microscope, we found thin platy inclusions arranged in three directions intersected with each other at 60/120 degree angles (figure 2). Those inclusions were mainly dark brownish and transparent with well-formed rectangular shapes, some of which exhibited a light bodycolor resembling an unhealed fracture. Evenly distributed reflective light could be seen at certain angles. We deduced that those inclusions had relatively smooth surfaces, which means that their original crystal faces were not corroded during the emerald’s formation. Further observation revealed hexagonal inclusions in the basal plane. Owing to uneven development during their crystalline formation, several of them were nearly triangular in shape. Their sides were parallel to the direction of the platy inclusions (figure 3, top). We also found distinct growth lines near the bottom of the sugarloaf perpendicular to the c-axis. These platy inclusions appeared to be concentrated sparsely in a thin layer with a thickness around 1.5–2.0 mm, as shown figure 3 (bottom). The sparseness of the oriented inclusions resulted in the absence of asterism or cat’s-eye phenomena.

Figure 4. Proposed illustration of hexagonal inclusions in the basal plane and platy inclusions along the prismatic faces. Illustration by Yujie Gao.
Considering the optic axis, we concluded that the platy inclusions grew along the hexagonal prismatic emerald faces, with the hexagonal platy inclusion parallel to the basal plane, as illustrated in figure 4. However, it is still unclear whether they were syngenetic or exsolution, since their well-preserved shapes showed little evidence of corrosion and there was insufficient evidence of exsolution. @topic:3


Publish Year: 2018 Title: GIA’s 2018 Symposium: Up and Away! Abstract: Since GIA’s first International Gemological Symposium in 1982, this event has served as a platform for advancing knowledge in the research and business sides of gemology. For three days, October 7–9, we celebrated the centennial of the incomparable Richard T. Liddicoat by hosting GIA’s sixth Symposium. Nearly 800 attendees from 36 countries gathered in Carlsbad, California, including more than 100 presenters and panelists.
We’ve prepared this special Symposium Proceedings volume of G&G to capture the insights and the spirit of this unforgettable event. Scenes from all three days and nights are shown in the photo montage scenes from all three days and nights are shown in the photo montage.
The Symposium experience began with a powerful opening session featuring The Music Paradigm. Audience members found themselves seated within a live symphony orchestra as maestro Roger Nierenberg offered dynamic lessons on leadership and teamwork. This performance was followed by an opening gala at GIA World Headquarters. On display at the campus were some extraordinary new exhibits assembled by the GIA Museum. This gala was the first of three evening social events for rekindling old friendships and creating new ones.
In the Symposium research track, 37 speaker presentations and 68 poster sessions covered seven important themes: colored stones and pearls, diamond geology, diamond identification, gem characterization, gem localities and formation, general gemology and jewelry, and new technologies and techniques. In the speaker abstracts and the poster abstracts, you’ll find a wealth of informative research summarized. An index of all the presenters appears in the back of the issue.
In a parallel program, classes taught by three professors from the Harvard Business School explored real-life case studies on authentic leadership, customer centricity, and disruptive innovation. Participants gained a deep understanding of these strategic concepts through classroom sessions and discussion groups.
The Symposium’s closing session, the Futurescape Forum, brought together six of the industry’s most influential leaders to forecast what lies ahead as technological breakthroughs, changing consumer tastes, and sustainability concerns continue to reshape the gem and jewelry landscape. You’ll want to read the recap of this lively and thought-provoking panel discussion.
This event would not have been possible without the thousands of hours of planning by the Symposium steering committee and the dedicated efforts of dozens of GIA volunteers, all of whom are recognized on the front and back inside covers of this issue. I am especially grateful to Kathryn Kimmel, GIA’s senior vice president and chief marketing officer, for once again chairing the Symposium and bringing to it her own signature style.
To all those who came to Carlsbad to attend the Symposium, we simply cannot thank you enough for being part of this event. We hope that you came away from it informed and inspired to embrace the future of our great industry. @topic:11


Publish Year: - Title: Fall 2018 G&G: Proceedings from the 2018 International Gemological Symposium Abstract: The 2018 GIA International Gemological Symposium, held October 7–9 in Carlsbad, California, was the sixth such
event dedicated to groundbreaking research across the gem and jewelry industry. A number of presentations discussed
inclusions in gem materials. The cover photo uses differential interference contrast to show the interior scene
of a diamond, where localized areas of high solubility appear as dissolution trigons decorating twin planes in a linear,
crystallographically aligned arrangement. Photomicrograph by Nathan Renfro; field of view 0.83 mm.

In celebration of Richard T. Liddicoat’s centennial birthday, GIA held its sixth International Gemological Symposium October 7–9, 2018, in Carlsbad, California. Nearly 800 attendees from 36 countries convened to exchange groundbreaking gemological research and to examine case studies taught by professors from the Harvard Business School. The Fall 2018 issue of G&G is dedicated to the proceedings of the Symposium. Featured are 37 speaker abstracts and 68 poster abstracts from the research track’s seven themes: Colored Stones and Pearls, Diamond Geology, Diamond Identification, Gem Characterization, Gem Localities, General Gemology and Jewelry, and New Technologies and Techniques.
In Colored Stones and Pearls, keynote presenter Barbara Dutrow considered tourmaline’s role as a geologic timekeeper, while Wuyi Wang began Diamond Identification with the color origin and type Ib designation of canary yellow diamonds. The Diamond Geology session opened with Graham Pearson’s discussion of “unconventional” formation settings, while Evan Smith headlined Gem Characterization by examining the genesis of natural type IIa and IIb diamonds. Lee Groat’s keynote presentation in Gem Localities related the importance of “fingerprinting” chemical analysis to origin determination. In General Gemology and Jewelry, Saleem Ali explored the challenges and emerging opportunities—including education, beneficiation, and environmental remediation—in creating a sustainable mine-to-market colored gemstone supply chain. In New Technologies and Techniques, keynote speaker Daniel Twitchen reviewed advances in the chemical vapor deposition (CVD) process used to create laboratory-grown diamonds.
The poster presentations, on display and available for viewing by attendees for all three days, are also captured in this issue of G&G.
In the closing session, the Futurescape Forum offered an illuminating forecast from six influential leaders in the gem and jewelry industry. The panelists discussed sourcing and production, the online vs. brick-and-mortar store retail experience (including Internet vs. in-person auctions), the impact of laboratory-grown material on the diamond market, and adapting to a millennial workforce.
The Fall 2018 issue also contains a photo montage with scenes captured during the Symposium, from the Music Paradigm opening session to the farewell reception. @topic:8


Publish Year: 2016 Title: GSA 2016 Annual Meeting Abstract: A group shot of presenters in the oral and poster sessions. From left to right, Dr. Evan Smith (GIA), Dr. Christopher M. Breeding (GIA), Paul Johnson (GIA), Mandy Krebs (Univ. of Alberta), Dr. Karen Smit (GIA), Dr. Graham Pearson (Univ. of Alberta), Dr. Raquel Alonso-Perez (Harvard University), Dona Dirlam (GIA), Troy Ardon (GIA), Dr. Emmanuel Fritsch (Univ. of Nantes), Jullieta Lum (Univ. of Johannesburg), Dr. Jeffrey Post (Smithsonian Institution), Dr. Peter Heaney (Penn State University), Dr. Jim Shigley (GIA). Photo by Tao Hsu/GIA

The Geological Society of America (GSA) held its annual meeting September 25–28 in Denver, Colorado. This was the fourth meeting in which GIA hosted gemological technical sessions. In the oral and poster sessions, gemologists, geoscientists, and students from all over the world came together to present their research and discuss advanced topics.

The gemology oral session at GSA has been organized and sponsored by GIA since 2012. This year’s oral session was very well attended. Photo by Tao Hsu/GIA
Invited speaker Jeffrey Post (Smithsonian Institution, Washington DC) presented the results from detailed and sustained studies on a selection of significant fancy-color diamonds, including blue, pink and chameleon stones. Among these, the researchers applied time-of-flight secondary ion mass spectrometry (ToF-SIMS) analysis to the Hope diamond, which allowed the measurement of total boron concentration; the results revealed strong zoning from this chromophore in many blue diamonds. Graham Pearson (University of Alberta, Canada) reported on his study of the saline fluid inclusions preserved in some diamonds from the Ekati and Diavik mines and pointed out that alkali- and Cl-rich fluids play a key role in diamond formation. Invited speaker Emmanuel Fritsch (University of Nantes, France) discussed the state of synthetic diamond identification. He also noted the advantages and limitations of some of the most commonly used sorting methods.

Dr. Evan Smith from GIA reported his exciting inclusion findings in large top quality type IIa diamonds. Photo by Tao Hsu/GIA
GIA researchers shared their results on several diamond-related projects. Christopher M. Breeding showed the fluorescence colors and patterns diamonds can display when exposed to ultraviolet light. In addition to their beauty, these colors and patterns are important in diamond formation studies and the identification of natural, treated, and synthetic material. Karen Smit presented new data on a suite of canary diamonds from Sierra Leone. This will allow researchers to further specify the source fluids and color-forming defects of these yellow diamonds and better correlate their features to the unusual geological formation history of the Zimmi diamond deposit. Evan Smith reported his findings on inclusions in thousands of high-quality type II polished diamonds and trimmed-off portions. The recurring set of inclusions in many stones includes a metallic multi-phase assemblage and retrogressed former perovskite phases. Together, the two inclusion types revealed a unique paragenesis for these large, top-quality diamonds.

Dr. Jim Shigley (left), Dona Dirlam (center), and Dr. Wuyi Wang (right) have been the advocators for gemological technical session in GSA annual meetings for the past four years. Photo by Cathy Jonathan/GIA
Presentations on colored gemstone research revealed a variety of studies on important gem species and collector stones. Mandy Krebs (University of Alberta) reported on Pb-Pb geochronology of rubies and the first-ever radiometric age determination of ruby. This new method allows dating to be done directly on the ruby itself rather than on inclusions such as zircon. This dramatically broadens the application of geochronology in ruby provenance determination. Jullieta Lum (University of Johannesburg) presented major and trace element composition of emerald and aquamarine collected from central Namibia and South Africa. Peter Heaney (Penn State University) revealed the cause of iridescence in metamorphic hematite from Minas Gerais, Brazil. The study by Dr. Heaney and his former student Xiayang Lin found that this phenomenon is caused by a framework of well-oriented hematite nanorods. Raquel Alonso-Perez (Harvard University) presented preliminary results on the geochemistry of emeralds from the Irondro deposit in Madagascar.

Dr. Raquel Alonso-Perez from Harvard University reported the preliminary geochemistry study on emeralds from Madagascar. Photo by Tao Hsu/GIA
Important research on gemstone formation was also delivered. Yury Klyukin (Virginia Tech) addressed the valuable information fluid and melt inclusion studies can provide in solving gem formation problems, using diamond, emerald, and corundum as examples. Invited speaker David London (University of Oklahoma) discussed the different mechanisms that caused zonation within pegmatites. Understanding of mineral segregation within pegmatites is critical for gem exploration.

Dr. Graham Pearson discussed the results from fluid inclusion study performed on diamonds from Ekati and Diavik. Photo by Tao Hsu/GIA
The poster session presenters included two graduate students from the China University of Geosciences (Wuhan). Chengsi Wang proved the robustness of photoluminescence (PL) spectroscopy in treated and synthetic spinel identification through a series of heating and annealing experiments. Yuan Zheng applied linear discriminant analysis (LDA) in separating hundreds of turquoise samples from three different sources after analyzing their trace elements using ICP-MS.

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Poster Session
GIA diamond researchers and library staff also presented interesting discoveries in the poster session. Wuyi Wang studied the distribution of the [Si-V]– defect and found that it has a dramatically different correlation with Nii+ between natural and HPHT synthetic diamonds. Paul Johnson demonstrated that hydrogen-rich diamonds with intensive inclusions and fractures can be heated to generate a more uniform black color. Based on his experience, microscopic observation remains the most powerful tool in identifying this treatment. Troy Ardon and Sally Eaton-Magaña conducted a series of annealing experiments at different temperatures with two hydrogen-rich Zimbabwe diamond plates. They evaluated the effect of high temperature on the diamonds’ spectroscopic features and inclusions. Rose Tozer examined one of the rarest publications in the GIA library collection: Russia’s Treasure of Diamonds and Precious Stones. Edited by the well-known mineralogist A.E. Fersman, this book documents Russia’s regalia and crown jewels at the time of the February Revolution in 1917. The volume has been digitized as part of GIA’s project to digitize items from its rare book collection and can be accessed free of charge at https://archive.org/details/gialibrary.

The science discussion continued at the GIA hosted dinner reception. Presenters, guests and GIA Denver alumni attended this reception. Photo by Tao Hsu/GIA
Abstracts from the two gemological sessions can be found at https://gsa.confex.com/gsa
/2016AM/webprogram/Session40327.html (oral) and https://gsa.confex.com/gsa/2016AM
/webprogram/Session41331.html (poster). The 2017 meeting will be held October 22–25 in Seattle.

The 2017 GSA annual meeting is going to be held in Seattle, Washington. GSA will again host both oral and poster technical sessions. Photo by Tao Hsu/GIA @topic:8


Publish Year: 2016 Title: Multiphase Fluid Inclusions in Blue Sapphires from the Ilmen Mountains, Southern Urals Abstract: Figure 1. Map showing the location of the blue sapphire occurrence within Russia.
Most gem-quality sapphires are found in placers that originate from the weathering of primary deposits. Discovering a mineral in situ, or within the host rocks, is rare. In August 2015, some of the authors visited a corundum deposit in the Ilmen Mountains in the southern Urals of Russia (figure 1) to collect the stones in situ for research. This is a primary source where blue sapphire megacrysts are found exclusively in syenite pegmatites. The occurrence is located inside the Ilmen State Reserve, and its commercial exploitation is forbidden.

Corundum syenite pegmatites in the Ilmen Mountains present an REE-rich source of transparent to translucent blue sapphire crystals measuring up to 5.9 × 4.2 cm (figure 2). But the brittle deformation throughout the gem-bearing rocks, which appears to be linked to syntectonic and post-tectonic processes that occurred at the deposit and the surrounding area, increased the amount of fissures in the corundum. As a result, the sapphires are of a lower quality and can only be faceted into small stones. Six sapphire wafers and nine petrographic thin sections of mineral from corundum-bearing rocks of this occurrence were recently examined at GIA’s Carlsbad lab.

Figure 2. Sapphire crystals in feldspar matrix of a syenite pegmatite from the Ilmen Mountains of Russia. The largest sapphire crystal measures 5.9 × 4.2 cm. From a private collection; photo by Elena S. Sorokina.
Laser ablation–inductively couple plasma–mass spectrometry (LA-ICP-MS) and electron microprobe analysis (EPMA) indicated medium-rich Fe (2470–3620 ppmw), high Ga (190–280 ppmw), and low Mg (3–9 ppmw) with Ga/Mg 29, all in the range of magmatic sapphires (see J.J. Peucat et al., “Ga/Mg ratio as a new geochemical tool to differentiate magmatic from metamorphic blue sapphires,” Lithos, Vol. 98, No. 1–4, 2007, pp. 261–274).

Ferrocolumbite, zircon, and alkali feldspar group minerals, identified by confocal micro-Raman spectroscopy, were observed as syngenetic inclusions. Epigenetic muscovite and exsolved needles (most likely ilmenite) were found as well; along with syngenetic inclusions, they are common phases in mineral assemblages of Ilmen corundum syenite pegmatites (see V. F. Zhdanov et al., “The mineralogy of corundum pegmatite pit no. 298 of the Ilmen State Reserve,” Materialy k mineralogii Yuzhnogo Urala [Materials to Mineralogy of South Urals], AS USSR, 1978, pp. 92–97, in Russian). Wafers 200–400 µm in width were prepared in order to study fluid inclusions (FI) trapped within the sapphire crystals.

Using Raman spectroscopy, solid phases in needle and thin-film form were identified as diaspore (figure 3); both vapor and liquid phases were found to be CO2, with a Fermi doublet for the liquid phase at 1282.9–1283.2 and 1387.2–1387.6 cm–1, accompanied by less intense symmetrical bands (“hot bands”; see N.B. Colthup et al., Introduction to Infrared and Raman Spectroscopy, 2nd ed., Academic Press, New York, 1975) at approximately 1264 and 1408 cm–1 and a small band at 1370 cm–1 due to 13CO2. Raman spectra in the 2000–4000 cm–1 range did not show H2O-, CH4-, or N2-related bands. The less intense apparent maxima at 418, 578, and 750 cm–1 belong to sapphire vibration modes. The distance between Fermi doublet peaks (Δ) ranged from 104.1 to 104.4 cm–1 (again, see figure 10), occurring at about 0.7 g/cm3 CO2 density (see X. Wang et al., “Raman spectroscopic measurements of CO2 density: Experimental calibration with high-pressure optical cell (HPOC) and fused silica capillary capsule (FSCC) with application to fluid inclusion observations,” Geochimica et Cosmochimica Acta, Vol. 75, 2011, pp. 4080–4093). The distance was linked to the pressure at approximately 1.8 kbar for the trapping of fluid inclusions within the sapphire matrix (CO2 P-T isochores, or lines of constant density). The CO2 homogenization temperature (the temperature at which the fluid inclusion becomes a single-phase liquid or vapor) occurred in the liquid phase and measured between 30.1° and 30.7°C (figure 4), while the corundum-diaspore equilibrium was estimated at 510°–530°C (matching the previous estimation by V.A. Simonov, Usloviya mineraloobrazovaniya v granitnykh pegmatitakh [Conditions of Mineral Formation in Non-Granitic Pegmatites], Nauka, Novosibirsk, USSR, 1981, in Russian). Based on the determined pressure (around 1.8 kbar), the temperature of stability for the corundum-orthoclase-H2O system was higher than 690°C (H.S. Yoder and H.P. Eugster, “Synthetic and natural muscovites,” Geochimica et Cosmochimica Acta, Vol. 8, 1955, pp. 225–280), likely linked to the multistage geological history of blue sapphire crystallization along the P-T path in the Ilmen Mountains.

Figure 3. Raman spectra at room temperature of a fluid inclusion trapped in a sapphire
from the Ilmen Mountains: 12CO2 Fermi doublet along with hot bands and 13CO2 peak
(red trace), diaspore needle (blue), and a diaspore thin film (green). For 12CO2, the
average distance between Fermi doublet peaks (Δ) was calculated as 104.25 cm–1.
Diasp = diaspore, Sph = sapphire, Ilm = ilmenite, l = liquid CO2, v = vapor CO2.
Photomicrograph by Elena S. Sorokina; polarized transmitted light, field of view 0.288 mm.

Figure 4. Homogenization of CO2 in a fluid inclusion in sapphire from the Ilmen Mountains occurs in the liquid phase between 30.1° and 30.7°C. A: Homogenization of CO2 above 30.7°C. B and C: Vaporization of CO2 with a temperature below 30.7–30.1°C. D: The multiphase FI at room temperature. l = liquid, v = vapor. Photomicrographs by Jonathan Muyal; transmitted polarized illumination, field of view 0.72 mm.
Further study of these sapphires is needed to better understand the geological history of this locality, but the information obtained can provide valuable clues about the characterization of gem corundum from secondary placers. @topic:1


Publish Year: 2016 Title: The Fluid Art of Angela Conty Abstract: Figure 1. This pin/pendant features two Oregon sunstones, a Chinese freshwater pearl, and diamond accents. Carved green chalcedony and a 1.50 ct zircon complete the design. The piece is set in 14K and 18K yellow gold. Photo by Robert Weldon/GIA; courtesy of Angela Conty.

Renowned lapidary, designer, and goldsmith Angela Conty created a jewelry collection exclusively for the 2016 Tucson gem and mineral shows. We had a chance to see some of her convertible pieces at the Hotel Tucson City Center.

Ms. Conty’s artistic vision is heavily influenced by nature: Flowers, leaves, twigs, seed pods, and similar motifs are reflected in her work. The fluidity of her artistic expression strikes a perfect balance and flow between the gemstone carving and the jewelry design. Ms. Conty views her design and manufacturing process as the evolution of a work of art that often features a carved gemstone. Changes may occur when carving the stone, working the metal, or assembling the piece of art. When she has the rough in hand, she takes into consideration the stone’s shape, its best orientation, and how it would look carved and set in jewelry. As the carving progresses, the rough might take an unexpected direction, even after the metalwork is finished. She feels that lapidary work and metalsmithing must blend and harmonize in order to create the perfect balance. This means the carving or the metalwork can be continually adjusted until the carving is ready to be set. In her words, “I gather together elements, cast and constructed, and begin to solder or weld until the carving, gemstones and metalwork begin to work together, always ready to make more changes. I add, move, and remove elements to create a better integration of carving and goldwork.”

Her gemstone preferences include Australian opal, quartz, chalcedony, and her new favorite, Oregon sunstone. Her metal of choice is 18K gold, but she will sometimes use silver or 14K gold, depending on the design or the client’s preference. The relationship between the stone and metal is beautifully demonstrated in the Oregon sunstone jewelry pieces shown in figures 1 and 2, which can be worn as either brooch or pendant.

Figure 2. This 18K yellow gold convertible pendant/pin features a 46.80 ct carved Oregon
sunstone as its centerpiece. A chocolate Tahitian pearl drop and diamond accents help
frame the carving. Photo by Robert Weldon/GIA; courtesy of Angela Conty.
Ms. Conty’s combined talents in art and creative design took root more than 40 years ago at the State University of New York (SUNY) at New Paltz, where she earned undergraduate and graduate degrees in art. Her training included drawing, art history, painting, ceramics, sculpture, and silversmithing. She studied metalwork under Kurt Matzdorff, the founder of the Society of North American Goldsmiths (SNAG), and is a self-taught lapidary artist.

In 2002, Ms. Conty won second place in AGTA’s Cutting Edge Awards in the Objects of Art category. Her work has been featured in numerous publications and books. @topic:6


Publish Year: 2015 Title: Color Zoned Emerald Abstract: Figure 1. Left: When table-down, the stone is mainly colorless, showing some partially green overgrowth. Right: Face-up, the faceted stone displays an even and attractive dark green emerald color. Photos by Jonathan Muyal.

Cutting style and orientation are important considerations when cutting natural crystals with strong color zoning. Careful placement of these zones can distribute color by reflection, creating a uniformly colored finished stone when viewed face-up.

Recently, the Carlsbad laboratory received a 33.73 ct green octagonal step cut showing strong color zoning (figure 1). The gem cutter skillfully placed a thin green color zone in this emerald along the pavilion facets so that the stone would appear uniformly green when in a face-up position. Standard gemological testing revealed a refractive index (RI) of 1.571–1.578 and a specific gravity (SG) of 2.72. Chromium-related features were observed in the red end of the spectrum when examined with a handheld spectroscope. All of these properties were consistent with emerald. During microscopic examination, minute jagged fluid inclusions and growth tubes were observed, proving the stone was of natural origin (figure 2).

Figure 2. When viewed from the side, irregular green color zoning is observed along with
minute jagged fluid inclusions. Photomicrograph by Jonathan Muyal; field of view 14.52 mm.
Interestingly, the stone showed a strong green color zone very close to some of the pavilion facets, as well as hexagonal columnar-like growth and irregular zoning (figure 3). This type of zoning represents a late-stage influx of chromium and vanadium into the genetic environment, which were then incorporated into the crystal lattice of the beryl. Energy-dispersive X-ray fluorescence (EDXRF) revealed high levels of Cr and V in the green color zone, which was consistent with the observed color. Although similar zoning has been observed in emerald previously (E.J. Gübelin and J.I. Koivula, Photoatlas of Inclusions in Gemstones, Volume 3, Opinio Verlag, Basel, Switzerland, 2008, pp. 433–434), the zoning in this specimen was quite distinct.

Figure 3. The colorless spots indicate parallel columnar growth of white beryl overgrown
by green emerald. Photomicrograph by Jonathan Muyal; field of view 19.27 mm.
This emerald demonstrates the significance of proper orientation and cutting style in fashioning high-quality gem materials. @topic:3


Publish Year: 2015 Title: Larger Optic Disks Abstract: Nature’s Geometry

In this video, Brian Cook explains the next step in the evolution of his unique optic disks: larger pieces that display a striking rainbow of concentric color bands.
At the 2014 GJX show, Brian Cook (Nature’s Geometry, Graton, California) showed us innovative optical disks made of colorless quartz featuring a drilled tube containing pieces of brightly colored gem and mineral rough. The tube is subsequently sealed with clear quartz. When the disk is viewed face up, the insert’s reflections permeate the disk with bright color.

For this year’s show, Cook’s “wheel of light” design evolved into larger sizes with more intriguing reflective effects. Seen front-on, the new disks produced concentric colored reflections. The first we saw measured approximately 4 cm (1.57 in.) in diameter and featured Brazilian emerald, Paraíba tourmaline, and haüyne insets (haüyne is a brittle sodium calcium sulfate that provides rich blues). One innovative feature is that the viewer could see different colors depending on the viewing direction. From various directions the disk was suffused with bands of rich green, electric blue, or royal blue color.

According to Cook, this new product takes the color and amplifies it. There is a chamber within the quartz, which he polishes before inserting the colors he wants. Because no faceting is involved, all the colors are blended together. Cook said his passion for Paraíba tourmaline was the starting point.

Figure 1. This edge-on view of the “wheel of light” reveals its construction. Photo by Duncan Pay/GIA; courtesy of Nature’s Geometry.
Cook unwrapped a larger disk, approximately 8 cm (3.15 in.) in diameter. Viewed edge-on, the chamber’s pattern of colored rough gems and minerals was revealed (figure 1). Cook had arranged a complete spectrum of rainbow colors in sequence: ruby, spessartine garnet, a gold nugget, Paraíba tourmaline, and haüyne (figure 2).

Figure 2. Seen end-on, the larger disk displays the spectrum as concentric colors. Photo by Duncan Pay/GIA, courtesy of Nature’s Geometry.
Cook also showed us a smaller optic disk set in a handmade platinum pendant set with diamond and melee-size Paraíba tourmaline from the Brazil Paraíba mine in Parelhas, Rio Grande do Norte. This piece combined the unusual optic effects of the center, which featured more Paraíba tourmaline and haüyne, with a conventional suite, which besides the pendant included a pair of earrings set with similar optic disks. @topic:3


Publish Year: 2015 Title: Fine Corundum, Demantoid Garnet Abstract: Figure 1. This unheated 8.56 ct intense pink sapphire represents the very best of recent production from Madagascar. Photo by Robert Weldon/GIA; courtesy of B&B Fine Gems.

At the AGTA show, Dave Bindra (B&B Fine Gems, Los Angeles) showed us some exceptional corundum, especially fine untreated yellow and pink sapphires.

The first standout piece Bindra showed us was an 8.56 ct unheated, intense pink sapphire of extremely high clarity from Madagascar. Under the lights of our photo studio, it showed an intense pink hue (figure 1). A gem of this quality might expect to realize a wholesale price in the region of $10,000 to $15,000 per carat. Bindra noted that Madagascar is producing some superb fancy sapphire, including pink, violet, and “padparadscha” colors.

	B&B Fine Gems

In this interview, Dave Bindra of B&B Fine Gems showcases fine pink and yellow sapphire, Mozambique ruby, and a superb suite of Russian demantoid garnet. He explains how increased consumption in markets outside the U.S. and Europe is affecting gem supply and forcing many colored gem dealers to turn to the “recirculated” market for their clients.
Although this pink gem represented recent production, Bindra explained that the secondary market has become an extremely important source for many dealers now that competition for freshly mined goods is so intense, particularly from buyers serving Asian markets. These recirculated gems coming back onto the market offer a way for dealers to procure stones that often surpass current production in size and quality, or are simply unobtainable today. As an example, Bindra cited an 89.55 ct unheated golden sapphire from Sri Lanka (figure 2), remarking that he had not seen material of this color emerge from the ground in Sri Lanka for more than 10 years. Originally this gem was somewhat larger, over 100 ct. Modern cutting reduced the weight slightly but produced a dramatic improvement in color and brilliance. Bindra described this gem’s appearance and stature as “world class.” As such, it would likely command a wholesale price in excess of $3,000 per carat.

Bindra next showed us a blend of new production and recirculated stones: a graduated suite of 12 perfectly matched Russian demantoid garnet round brilliants. Each gem contained a classic “horsetail” inclusion. Weighing in at 20 carats total, the suite took Bindra four years to complete. He described it as a special item, with the stones from the secondary market selected and recut to perfectly match the newer gems.

Figure 2. This exceptional unheated 89.55 ct golden sapphire from Sri Lanka is an example of a recirculated stone. Photo by Robert Weldon/GIA; courtesy of B&B Fine Gems.
For Bindra, Mozambique is the future of ruby production. He illustrated this with three fine heated gems from the Montepuez deposit weighing 7.05, 7.92, and 9.35 ct (figure 3). Although all three stones represented beautiful, clean material, he considered the 7.92 ct gem the finest, due to its superior brilliance and intense red hue. Due to the ongoing trade embargo with Myanmar, classic “Burmese” ruby is unobtainable for U.S. dealers. Fine Mozambique rubies like these in the 7–9 ct range are in high demand and exceptionally rare. Gems larger than 4 or 5 ct are increasingly hard to find, Bindra pointed out.

Figure 3. Left to right: These heated rubies from Mozambique weigh 7.05, 7.92, and 9.35 ct. Photos by Robert Weldon/GIA; courtesy of B&B Fine Gems.
Unlike Myanmar, Mozambique does not carry the stigma of human rights abuses. The heat treatment of these rubies is not an issue with consumers, either. As Bindra explained, the market for top natural unheated ruby has now reached such rarified levels that buyers are very receptive to high-quality heated rubies. (The current auction record is held by an unheated 8.62 ct Graff ruby, of Burmese origin, which sold for $8,372,094—or $994,040 per carat—at a Sotheby’s Geneva auction in September 2014.) Purchasing such expensive stones is a stretch even for the top 1% of consumers. By contrast, stones like the three Bindra showed us wholesale in the region of $35,000 to $50,000 per carat. He said gems like these are “quite consumable” and can be the centerpieces of wearable jewelry, meaning they will occasionally be seen outside of safe deposit boxes.

Bindra faces the same issue as many other colored stone dealers in Tucson: scarcity of new rough production due to intense competition between the U.S. market and buyers purchasing for Chinese consumers. This is the major driver for dealers looking for alternative sources of gems such as recirculated goods, he said.

The new wealth in China has created a different dynamic. For more than 50 years, American and European consumers have been the main buyers of fine gemstones, he explained. Now these established markets have competition, and Bindra and many of his colleagues in the business supply gems to these competitors as well. Besides China, other cultures—India, for instance—have a rich jewelry heritage, and consuming gems is ingrained. This trend is not going to change, so there will be more wealthy consumers in emerging markets that desire colored gems, and current producers will struggle to meet demand.

In terms of demand at the show, Bindra reported that rubies and unheated sapphires were quite strong. There was demand for anything rare and exotic, goods that the average consumer would not find elsewhere. He also saw renewed demand for emerald. In the past, he noted a “certain favoritism” toward Colombian emerald, but increased supplies of quality gems from Zambia have made it a much more popular source and established the “Zambian brand” in people’s minds. @topic:9


Publish Year: 2015 Title: Tucson 2015 Overview Abstract: Figure 1. Many sellers at Tucson were displaying very large, fine, or unusual gems that had been held in inventory for years. Photo by Duncan Pay/GIA; courtesy of Noor Gems Japan Ltd.

Once again, buyers and sellers from all over the world converged on a corner of the American Southwest for the annual Tucson gem shows. Many broad trends continued from 2014: Consuming markets are hungry for fine colored gems, and demand still outstrips supply, causing prices for some gems to reach new highs. As more buyers from Asia compete for new production of rough gemstones, the secondary market is becoming more important for domestic dealers. Many recycled gems and jewelry pieces were returning to the market through estate sales, or directly from owners lured by all-time high prices. Some sellers were showing items that had been held in inventory for years or even decades (figure 1). These included fine corundum, Imperial topaz, red spinel, and aquamarine. We noted that many of these “recirculated” goods were exceptional gems, superior to newly mined production. Many vendors are unable to source new production at prices their clientele are prepared to pay.

Cultured pearls of every type were in high demand—especially from the Chinese market. The same was true of rubellite and “watermelon” tourmaline, tsavorite, and spinel, especially red to pink material from Mahenge, Tanzania.

Overall, we observed several clear trends:

Many gem-quality stones were cut in nontraditional shapes such as cabochons, fantasy cuts, carvings (figure 2), and even slices.
Many jewelry pieces had an organic, natural feel. Similarly, non-round pearls—particularly large baroque shapes—were also everywhere. The freeform shapes of many opals also fit well with natural-shape trends for jewelry, lending themselves to carved flowers, animals, and abstract pieces.
Designers were seeking out unusual colors for standard gems: fancy-color sapphires, colored diamonds, tourmalines, spinel, garnets, zoisite, zircon, and beryl (morganite was very much in demand).
Many vendors told us they left their “traditional” inventory items at home, as they can sell those at any time. The Tucson crowd demands the unusual (figure 3), so vendors brought nontraditional items and were reportedly selling them at a good pace.
Even though red-brown “Marsala” was named the Pantone color of the year for 2015, it did not appear to be an overall favorite, with the most observed colors being bright blues, greens, and pinks.
The largest crowds observed at the wholesale shows were gathered at the booths selling nontraditional gem materials such as cabochons, druzy, tourmalinated and rutilated quartz (again, see figure 2), and crystal slices—material typically used in “craft” jewelry.
Opal (figure 4) was prominent: There was an abundance of Ethiopian hydrophane opal, Australian opal, Mexican fire opal, and material from the U.S. Recent finds in Ethiopia have generated a buzz for all types, according to several vendors.

View Gallery

Figures 2-4
Foot traffic at the main AGTA and GJX shows appeared down from 2014, but most merchants reported brisk sales, especially of very fine or unique items. In fact, many vendors mentioned that this was their best show in recent years. Eric Braunwart of Columbia Gem House (Vancouver, Washington) said he had forgotten what a “good year was like” until this show.

Alexander Wild (Wild & Petsch Lapidaries, Kirschweiler, Germany) provided a broad-brush market update from his firm’s perspective. Rough prices for many gems continued on an upward trajectory, he reported. Just a few years ago, fine-color, high-clarity rubellite tourmaline sold at wholesale for $300 to $350 per carat. These numbers reflected the asking price for superb quality, with perhaps just a few tiny inclusions. In 2015, prices for equivalent material are almost triple that figure.

As in the previous year, sourcing rough gems remains a problem, although it is by no means impossible for established companies with good connections in source countries, such as Wild & Petsch. The company is able to source quality rough, though prices are definitely higher for many goods. Since mid-2014, prices for many other commodities such as oil and copper have fallen. But gemstone rough prices continue to rise, largely due to demand from China. In Wild’s opinion, such high prices are unsustainable. He wondered how long this would continue, asking rhetorically, “Is this a gem bubble?”

Asked what was in demand, he answered that it was the gemstones Wild & Petsch is known for: fine tourmaline and beryl. With their African connections, they secured a nice production of Paraíba-type copper-bearing tourmaline from Mozambique, along with good parcels of aquamarine. As a result, they were able to offer their clientele this material at what Wild considered very fair market prices. In contrast, supply of rubellite and pink tourmaline rough is quite difficult, and most of his supply has been coming from Nigeria. Brazilian rubellite is basically unavailable.

Figure 5. The Cruzeiro mine, the Miranda Group, and KGK work together to bring Brazil’s bicolor and rubelite tourmaline to the market in China. The Cruzeiro mine provides the rough to the Miranda Group, which cuts the material. Photo by Andrew Lucas; courtesy of Miranda Group Co. Ltd.
[Editor’s note: In a 2014 visit to Brazil’s Cruzeiro mine in Minas Gerais State, a GIA team witnessed recovery of large facet-grade rubellite crystals (figure 5), which were all put aside for exclusive sale to a consortium—composed of the Miranda Group and KGK—that fashions the material at its own factory in Shenzhen, China, for the Chinese market (figures 6 and 7). Only blue to green production was available for sale to local and export markets.]

Figure 6. Rough tourmaline crystals are sliced or sawn by the Miranda Group in Hong Kong, then faceted and polished at their factory in Shenzhen. Photo by Andrew Lucas; courtesy of Miranda Group Co. Ltd. (VRL: 179216)

Figure 7. Fine Brazilian rubellite tourmaline at the Miranda Group’s factory in Shenzhen—most of these cut stones are larger than 10 ct. The factory needs to receive 100 kilos of rough per month to meet production goals of 25,000 to 30,000 carats. KGK markets and sells the cut stones and also mounts them into jewelry for sale, primarily in China. Photo by Andrew Lucas; courtesy of Miranda Group Co. Ltd.
Adjusting to price fluctuations has always been part of life for colored stone merchants, Wild conceded, but not sudden, successive increases to levels that are three, four, or five times higher than the market was previously accustomed to (see www.gia.edu/gia-news-research-miranda-journey-of-rubellite-tourmaline).

Wild offered the possibility that at some point a single market will be satisfied—even one as large as China’s. When that happens, suppliers will have to find other markets for these goods. Wild believes the North American and European markets are more sophisticated in terms of pricing—especially for cut goods—than China’s current market. There is also the possibility that any political upheavals there could cause rough prices for certain gems to go down sharply, he said. And that could spell trouble for some miners who base their operations on today’s historically high rough gem prices.

Wild said business at the 2015 show had been better than the year before. He reckoned business was a third above 2014, with some big-ticket items—including a fine aquamarine suite—spoken for prior to the show. He confirmed our impression that traffic was down slightly from last year—possibly due to fewer Asian buyers or the winter travel difficulties on the U.S. East Coast.

Wild intimated that many clients came with specific requirements in mind, particularly aquamarine or Paraíba-type tourmaline, and selection was good for these gems at this year’s show. He mentioned they had even sold a few collectors’ pieces, including a beautiful large green step-cut beryl that measured more than 200 ct. That was a surprise to him, because such items have proven more difficult to sell the last few years.

“Everyone is searching for good things,” Wild concluded. “For the most part, we get what we need.” Asked if the trend is still toward finer, more unique pieces, Wild responded, “Absolutely. I think quality still comes first. A lot of the trends from last year still apply, and we’re still waiting to see if there’s going to be any deflation in pricing for some goods.”
Once again, G&G greatly appreciates the assistance of the many friends who shared material and information with us this year, with special thanks to the American Gem Trade Association for providing photography studio space during the AGTA show. Dr. Tao Hsu, Andy Lucas, Donna Beaton, Pedro Padua, and Dr. Jennifer Stone-Sundberg contributed to these reports. @topic:11


Publish Year: 2013 Title: Faceted Wurtzite from Tanzania Abstract: Figure 1. These wurtzites are from Merelani, Tanzania. The crystal measures 17 mm across, and the cut stones weigh 1.74 and 1.59 ct. Photo by Jaroslav Hyršl.

Wurtzite is the hexagonal polymorph of ZnS. It is far less common than sphalerite, the cubic polymorph of ZnS. All previously identified wurtzite has been opaque to translucent, and therefore not facetable. Layers of wurtzite and sphalerite can alternate in so-called Schalenblende, a colloidal sphalerite variety used only rarely for cabochons. The first transparent wurtzite crystals were found in 2012, at the tanzanite deposit at Merelani Hills, south of Arusha, Tanzania (for identification, see www.rruff.info). The crystals, which measure up to 2 cm in diameter, are very rare. They have a tabular shape, with pyramidal faces. Some crystals from Merelani have clean parts, and several gemstones were faceted from them (figure 1).

Eight cut stones weighing 0.30–1.74 ct were studied. They were orange-brown, with a submetallic luster and very weak, almost invisible, pleochroism. Refractive indices of these stones were well over the refractometer limit, listed as 2.36 and 2.38 in the literature (J. Bernard and J. Hyršl, Minerals and their Localities, Granit, Czech Republic, 2004, p. 666). They had very low birefringence, confirmed by a lack of doubling of facet edges. The determined specific gravity values of two of the crystals were 3.78 and 3.85; their measured hardness was 3.5. The stones were uniaxial positive and inert under both long- and short-wave UV. Their UV-Vis-NIR spectrum (figure 2) exhibited a high cut-off at 545 nm. The stones showed anisotropic crystals and hexagonal growth structures when viewed under a microscope. Because of the rarity and high value of the Tanzanian crystals, the faceted wurtzites are sure to catch the attention of gemstone collectors.

Figure 2. The UV-Vis-NIR spectrum of a 1.74 cut wurtzite from Tanzania. @topic:1


Publish Year: 2014 Title: Tucson 2014 Overview Abstract: View Gallery

Tucson draws buyers hungry for Earth’s treasures.
Every February, exhibitors and buyers from all over the globe descend on Tucson, Arizona, for the annual gem and mineral shows that take place in conference spaces, tents, hotel rooms, and parking lots across the city. This year a number of exhibitors noted the lack of Chinese buyers, who are now likely to make their purchases at the Hong Kong show for convenience. For many exhibitors, however, Tucson remains a very important venue in the year’s trade show calendar.

For Alexander Wild (Wild & Petsch Lapidaries, Kirschweiler, Germany), the show was a place to write invoices and do “serious selling.” While many clients were not shopping for any one particular gem, they were seeking out unique items: fine-quality gems as single pieces, matched pairs, sets, or suites. Exhibitors selling everything from cultured pearls to unheated tanzanite, Australian chrysoprase, and top-quality ruby, sapphire, and emerald echoed the same sentiment: fine goods were strong sellers.

Wild attributed the current shortage of gem rough to the global economic crisis that began in September 2008. The following years, he recalled, were “disastrous” for many in the colored gem trade, as their customers simply stopped buying. The resulting lack of liquidity cascaded down to active mining operations, especially in Africa and Brazil. Miners in those areas were left with no clients for their previously mined goods, and no income with which to purchase equipment or staples such as diesel fuel. Within a short time, Wild said, many operations were saddled with debt and subsequently ceased operations. Mine workers returned to the agricultural sector, which began to rebound in 2009. By then, costs had become so prohibitive that many former operators could no longer afford to return to the mining industry.

	Hans Juergen AlthoeferEmil Kreis & Co.

Hans Juergen Althoefer of Emil Kreis and Co., explains how changes in the colored stone market are reflected in the stock his company carries. While business was formerly concentrated on smaller calibrated goods, clients now demand more unique ‘one-of-a-kind’ pieces along with matched pairs and sets.
One common refrain among exhibitors was the intense competition for scarce cutting rough, creating a dramatic price increase. Many mentioned stiff competition from Chinese buyers or their agents at the sources. Steve Ulatowski of New Era Gems (Grass Valley, California) told us the price of pink to red tourmaline rough has shot up due to Chinese demand. He cited Nigerian tourmaline rough that was priced at $8,000 per kilogram several years ago; the current asking price for equivalent goods was $200,000 per kilo, with sellers asking for cash on the table.

Many dealers also emphasized the importance of “recirculated” gems or jewelry pieces, remarking on the high quality of pieces in the secondary market. These included fine sapphire, ruby, alexandrite, and cat’s-eye chrysoberyl, gems that were otherwise unobtainable. All find a ready market in Asia.

Regardless of these powerful undercurrents, most of the exhibitors who spoke with us expressed satisfaction with their results from Tucson. Although traffic at some shows was down from previous years, exhibitors reported that buyers were serious and business was satisfyingly brisk.

All in all, the Tucson gem and mineral shows are a fascinating cross section of materials, sellers, and buyers that provides a unique window into a singular industry. We eagerly look forward to next year’s shows.

G&G appreciates the assistance of the many friends who shared material and information with us this year, with special thanks to the American Gem Trade Association for providing photography studio space during the AGTA show. GIA’s Eric Welch, Pedro Padua, Clara Zink, and Andy Lucas contributed to this report. @topic:11