Publication Year: 2013 Title: Strain-Induced Birefringence in Natural Diamond: A Review Abstract: Diamond belongs to the cubic crystal system and should therefore exhibit isotropic optical properties. But it is well documented that diamonds often show weak birefringence. This study has focused on the causes of strain-induced birefringence in natural diamonds: dislocations, lattice parameter variations, inclusions, fractures, and plastic deformation.

Strain patterns shed light on the internal stresses within the stone, which in turn reveal the growth and transport history of the diamond. The imaging of diamonds between crossed polarizers remains a simple and rapid technique for obtaining visual information on strain patterns in diamonds.

Abstracted by Guy Lalous @chapter:11


Publication Year: 2015 Title: Analysis of Melee Diamonds Using FTIR Spectroscopy Abstract: Figure 1. This 0.00054 ct colorless round brilliant was submitted for identification as a natural or synthetic diamond. Despite the specimen’s small size, an FTIR microscope can focus a beam through the facets to capture a high-quality infrared spectrum. Photo by Jian Xin (Jae) Liao.

The jewelry industry has expressed increasing concern over the possibility of treated or synthetic diamonds being mixed in with natural melee goods (those weighing less than 0.20 ct). Recently, GIA’s laboratory has seen a surge in notably small faceted melee diamonds submitted for identification. In melee sizes less than 0.01 ct, a standard Fourier-transform infrared (FTIR) spectrometer provides a less stable environment for analysis and produces an indistinct spectrum. Diamonds smaller than 0.01 ct prove challenging for other screening devices as well. Meanwhile, there is heightened pressure to identify both loose and mounted melee diamonds in the laboratory quickly and reliably so that each stone can be analyzed. In late 2014, GIA developed a new protocol to use an FTIR microscope to focus on melee diamonds as small as 0.00054 ct (figure 1) to produce high-quality spectra suitable for diamond typing.

Operating the FTIR microscope in reflection mode allows for fine-tuned aligning of the beam within a sample, improving the detail of the infrared spectra. Once a faceted round brilliant melee is stationed on a slide, the microscope beam can be focused either through the pavilion (if the melee is table-down) or through the table at an angle to reflect off an inner pavilion facet (if the melee is resting on the pavilion). Many of the samples were so small that the position of the stone remained unknown until the microscope was focused. Nevertheless, spectral quality was independent of stone position.

All 70 melee examined were natural round brilliants, the smallest a 0.00054 ct colorless sample identified as a type Ia diamond (figure 2). A few screening devices for treatment and synthetics have been introduced for diamonds over 0.01 ct. The FTIR microscope has proved very effective in analyzing melee smaller than this size, either loose or mounted.

Figure 2. This infrared spectrum of the 0.00054 ct diamond in figure 4, obtained using an FTIR microscope, shows the detail that can be captured from very small melee sizes.
The knowledge that GIA can type such small stones and determine their origin, either loose or mounted, apart from being an impressive test of FTIR microscopy, will increase consumer confidence in these remarkable melee diamonds. @chapter:31


Publication Year: - Title: A Sunstone Odyssey, Part 2: The Dust Devil Abstract: The setting sun casts orange rays above basalt boulders at the edge of the Dust Devil mine in southeast Oregon’s high desert. The mine is one of the region’s more important commercial sunstone sources. Photo by Robert Weldon.

INTO THE VALLEY
For the last couple of days we’ve been surrounded by the Ponderosa mine’s towering pines. Today, we’re a hundred miles farther south—and a thousand feet lower—on the road to the Plush sunstone mining area. Our next stop is Don Buford and Terry Clarke’s Dust Devil Mine in the heart of the Rabbit Basin. This is expansive country: forbidding volcanic hills form steep ridges that loom above flat, open valleys dotted with sagebrush. The high desert has its own unique beauty.

View Gallery

	Take a journey to Oregon’s Dust Devil mine. Set in the state’s remote southeast corner, the location produces some fabulous large sunstones, many of which have been carved into award winning gems.
We make the turn off Highway 395’s smooth pavement and head east on Hogback Road’s gravel surface. “Call from there to let us know you are on Hogback Road,” Don’s email said. Everyone has the same cell-phone carrier—there’s no signal, so we can’t oblige.

Don’s email also told us that any car with decent tires would do, and after thirty bumpy miles, we arrive at the mine. As Don assured us: “You can’t miss us, lots of trailers and shakers and conveyors.”

	Terry Clarke and Don Buford have been mining sunstone in the Oregon desert for 21 years. Photo by Robert Weldon.

	This view of the Dust Devil Mine shows Dudeck Ridge in the background. This is likely the local source of the sunstone-bearing lavas. Photo by Robert Weldon.
We ask Don about the history of sunstone in the area known by the miners as the “valley.” He tells us, “Native Americans traded sunstones as far as British Columbia, the Mississippi Delta…and they’ve been found in Viking burial grounds in the northeast.”

Don mentions that Tiffany & Co. of New York mined clear feldspar here as a diamond substitute as recently as the 1950s. Their endeavors led to the gems’ local name: “Plush diamonds.” He adds that they only mined close to the surface and “didn’t get deep enough to get the really nice colored stones.”

MASTERS OF MECHANICAL IMPROVISATION
We ask how Dust Devil got its start, and Don tells us it began as an Explorer Post for the Boy Scouts of America. “We were just looking for something for our scouts to do,” he continues. “We came down here to find some mining claims, and once I started digging, I was very fascinated with the beauty of the stones and how totally different they are from anything else.”

That was the catalyst. Terry and Don started digging for sunstones on weekends and vacations. “We started off with shovels, sixteen-pound sledgehammers, and hand screens, and eventually bought an ancient backhoe.”

	The pit is worked the old-fashioned way. In this image, fee-paying diggers are using screens and shovels to mine the basalt. They only pay for the material they want to keep. Photo by Duncan Pay.
From there on, they obtained any used parts and any scrap steel they could find, and built it into mining machines. “Our first machine was an old school bus that we made into a flatbed.” He adds, “We’ve been out here 21 years, and we’ve seen sunstone go from a stone that nobody had any idea what it was, to now being on the threshold of being an important international stone.”

	The Dust Devil's Origins

	Mine owner Don Buford outlines the mine’s history and explains its origin as a Boy Scout Explorer Post.

THE MINING PROCESS
Don explains that the mine’s location is very favorable. “We’re on the edge of what was a great inland sea, and a river flowed right past our camp, so we have a lot of decomposition of the basalt that holds the sunstone.” This makes the rocks that contain the gems softer and easier to mine.

	This view shows the Dust Devil pit with the mine’s processing plant in the background. Photo by Robert Weldon.
Dust Devil miners use backhoes to work the pit and big loaders to transport the ore to a processing plant. There’s a “grizzly”—mining parlance for a grille that keeps bigger boulders out of the processing plant—and conveyor belts that lead to a shaker and a trommel.

The shaker removes material that’s less than two inches and more than five-sixteenths of an inch in size, Don explains. The trommel washes the concentrate, which then goes to either a one-cubic-yard hopper, where people can pick it off a belt, or to a sophisticated optical sorting machine.

	In this view of the mine’s processing plant, the shaker at top left is feeding ore into the yellow cylindrical trommel. Concentrate can either be directed to the hopper and belt in the foreground or to the optical sorting machine via the conveyor running diagonally to the left. Photo by Duncan Pay.
During our visit, an electrical fault prevented us from documenting the optical sorter. We hope to return at a later date to see the machine in action.

	Mining the Dust Devil

	Don Buford explains the advantages of the mine’s location and how the miners separate the gems from the surrounding ore.

DESERT WISDOM: SHARP-EDGED STONES, TALL SAGEBRUSH, AND BIG ANTHILLS
After a lifetime of working the desert for sunstone, Don turns his miner’s eye to the landscape for clues. The first things he looks for on the surface are stones with sharp edges, which indicate they’ve been recently deposited and there’s probably more underground. He tells us that worn stones with sand-blasted edges might have come from some distance away, or might even have been on the surface for 100,000 years.

Next, he seeks out the tallest sagebrush because it can indicate easier mining conditions. Much of the rock covering the sunstone-bearing basalt is heavy, requiring drilling and blasting, but tall sagebrush—above five or six feet—is a good indication that the plant’s roots are able to reach water, and that means, as Don explains, “the rock is fractured…we can get through it.”

Finally, he advises not to forget the ants. The desert supports vast populations of them. Don indicates that they require a little respect: “These are red ants that have a really nasty bite.”

Around a big ants’ nest, he says, they’ll completely clear a circle ten feet in diameter, then use little pebbles and sunstones to build their mound. They even arrange them close together so when it rains, the water runs off. There’s another benefit: sunstones reflect the light, so in the summer they help regulate the anthill’s heat.

	People aren’t the only ones to mine the desert for gems. Ants collect tiny fragments of feldspar around their nests. Photo by Robert Weldon.
Just like tall sagebrush, a bigger anthill indicates possible penetration into the ground. It’s a strong signal that the rocks underneath are weathered and easier to mine. All these clues tell miners that it’s a good idea to dig adjacent to the anthills.

	Prospecting for Sunstone

	Miner Don Buford shares some of the desert-prospecting wisdom he’s acquired over the years.

ENVIRONMENTAL CONSTRAINTS AND CHALLENGES
Unlike the Ponderosa, which has several natural springs on the property, there’s absolutely no water at the Dust Devil Mine. The Bureau of Land Management (BLM)—the federal agency that administers public lands—prohibits any kind of permanent development in the Rabbit Basin and insists the land be restored to its pre-mining state.

Don explains the location’s challenges: “We’re 21 miles from the nearest electrical power, so we make our own power…We haul our drinking water in from 30 miles away. Our mining water comes from a well that’s six miles away.”

All the water used in mining is extensively recycled. A series of six holding tanks recirculates the 10,000 gallons of water used for washing the concentrate. They allow progressively finer material to separate out before the water is used again. As Don says, “This is the desert, and water is hard to come by…so we don’t use more than we have to.”

When mining ceases, the miners will have to re-contour and replant the area with native species. On his own initiative, Don is planting the native bunch grasses that grew in the valley before extensive sheep farming eradicated them. “We’re putting it back to the way it was before the white man came here and had an effect on the land,” he says.

The desert is hard on men and machines. The gritty attrition of dust and the ringing impact of metal on rock take their toll. You have to be tough and mechanically minded to make it here. “We’re pretty self-sufficient,” he says. “We have a lot of equipment. It’s old equipment and it breaks down a lot, but we have the tools and technology to repair almost anything.”

	When we asked mine employee Mark Shore what it might take to fix this backhoe, he replied “about five sticks” (of dynamite!). Photo by Duncan Pay.
This led us to question the cost of mining in such a challenging environment. With a wry smile, Don admits: “We actually pay every month for the privilege of coming out here and digging these beautiful stones…and getting to hang out with some of the best people in the world.”

	The mine’s harsh, dusty desert environment and its distance from service centers require a fully-equipped machine shop to keep heavy equipment running at Dust Devil. Photo by Robert Weldon.
The act of mining—of recovering beautiful sunstone—outweighs the simple financial rewards for Don and Terry. We get the sense that their best possible legacy for half a lifetime of work would be widespread recognition of Oregon sunstone as a mainstream gem.

Don’s next answer reinforces the fact that he has already done more than anyone to raise this gem’s profile among jewelry designers: “When we got into the very, very large stones in this pit, which at that time were the largest that anyone had ever found, we took our best material to the Tucson International Gem Show.”

He explains how they met with artists that they enjoyed working with and gave them the stones so they could carve or cut them and enter them into prestigious competitions run by the American Gem Trade Association (AGTA). “Over the years,” he continues, “we’ve won sixteen Cutting Edge awards with our stones. We try to be real humble about it, but several of those artists have said that a lot of their fame has come from cutting our stones. Had we not given them those stones, they wouldn’t be where they are today.”

	Challenges of Desert Mining

	Don Buford outlines many of the challenges of operating in a harsh desert environment.

BEAUTIFUL SUNSTONE
For Don, red gems with the glitter of native copper are the most fascinating: “I like the red stones with the copper schiller bars running through them.” Although bicolor gems and stones displaying red to green dichroism might be more rare, he prizes these gems the most. “The reds with the schiller are just very, very dynamic, and there’s nothing else in the world that looks like it.”

	This is what it’s all about: Kilos of gem-quality rough remain after a Dust Devil production run. Photo by Duncan Pay.
Just like John Woodmark of the Ponderosa, Don emphasizes the individual nature of this product. “Every stone is unique, like opal.” He acknowledges that “matching stones up is very difficult.” However, there’s a benefit to this downside, as consumers seek gems that help convey their own individuality: “We’ve always believed that no two women want to look exactly alike.”

	This 101.63-ct. rough sunstone has a deep red core with schiller. It’s likely to be fashioned into a fabulous carving. Photo by Robert Weldon.
Don’s next statement encapsulates his view of Oregon sunstone’s place in the international jewelry marketplace: “Sunstone should be in high-end jewelry stores in all the major cities in this country, and in Europe and Asia—it’s a beautiful, beautiful, brilliant stone.”

We also asked mine employee Mark Shore what brings him to the desert, what drives him to come out here to spend his summers at the mine, what makes him pause to pick a feldspar crystal off the ground. I think my question stings him a little: “Why pick them up? Because they’re beautiful!”

To Mark, a sunstone in your hand is a very special thing: “It’s like holding air or water in your hand…” And his favorite type? “There’s no other stone like a schiller…it dances inside: it’s alive!”

	Why Oregon Sunstone is Unique

	Don Buford describes Oregon sunstone’s unique appeal. He also mentions some care considerations for the gem’s use in jewelry.

THE BEAUTY OF THE DESERT
After just a few days in the high desert, I think we are becoming attuned to its beauty: the clarity of the air, the lure of a red glint of hidden sun in the rock. There’s a lightning storm on our last evening that shocks the sky with blasts of sudden light. We all stay up to watch the hills light up like daytime.

The next morning we leave to visit the last mine on our trip, a distinctly different one where the miners dig into the flank of a small volcanic hill—Sunstone Butte. As we drive off, some of Don’s words ring in my ears: “These stones are mined by hardworking Americans…there’s nothing like it in the world…and Americans should want to buy our stones.”

So, if your car breaks down on Hogback or you get a puncture on Nasty Flat Road, pray you run into Don or Terry. They will fix your flat and set you right.

	The orange glory of the setting sun hovers above a rich high-desert landscape. Photo by Robert Weldon. @chapter:24


Publication Year: 2020 Title: Exceptional Rough and Cut Blue Sapphire from Rock Creek, Montana Abstract: The 17.65 ct “Lucky Sapphire” rough crystal and 3.92 ct oval cut using the custom “Helena” design, both from Rock Creek, Montana. Photo by Robert Weldon/GIA; courtesy of Jeffrey Hapeman.

The Rock Creek sapphire deposit in Montana has been active since the 1890s and is known as the state’s most fruitful deposit (T. Hsu et al., “Rock Creek Montana sapphires: A new age of mining begins,” https://www.gia.edu/
gia-news-research/rock-creek-montana-sapphires-new-age-mining-begins, August 29, 2016). This year in Tucson, Jeffrey Hapeman of Earth’s Treasury showed the authors a very fine untreated blue sapphire rough with a yellow spot in the center, as well as a top-quality faceted light teal blue untreated stone with some yellow zoning (see above). Since 2014, Mr. Hapeman has been focusing on Rock Creek material in these nontraditional lighter blues to greens. They have proven to be very popular, as several AGTA vendors this year reported strong demand for these colors, not only in Montana sapphire but from other sources as well. When it comes to unheated material, only about 5% of the rough from Rock Creek is cut without treatment, and most of these are either fancy pinks, yellows, or lighter blues. In the past year Mr. Hapeman has seen a shift in demand to parti-colored and green sapphires, particularly deep bluish green. @chapter:20


Publication Year: - Title: Students Eager to Learn New Jewelry Design and Technology Techniques Abstract: Students Amanda Street, background, and Tyler Abe, use dual screens to simultaneously perform CAD rendering (left) and modeling (right).

                      It can be challenging to learn to design in three dimensions when you’ve only previously worked in two, but that’s exactly what students in the computer-aided design and computer-aided manufacturing (CAD/CAM) component of GIA’s newly updated Jewelry Design & Technology (JDT) course  do.

“It’s trying to figure out how to retrain your brain to think in three dimensions,” said Hannah Becker, who started the course a month ago and has experience working in two-dimension as a photography and art history major in college. “We learn the basics – like making a square into a cube – and as we learn different tools and how they move, it’s been really intriguing to wrap your brain around.”

“There’s a lot of problem solving, so it does seem like a game sometimes. When I look at a form, I think ‘how would I create this shape, what type of movement would I have to envision to make this into an object.’ It’s kind of like a fun puzzle to solve for me,” she said.

Becker, who graduated from Bard College in Annandale-on-Hudson, New York with a degree in art history, wrote her thesis on glitter in contemporary art and was looking for a medium to channel her passion for sparkly things into a tangible career. She discovered the “concept of connoisseurship within the field of sparkly things” when she helped her brother shop for an engagement ring and learned about GIA.

She said she is enjoying the work in the JDT class because she is using both sides of her brain. “It’s like math, there is a right and a wrong answer, but we also have the creativity of it being design,” she said.

And that is the point of the six-month JDT course, said Mark Mann, GIA’s director of Global Jewelry Manufacturing Arts. Students learn all of the hands-on, practical tools they need to know to bring their artistic visions to life.

“The course not only offers CAD modeling techniques, they’re also learning jewelry design, engineering and manufacturing essentials. This jewelry manufacturing overview will assist them in successfully building functional products,” he said.

The redesigned jewelry arts classrooms in Carlsbad are outfitted with high-tech manufacturing and learning tools for efficient, visual and interactive education geared to today’s jewelry industry, he said.

“By incorporating the latest technologies, like rapid prototyping of designs using wax mills and 3-D printers, we prepare students for how the industry works today, which saves future employers time and money,” Mann said. “Graduates will enter the jewelry industry with up-to-date skills and unsurpassed learning experience.”

	Instructor Michael Magee, left, teaches students how to use the Digital Wax 028 Rapid Prototype machine. Students, from left, are Tyler Abe, Amanda Street and Hannah Becker.
That includes the latest adult learning techniques that incorporate project-based, self-directed, experiential and action-oriented learning criteria. With these learning features in mind, each lesson contains a mix of tutorials on CAD design and modeling techniques, small group assignments, related development of personal design idea guidance, as well as footage from actual production facilities making products. Instructors lead them through the lessons and provide one-on-one help when needed.

“We mix up the content to keep it more interesting, but it’s all related,” Mann said. The lessons build upon one another and include mandatory and practice homework. Students need to keep pace in developing their skills or they will fall behind, he said.

Tyler Abe, a former engineering student from Seattle, said the video tutorials are easier to follow than the print-based ones he used in his engineering classes.

“I took a CAD course for engineering and it took me about three months to learn probably what I learned in three weeks here,” he said. “Seeing how far we’ve come in one month and knowing that we have another five months to go, I have a feeling we’re going to be very proficient at this by the end of the class.”

Product spec sheets are a very important element of the class, Abe said, because that’s what the real world works with.

“I find it really enjoyable when they give us a spec sheet and ask us to create it,” Becker said. “They talk about CAD-think – training your brain so that when you see an object, you break it down into the steps: what is the start and what is the finish and at what point in the process you should be focusing on specific details.”

Amanda Street, from Fallbrook, California was searching for a career that would give her an opportunity to fulfill her art and design aspirations when she decided to attend GIA. The CAD/CAM lessons are fun because they are “like playing a video game,” she said, but “they are really preparing us” to work in the real world.

Becker couldn’t agree more.

“I feel confident that when I go to get a job, I will be really competent and proficient at doing things in a work-type environment,” Becker said. “It makes me feel like I will be able to create something that someone asks me to and I won’t have to worry about it being off. I’d like to know that if I’m asked to make something that will be cast in platinum that I’m not going to mess it up.”

The next JDT course will be offered Sept. 26 in Carlsbad and there are plans to make this program available at the Institute’s New York campus in 2014. Students can apply now.

	Instructor Steve Roehl, right, reviews a prototype model of a ring with student Scott Sokolowski. @chapter:36


Publication Year: - Title: Jade History and Lore Abstract: This jadeite "Peiyao" (Chinese Fu dog) represent mythological creatures that guard and protect celestial palaces and entrances. - Gift of Sophie Leu

                      Jade has been cherished for thousands of years. It’s considered pure and enduring enough to inspire the wearer’s highest spiritual aspirations, yet sensuous and luxurious enough to satisfy down-to-earth cravings. Asian consumers have never lost their fascination for jade, and today, non-Asian buyers are drawn to jade as never before. All are attracted by its rich heritage as much as by its beauty, durability, and rarity.

Nephrite jade has its cultural roots in the smoke-dimmed caves and huts that sheltered prehistoric humans. In China, Europe, and elsewhere around the world, Stone Age workers shaped this toughest of minerals into weapons, tools, ornaments, and ritual objects. Their carvings invoked the powers of heaven and earth and mystic forces of life and death.

	Nephrite carvings have been popular in China for centuries. Photo courtesy China Gems.
The ancient relationship between this gemstone and humanity persisted into modern times among native societies in New Zealand and parts of North America. In China it evolved into an artistic tradition that has flourished for more than 3,000 years.

In Central America, the Mayans and the Aztecs prized jadeite jade. They used it for medicinal purposes as well as for jewelry, ornaments, and religious artifacts. The name jade comes from the Spanish expression piedra de ijada—literally “stone of the pain in the side.” Early Spanish explorers named it after they saw natives holding pieces of the stone to their sides to cure or relieve various aches and pains. Jadeite also symbolizes prosperity, success, and good luck.

It was in China—where the gem-carving tradition was already thousands of years old—that jadeite reached its peak as an important artistic medium. The first jadeite reached China from Burma (now known as Myanmar) in the late 1700s, and late eighteenth and early nineteenth century carvers created masterpieces that are still unsurpassed in concept, design, and technical execution.

The Chinese associate jade with clarity of mind and purity of spirit. Some of the ancient symbolic motifs still used in modern jade carvings (both nephrite and jadeite) include:

		Bat—happiness

		Butterfly—long life

		Dragon—power, prosperity, and goodness

		Peach—immortality

		Bi (flat circular disk with a hole in the center) - heaven

	This butterfly pin has wings carved from fine lavender jadeite. The butterfly symbolizes long life. - Courtesy Mason-Kay Fine Jade Jewelry

	The simple elegance of the disk-shaped Chinese eternity symbol, or bi, carries great spiritual significance for many Asians. - Courtesy Mason-Kay Fine Jade Jewelry @chapter:25


Publication Year: - Title: Montana Yogo Sapphires’ Unique Gemology Abstract: This suite of rough and cut Yogo sapphires shows the wide range of blue to violet or purple hues and light to dark saturation combinations that can be found in Yogo sapphires. The largest faceted stone is a 1.44 ct cushion cut. Courtesy of Bill Vance. Photo by Kevin Schumacher

Despite its Atlantic-to-Pacific land mass, the United States never has been known as a major source for gemstones. The one exception has been sapphire, though the story of Montana sapphires always has been obscured by more exotic locations.
Montana has been an important source of blue sapphire off and on since the 1890s and have unique gemological properties that distinguish them from those mined in other locations around the world, including Kashmir, Myanmar, Sri Lanka and Australia. GIA researchers Nathan D. Renfro, Aaron C. Palke, along with Richard B. Berg of the Montana Bureau of Mines, conducted an extensive analysis of gems from the Yogo Gulch deposit, reporting their findings in Gems & Gemology’s Summer 2018 issue.

The flat tabular shape of the Yogo rough often dictates the production of stones under 1 ct in weight. Photo by Robison McMurtry.
Yogo sapphires’ chief trait is that many of them have an attractive violet to blue color coming out of the ground and are generally not heat treated – the gem-quality stones rarely, if ever, respond to treatments. In addition, the color is generally evenly spread throughout the stones, so they lack the zoning that can be common in sapphires from other locales. Unfortunately, nearly all of the rough crystals are flat, tabular pieces that can only be cut into small gems. Thus, carat-plus sapphires from this source are quite rare.
Deeper gemological examination found that Yogo stones are unique in other ways as well. Most blue sapphires contain tiny needle-like or “silk” rutile inclusions. In the case of the classic Kashmir stones, for example, the clusters of near microscopic rutile impart a velvety glow to the gem, making them highly prized, with price premiums to match, for more than a century. This silk also can be a distracting clarity characteristic of some sapphires at times and heat treatment is relied upon to improve their clarity and color. On the other hand, Yogo sapphires rarely contain fine, needle-like rutile silk which was found in only one of the samples examined.

Rutile crystals can be seen as elongated rods with a dark brownish green color, left, and as black opaque rounded crystals with tension cracks and healed fringes that result from the igneous growth environment, right, and not from heat treatment. Photomicrographs by Nathan Renfro
Inclusions are often the most tell-tale signatures of a gem’s origin and Yogo’s primary signs are stress halos that surround very small pieces of other minerals trapped inside the still-forming sapphire. The halos (also called decrepitation halos) were formed when the mineral inclusions expanded inside the sapphire during its formation and caused tiny stress fractures. Other common, but distinctive inclusions are negative crystals – very small hollow areas filled with other materials.
Even deeper examination found that Yogo sapphires have a distinct trace element signatures with specific values of manganese, chromium, titanium, iron and gallium that are different from other sapphires.
While Yogo sapphires, and most other sapphires emanating from Montana, have an attractive natural blue color that commands premium prices, their small sizes and the complexities of working the deposits made it economically difficult to mine them.

This suite contains more than 36 carats of Yogo sapphires. Courtesy of Edward Boehm. Photo by Robert Weldon/GIA
The first Yogo source was discovered in 1895 and by the turn of the century, production averaged 400,000 carats a year. About 25% were gem quality and the remainder industrial goods used in watch movements and abrasives. This mine, sometimes referred to as the English Mine, operated until 1929. In 1910, it yielded the largest sapphire ever found in that locale, a 19 ct rough that was cut into four gems, the largest 8.5 cts.
The mine site is located within a long dike (a geological formation of volcanic rock layered above older, pre-existing rock) that held other sapphire deposits. Three other mines went into operation but, by the late 1920s, competition from synthetic sapphires for watch movements and abrasives, coupled with a disastrous flood and declining yields, made mining unprofitable.
The area remained abandoned for nearly 30 years before a group of investors renewed mining activities in 1956, but were unsuccessful. Several other failed attempts to revive mining at Yogo Gulch were made until 1980, when a mining engineer named Harry Bullock acquired the mining operations for $6 million and set out on a well-publicized effort to mine and market “Royal American Sapphires” under the corporate name Intergem. After some initial success, competition from inexpensive heat-treated Sri Lankan sapphires, mounting debts and increased mining costs sank the venture in 1985.

With activities resuming at Yogo Gulch, the industry may see more contemporary jewelry designs using the deposit’s sapphires. The suite shown here incorporates the blue material that made Yogo famous, along with the purple stones that remain a rarity. The center stone of the ring weighs 1.36 ct. Courtesy of Bill Vance. Photo by Kevin Schumacher
That year, prospectors found a new deposit in the southwestern tip of the dike. They called it the Vortex Mine and produced about 45,000 carats of cuttable rough a year, but closed in 2004. The following year, a miner named Mike Roberts took a part ownership of Vortex and successfully mined it on a small scale until he was killed in a mine site accident in 2012.
New owners are trying yet again to resume mining the Yogo Gulch and have been working on making necessary improvements to bring the mine back into production.
This research project, Renfo and Palke noted, “was a few years in the making.” One motivating factor for the study was the demand for Yogo origin, instead of the more general USA (Montana) notation on GIA lab reports.
A second factor, Renfro said, was that there was a “hole in the literature. Previous publications generally focused only on the geology (of the Yogo area), but there was no thorough gemological characterization of the material.”
And a third motivation was, “I just like Yogo sapphires,” he said.
Nathan Renfro completed his undergraduate studies in geology in 2006 and enrolled in GIA’s resident Graduate Gemologist (GG) program as a recipient of the William Goldberg Diamond Corporation scholarship. Renfro also completed his FGA in 2014. After finishing the GG program, he was hired by the GIA laboratory as a diamond grader and soon transferred to the Gem Identification department in 2008. Since then, Renfro has authored or co-authored more than 100 gemological articles and lectured to several gem and mineral groups throughout the U.S. His primary areas of gemological interest are inclusion identification and photomicrography, gemstone cutting and defect chemistry of corundum. Renfro is manager of the Gem Identification department and also is a microscopist in the Inclusion Research department. He is also the editor of the “Microworld” column in Gems & Gemology and a member of the editorial review board.
Dr. Aaron Palke started his career in gemology as a postdoctoral research associate at GIA after earning his Ph.D. in Geology from Stanford University. During this time, Palke investigated the geological history of rubies and sapphires by studying minute inclusions in these precious gems. A senior research scientist at GIA, he helps lead colored stone research efforts in order to provide more reliable country of origin determinations and treatment identification for rubies, sapphire, emeralds and other colored stones. See Palke's profiles on ResearchGate and Google Scholar. @chapter:7


Publication Year: 2016 Title: Screening of HPHT Synthetic Melee With Natural Diamonds Abstract: Figure 1. This parcel of 3,005 melee diamonds with a total weight of 70.56 carats was submitted for analysis. Photo by Ivana Petriska Balov.

Significant amounts of melee-size synthetic diamonds produced by both HPHT and CVD technologies are manufactured for the jewelry industry. The “salting” of natural diamond melee parcels with HPHT-grown synthetic melee is seen more frequently in the trade today. This presents a threat to the integrity of diamond dealers and manufacturers who might unknowingly sell or use synthetic diamonds and represent them as natural. In response, GIA has introduced a melee analysis and screening service aimed at helping the trade combat this problem. The screening is rapid and relatively inexpensive. This service can screen large quantities of diamond melee and separate natural diamond from synthetic material (both HPHT and CVD grown), natural HPHT-processed diamond, and diamond simulants such as cubic zirconia or moissanite. In addition, a color grade within the D–Z range can be assigned to each diamond.

In August 2016, a group of 3,005 melee with a total weight of 70.56 carats (figure 1) was submitted to GIA’s New York lab for screening service. Initial testing using our fully automatic screening device, which is based on spectroscopic methods, passed 2,969 (98.7%) of them as natural diamond. Of the remaining 36, 12 were subsequently identified as natural material by methods including photoluminescence (PL) spectroscopy, and only 24 were referred for further testing to confirm their identity as natural, treated, or synthetic diamond.

Additional testing with Fourier-transform infrared (FTIR) absorption spectroscopy, Raman PL spectroscopy, and fluorescence imaging techniques identified 21 of these 24 melee as natural diamond. This analysis also confirmed that three (0.1%) of the melee in the parcel were HPHT-grown synthetic diamonds (figure 2).

Figure 2. From an initial screening of 3,005 melee diamonds, 24 specimens were
referred for further testing. Of these, three were HPHT-grown synthetic diamonds. Photo
by Jian Xin “Jae” Liao.
This highlights the practice of “salting” parcels of natural diamond melee with a small percentage of synthetic diamond melee, and the importance of advanced testing to identify them. @chapter:15


Publication Year: - Title: Top Gems Continue to Set Records at 2015 Auctions Abstract: The 16.08 ct. Fancy Vivid pink diamond sold for $28.5 million to the same buyer who bought the record-breaking Blue Moon Josephine diamond. Photo courtesy Christie’s

                      The major auction houses had another successful year with fine jewelry, helped immensely by record-setting bids from a number of private buyers.

Christie’s and Sotheby’s, who dominate the auction market worldwide, recorded an estimated $1.2 billion in gem and jewelry sales between them for the year. Other auction houses that sold very important gems, including Bonham’s of London and Tiancheng in Hong Kong, added $70 to $80 million to the total.

This total is down slightly from last year, said Francois Curiel, chairman of Christie's Asia-Pacific. “The market showed great interest in rare, top-quality stones, with very high prices,” he said. “The middle market pieces showed a lot more resistance.”

	The $48 million Blue Moon Josephine, a 12.08 ct. Fancy Vivid blue, is the most expensive gemstone ever sold at auction. Its $4 million per carat price exceeded the previous record by $1 million. Photo courtesy Sotheby’s

Several gems made worldwide headlines this fall:

		A 12.03 carat (ct.) Fancy Vivid blue diamond sold at Sotheby’s Geneva Nov. 19 for $48 million, making it the most expensive gemstone ever sold at auction − and the most expensive per carat: $4 million per carat. The buyer was a Hong Kong businessman named Joseph Lau who named the diamond Blue Moon of Josephine in his daughter’s honor. The same buyer purchased a 16.08 ct. Fancy Vivid pink diamond at Christie’s Geneva the day before (Nov. 18). Both diamonds were graded by GIA.

		At the same Christie’s Nov. 18 sale, a major dealer bought a 50.48 ct. pear-shaped D Fl diamond, graded by GIA, for $7.84 million or $155,264 per carat.

		In addition, a private buyer paid $18 million for the 15.04 ct. Burmese ruby that Christie’s named the Crimson Flame. The gem, which sold in Hong Kong on Dec. 1 to a private buyer, was the highest price ever paid per carat at auction for a ruby.

		A private buyer at Sotheby’s Hong Kong October sale broke the newly set per-carat price for a Kashmir sapphire by paying $242,145 per carat for a 27.68 ct. gem. Another buyer at this sale paid a record $5.2 million for a natural gray pearl necklace, called the Chowdray Pearls.

	The 15.04 ct. Crimson Flame, an exceptionally rare Burmese pigeon’s blood ruby, is the highest price ever paid per carat at auction for a ruby: $1.2 million per carat. Photo courtesy of Christie’s

The year at Sotheby’s New York closed with a $52 million sale that included a 25.87 ct. sugar loaf cut Kashmir sapphire that drew a winning bid of $5.1 million. The Kashmir sapphire easily surpassed the highlight of the sale, a diamond necklace that Van Cleef & Arpels fashioned for Queen Nazli of Egypt in the 1930s, which sold for $4.3 million.

Christie’s finished the year with a $4.3 million bid for the 31.34 ct. D VVS2 Victory Diamond once owned by heiress Florence Gould. The diamond was scheduled to be sold last year with a $5 to $8 million pre-sale estimate, but failed to meet its reserve. At the same sale, a 43.79 ct. D VS1 cushion-shaped Type IIa diamond drew a $4 million hammer price, and a 103.66 ct. diamond graded L VS2 by GIA drew a bid of $3.75 million. A 23.98 ct. Burmese sapphire sold for $1.5 million, nearly double its pre-sale estimate, but the 12.52 ct. Matice Kashmir sapphire did not meet its reserve.

	This four-strand colored natural pearl necklace set a record bid of $5.2 million from an Asian private buyer at Christie’s April 14 auction in New York. Photo courtesy of Christie’s

At Bonham’s Dec. 5 London sale, a pair of Kashmir sapphire earrings (7.92 ct. and 7.96 ct.), nearly doubled their pre-sale estimate, selling for $2.3 million. The 19th century earrings were once owned by an unnamed European princess.

Christie’s closed the spring auction season with a $118 million sale in Hong Kong, the highest total achieved for a sale in Asia. Nearly 90% of the lots offered were sold and prices, while not quite record breaking, were very strong. The top lot was a 120 ct. Burmese ruby and diamond necklace by Etcetera that sold to a private Asian buyer for $13 million.

	Van Cleef & Arpels fashioned this diamond necklace for Queen Nazli of Egypt in the 1930s. Set with more than 600 round and baguette diamonds weighing a total of approximately 217 carats, it sold for $4.3 million. Photo courtesy of Sotheby’s

On May 13 in Geneva, Sotheby’s sold the first ruby to break the $1 million per carat record. The 25.59 ct. Sunrise ruby doubled its pre-sale estimate to achieve a final price of $30.3 million, the highest price ever paid for a ruby at auction. This auction resulted in the highest total ever for a jewelry auction: $160.91 million, nearly $20 million above the previous record. The auction catalog noted the ruby was Burmese, with no evidence of treatment.

The sale also featured an 8.72 ct. GIA-graded Fancy Vivid pink diamond that reportedly was linked to Princess Mathilde Bonaparte, the niece of Napoleon Bonaparte. The cushion cut diamond sold for $15.9 million, or $1.82 million per carat. The diamond had been stored in a bank vault since the end of World War II.

	The Victory Diamond, a D VVS2 emerald-cut diamond ring of 31.34 carats, sold for $4.3 million in late 2015. Photo courtesy of Christie’s

In Hong Kong, Tiancheng International reported its most successful jewelry auction ever on June 14. The sale totaled U.S. $38 million, and included a 25.72 ct. D VS2 heart-shaped diamond that sold for $3.18 million. The diamond was cut from a 67.45 ct. piece of rough.

The market for top gems at auction offered a bright spot in an otherwise difficult year for the industry. More stones such as these will liked come to market in 2016, including some of the major diamonds mined during the previous year. @chapter:30


Publication Year: 2022 Title: HPHT-Processed Natural Type Ia Diamond Abstract: Figure 1. This 5.17 ct Fancy Deep yellow-orange HPHT-treated diamond was resubmitted to the New York laboratory. Photo by Towfiq Ahmed.
There are two types of high-pressure, high-temperature processes related to diamond: HPHT treatment and HPHT diamond growth. HPHT laboratory-grown diamonds were developed in the mid-1950s, with the first gem-quality production in the early 1970s and extensive production beginning in the 1990s.
HPHT treatment to change the color of natural diamonds was discovered as a byproduct of annealing natural diamond anvils. The General Electric Company (GE) and Lazare Kaplan International marketed the first commercial HPHT-treated color diamonds in March 1999 (K. Schmetzer, “Clues to the process used by General Electric to enhance the GE POL diamonds,” Winter 1999 G&G, pp. 186–190). The same machines, such as a hydraulic press that produces extremely high pressure and temperature environments, are also used to treat both mined and laboratory-grown diamonds. HPHT treatment can change the color of diamonds or make them colorless.

Figure 2. Table-down images showing the diamond before HPHT treatment (left) and after (right).

Figure 3. This natural anhedral crystal was formed during diamond growth and acquired a graphitized halo after HPHT treatment. Photomicrograph by Sally Ruan; field of view approximately 1.26 mm.
A natural 5.20 ct type Ia SI2 Fancy Dark yellowish brown diamond with natural anhedral crystal inclusions was submitted to the New York laboratory for grading services and returned. After being treated, it was resubmitted as a 5.17 ct type Ia SI2 Fancy Deep yellow-orange diamond (figure 1), with the disclosure that it had been HPHT processed. After analysis, the diamond was confirmed to have been treated using an HPHT process that changed the color from a dark yellowish brown to a deep yellow-orange (figure 2). After the HPHT process, each of the natural anhedral crystal inclusions developed a graphitized halo (figure 3). In the natural diamond, the visible/near-infrared (Vis-NIR) absorption spectrum showed a slight 550 nm band—a feature that may impart a pinkish color component depending on its absorbance and other features present within the diamond. After HPHT treatment, there is instead an increase in absorption from ~500 nm toward the lower wavelengths; this absorption rise is due to the creation of single, isolated nitrogen (figure 4).

Figure 4. Vis-NIR spectra show the untreated natural diamond with the 550 nm band (orange line). After HPHT treatment (blue line), the 550 nm band is not apparent. Instead, there is an increase in absorption from 500 nm toward the lower wavelengths (higher energy). Spectra are offset for clarity.

Figure 5. The B region of the mid-infrared spectrum shows a new isolated nitrogen peak at 1344 cm–1 and a diminished ~1363 cm–1 platelet peak after HPHT processing (orange line). The A region of the mid-infrared shows that the natural amber center at ~4165 cm–1 (shown in orange) was destroyed after HPHT processing. The spectra are baseline corrected.
As expected (I.M. Reinitz et al., “Identification of HPHT-treated yellow to green diamonds,” Summer 2000 G&G, pp. 128–137), FTIR data from after the HPHT treatment showed that a peak associated with isolated nitrogen at 1344 cm–1 was introduced, the ~1363 cm–1 platelet peak was diminished, and the natural amber center at ~4165 cm–1 was destroyed (figure 5). Since the spectroscopic data changed after treatment, crystal inclusions plotted on the original grading diagram for this diamond confirmed it was the same stone. The 550 nm band in the Vis-NIR absorption spectrum related to a pink or brown diamond is stable at lower temperatures of HPHT treatment. Since the 550 nm band was not detected after the process, we believe this diamond was treated at the higher end of the HPHT regime or for a prolonged duration that required repolishing, which caused it to lose three points of carat weight.
While there are many different treatments that can be performed on diamonds, HPHT treatments are permanent and require a stable and controlled environment. In this stone, the treatment resulted in some of the nitrogen aggregates being split apart into single, isolated nitrogen that introduced new color centers and altered the color of the treated stone. The treatment also graphitized inclusions; however, this change was not sufficient to lower the clarity grade. As technology advances, HPHT treatments are becoming more common for both natural and laboratory-grown diamonds. @chapter:15


Publication Year: - Title: Fancy Black NPD Synthetic Diamond Abstract: Figure 1. This 0.9 ct marquise proved to be a synthetic nano-polycrystalline diamond (NPD), the first one detected by a gemological laboratory. Photo by Jian Xin (Jae) Liao/GIA.

                      As reported previously in Gems & Gemology, nano-polycrystalline diamond (NPD) growth technology is one of the most significant new developments in diamond synthesis (see E.A. Skalwold, “Nano-polycrystalline diamond sphere: A gemologist’s perspective,” Summer 2012 G&G, pp. 128–131). The sphere’s material is completely transparent and comparable to natural diamond, while tougher than natural diamond or previous synthetic diamonds. NPD could pose a challenge to the natural diamond industry once these goods, particularly higher-quality transparent samples, enter the consumer market (E.A. Skalwold et al., "Characterization of a synthetic nano-polycrystalline diamond gemstone," Fall 2012 G&G, pp.188–192).

Recently, the New York laboratory tested a small, black marquise-cut stone for identification and color origin. At first glance, the 0.9 ct translucent specimen (figure 1) resembled a typical black diamond submitted to the lab for identification and color origin; one must be careful to separate such stones from synthetic moissanite. This marquise, however, revealed unusual properties strikingly similar to those of the NPD synthetic diamonds reported on by Skalwold, as well as other previously tested samples. These previously studied specimens were transparent with a yellow to brown range of color.

	Figure 2. Micrograph images of the heavily included synthetic diamond showed an abundance of graphite inclusions and a murky yellowish matrix. Photomicrographs by Paul Johnson/GIA, fields of view (clockwise): 1.5 mm, 3.1 mm, 1.5 mm, and 4.1 mm.
Unlike natural diamond, the stone in question was heavily included with graphite crystals. The matrix hosting the inclusions had a murky yellowish color (figure 2). Using diffuse reflectance, we obtained a mid-infrared absorbance spectrum strikingly similar to that of the NPD synthetic diamonds reported in the aforementioned article. We observed the diagnostic diamond absorption peaks at approximately 2000 cm–1 and absorption in the one-phonon region, possibly due to nitrogen impurity. Peaks at approximately 3727 and 3611 cm–1 were also observed, as in some previously tested NPD samples (figure 3). Raman spectroscopy is a common and useful technique in identifying a gem diamond. Due to the nano-sizes of the crystals that compose the aggregated sample, a Raman shift is usually not detectable in NPD using visible-light laser excitations. The same feature was observed in this specimen.

	Figure 3. The mid-infrared spectrum of the 0.9 ct black marquise-cut synthetic NPD (in red) displayed peaks at approximately 3727 and 3611 cm–1, which have been observed in some other NPD samples. The mid-IR spectrum in 2012 by Skalwold et al. (in blue) is provided for comparison.
Further analysis using the DiamondView instrument revealed a fluorescence pattern and structure that was, again, very similar to earlier NPD samples (figure 4). Raman analysis showed a broad band at approximately 1350 cm–1 and a weak band at about 1580 cm–1; these are assigned as D- and G-bands, respectively (S. Odake et al., “Pulsed laser processing of nano-polycrystalline diamond: A comparative study with single crystal diamond,” Diamond and Related Materials, 2009, Vol. 18, pp. 877–880). Odake reported the two bands in NPD samples grown from high-purity graphite at a temperature of 2600K and a pressure of 15 GPa; both are caused by nanocrystalline graphite or amorphous carbon. Unlike Odake’s samples, which showed G- and D-bands of equal intensity, ours showed a strong D-band with a weak G-band. We measured Raman spectra at many different locations, but did not observe the diamond Raman band at 1332 cm–1, an absence Odake also reported. This suggests the presence of sp2-bonded carbons instead of sp3-bonded carbons.

	Figure 4. DiamondView images of the synthetic NPD exhibited a distinct fluorescence pattern. Images by Paul Johnson/GIA.
Testing and observations revealed the diamond to be an NPD synthetic diamond, the first detected by a gemological laboratory. @chapter:11


Publication Year: 2015 Title: GSA 2015 Annual Meeting Abstract: The Geological Society of America’s annual meeting, held in Baltimore November 1–4, attracted more than 6,000 geoscientists from around the world. Two technical sessions, one oral and one poster, were devoted to the gemological field. The poster session’s flexible presentation time and format, along with the wide range of topics covered (including diamond defect formation and low-pressure, high-temperature [LPHT] treatment of type Ia diamonds), allowed for dynamic discussion between exhibitors and viewers.

George Harlow (American Museum of Natural History, New York) opened the oral session by discussing how gemological studies provide insight into the geological developments of Earth. Wuyi Wang (GIA) presented the discovery and distribution of [Si-V]– defects in HPHT synthetic diamonds. This study challenged the widely accepted theory that [Si-V]– defects only occur in CVD synthetic diamonds, while also showcasing photoluminescence mapping as a powerful research technique.

Laurent E. Cartier (Swiss Gemmological Institute, Basel) applied DNA analysis to the origin determination of organic gems, and this presentation focused on pearls. For the first time, gemologists can conclusively identify the mollusk species of a pearl; Dr. Cartier’s team is exploring similar possibilities with coral and ivory.

Karen Smit (GIA) studied the Re-Os isotope of sulfide inclusions in type Ib diamond from West Africa. The isotopic study was used to explain the assembly of the Gondwana supercontinent. Steven Shirey (Carnegie Institution of Washington) presented his Re-Os geochronology study on a sulfide inclusion within a superdeep diamond from Brazil. The age of this inclusion indicated crystal recycling facilitated by mental convection beneath. Both studies demonstrated the vital role gem materials play in earth science research.

	Gemological studies of famous stones and historical jewelry pieces were also represented. Alan Hart (Natural History Museum, London) studied the creation of the Mogul cut. Using the Koh-i-Noor diamond as a case study, Mr. Hart found that differential hardness was the key factor that brought about the Mogul cut with the primitive cutting tools available in the mid-19th century. Raquel Alonso-Perez (Harvard University) used both spectroscopic and trace-element analysis to study the tourmalines mounted in the Hamlin Necklace, a piece of 19th-century North American jewelry.

	Inclusion study is one of the pillars of modern gemology. John Koivula (GIA) pointed out the possibility of misidentifying synthetic corundum as heat-treated natural material. Experimental studies have demonstrated that heat-fused cracks generated in both pulled and flame-fusion synthetic corundum appear virtually identical to the features associated with so-called flux-healed natural stones. Aaron Palke, also of GIA, hypothesized that unusual glassy melt inclusions found in sapphires from southwestern Montana are crystallized as peritectic minerals formed during high-grade metamorphism, generating silica-rich melt and an alumina-rich restite. Future research on this topic may shed light on the source and transportation of Montana sapphires.

	Phenomenal gems were also explored. Keal Byrne (Smithsonian Institution) investigated the luminescence of “chameleon” diamonds, which show an intriguing color-change response to temperature and/or light. Xiayang Lin (Pennsylvania State University) discovered the microscopic surface feature that causes iridescence in natural quartz crystals from India.

	Researchers also spoke about American gem deposits. Michael Wise (Smithsonian Institution) discussed his work on the hydrothermal emerald and hiddenite mined in the Hiddenite area of North Carolina, while Yury I. Klyukin (Virginia Polytechnic Institute and State University) investigated the fluid evolution of the emerald deposit at the North American Emerald Mine, also in the Hiddenite region. William B. “Skip” Simmons (Maine Mineral and Gem Museum) shared the recent discovery of gem-quality pollucite in Mt. Mica pegmatite.

	The details of all oral presentations from the GSA meeting can be found at https://gsa.confex.
	com/gsa/2015AM/webprogram/Session37638.html. GSA’s 2016 annual meeting will be held September 25–26 in Denver. @chapter:29


Publication Year: 2003 Title: Summer 2003 G&G Book Reviews Abstract: “Krystallos—Brazil: Gem-Crystals in Design”
By Sonia Fonseca and Norman M. Rodi, Eds., 178 pp., illus., publ. by Terra das Artes Editora, São Paolo, Brazil, 2002. US$120.00

“The Fabergé Menagerie”
Organized by the Walters Art Museum, Baltimore, MD, in cooperation with the Fabergé Arts Foundation, Washington, DC, 192 pp., illus., publ. by Philip Wilson Publishers, London, 2003. US$25.00

“The Great Book of Amber”
By Elz.bieta Mierzwin ́ ska, photos by Marek Zak, 160 pp., distrib. in the U.S., Canada, and Australia by Amber#1, San Francisco, CA, 2002. US$45.00

“The Rings Book”
By Jinks McGrath, 128 pp., illus., publ. by Krause Publications, Iola, WI, 2003. US$24.95

“The Ultimate Orient: Philippine South Sea Pearls”
Photography by Scott Tuason, 175 pp., publ. by Jewelmer International Corp., Makati City, Philippines, 2001, US$65.00

To view the full section, download the PDF above. @chapter:21


Publication Year: - Title: Slow Diamond Market Puts Miners Under Pressure Abstract: Rough diamonds still remain too costly to manufacture profitably, say dealers, putting pressure on the major producers. Photo by Russell Shor.

                      The soft conditions in the world diamond industry are making their way into miners’ bottom line. De Beers’ sales for the first half of the year were down 26% as clients deferred and outright refused a significant percentage of sight allocations.

This continued for the July 13-17 sight, originally planned at $600 million then reduced to about $450 million. Most clients refused or deferred unprofitable goods, bringing the total to less than $300 million.

De Beers held the line on prices in July.

While De Beers is nowhere near the monopoly it was 15 years ago, it still commands a major market share of the one carat-plus market. The company has reduced sales reluctantly – mainly because buyers have refused or deferred allocations – and has not significantly lowered prices.

Alrosa, the largest diamond producer by volume (second by value), also held the line on prices and allowed clients to defer up to 30% of their allocations. It noted that its first-half rough sales were also 26% below last year’s levels with prices down about 7%.

Tender auction sales by other producers have been running 15-25% below last year’s levels, though rough prices have receded only a few percentage points.

Mega diamonds remain the exception. Lucara Diamond Corp., which operates the Karowe Mine in Botswana, reported very strong prices at its July tender, largely from a 341.9 carat (ct.) Type IIa diamond that brought a winning bid of $20.55 million and a 269.7 ct. diamond that sold for $16.54 million. Both exceeded $60,000 per carat.

Further down the diamond pipeline, two large manufacturing operations closed in Surat, leaving obligations of more than $140 million. As reported earlier, manufacturing volumes have decreased by about one-third, causing a number of contract cutting shops in India and China to close.

While U.S. diamond and jewelry sales have edged into positive territory for the first time this year (May was up by 0.5% from 2014), China’s economic situation continues to deteriorate, which is reflected in its retail jewelry sales.

Chow Tai Fook, China’s largest retail jewelry operation, reported a 15% drop in same store sales for the quarter that ended June 30, the fourth such double-digit decline in a row. Most of the problem is centered in Hong Kong and Macau where tourist traffic is considerably off. Mainland China sales, however, are also lower – with “Gem-set” pieces running 4% down.

Another large Hong Kong based chain, Luc Fook, recorded a 20% drop in same store sales for the quarter.

Indeed, China’s diminishing economic growth is causing considerable volatility in prices and reduced demand for many commodities, causing some mining companies – which two or three years ago could not keep up with demand – to retool their operations. Prices for copper, coal, iron ore, platinum and rare earths used in manufacturing electronics have fallen sharply this year.

In Japan, the country’s ageing population, coupled with low economic growth and stagnating economy, has resulted in a major diamond sell-off. The government noted that polished diamond exports – mainly goods sold by consumers – increased 77% during the first four months of this year. The government estimates the market for “recycled gold and diamonds” at $12 billion this year, according to a Bloomberg report.

The Yen has fallen 18% against the dollar this year, which pushes up the cost of diamonds and gold in local terms and deters demand for new diamond pieces.

De Beers and other forecasters are looking for the market to pick up this fall for the September Hong Kong show and the run-up to the U.S. holiday season. @chapter:38


Publication Year: 1981 Title: Gem Garnets in The Red-To-Violet Color Range Abstract: The gemological classification of garnets has been thrown into question with the appearance on the market of new types of garnets that do not fit into the traditional system of description. The question of what criteria should be used to classify both old and new types of garnets is approached in this article through the study of 96 red-to-violet gem garnets. While the color of gem garnets is of paramount importance, color being both their most obvious feature as well as their principal claim to beauty, this article shows that the characteristic of color appears to have little correlation with variations in bulk (not trace) composition or physical properties. Analysis of the gemological properties, chemical composition, and CIE color coordinates of the stones studied led to the more specific definition of the widely accepted terms pyrope, almandine, and rhodolite for meaningful gemological classification. This article represents the first in a series of studies aimed at developing an effective terminology for the characterization of gem garnets. @chapter:6


Publication Year: 2023 Title: The history of gemstones in Chanthaburi_15 Abstract: Gemstone wells come in 3 types, distinguished by the soil characteristics where they are excavated. Alluvial gemstone wells are found in loamy soil and can be quite deep, reaching depths of up to 8 meters when dug into mountainous areas. Rock-type gemstone wells are not as deep as alluvial ones. Another type is the water-based gemstone well, which typically consists of clay soil. It requires a careful digging method for quick and easy excavation due to its sticky soil nature, allowing  for large chunks to be extracted. However, there is a risk that it may flow or collapse more easily compared to other types of gemstone wells. @chapter:25


Publication Year: 1988 Title: Detection of Treatment in Two Unusual Green Diamonds Abstract: A pair of sharp absorption bands in the near-infrared region, referred to as H1b and H1c, have been detected in one (and the H1b band in the other) of two green diamonds known to have been treated. Until now these bands have been associated with the annealing of yellow to brown laboratory-irradiated diamonds. This is the first reported observation of these bands in green treated diamonds. Although these two diamonds may represent a special case, in that they are believed to have been irradiated, annealed, and then re-irradiated, the presence of one or both of these bands in a green diamond is one of the few reliable characteristics that identify that the stone has been treated in a laboratory. @chapter:11


Publication Year: - Title: Alice Keller Abstract: For more than 30 years, the beauty of science has found expression in every issue of Gems & Gemology, thanks in large part to one influential editor and innovator, Alice Keller. Readers of G&G today can see Keller’s imprint on every page.

G&G was established in January 1934 as a source of research for both gemologists and the retail jewelry industry. From 1934 to 1980, GIA’s flagship publication was directed by two editors-in-chief: Robert Shipley and Richard Liddicoat. Over the decades, the journal kept its original unassuming size (5.5 x 8.5 inches) and format (black and white, with few photos). Although G&G published groundbreaking research and content, it needed an overhaul to capture the attention of the gemological community.

With an eye toward redesigning the journal, Liddicoat chose Keller, who had a decade of experience editing professional journals, to become the managing editor of G&G. Under Keller’s leadership, beginning with the Spring 1981 issue, G&G blossomed into an 8.5 x 11 inch, full-color publication that drew praise for its breathtaking color photography, including a two-decade run of covers by renowned photographers Harold and Erica Van Pelt.

Keller also established a peer-review system to ensure the quality and accuracy of articles, cultivating an editorial review board that included internationally prominent gemologists and researchers. Under Keller, G&G published pivotal research on synthetic diamonds, diamond treatments, and an array of colored stone topics. Her efforts culminated in widely read, award-winning articles and greater attention to gemology as a science. The journal’s multiple accolades and awards during Keller’s tenure reflected its international reputation as the industry’s leading source of cutting-edge research.

Always looking for ways to showcase important information, Keller spearheaded the publication of the three-volume Gems & Gemology in Review series, a comprehensive selection of the most significant G&G articles on synthetic, treated, and colored diamonds.

After 22 years of service, Keller became editor-in-chief of G&G in 2002, navigating the journal into the electronic age with the same insistence on excellence and attention to detail she devoted to the print version. In addition to her editorial duties, she co-chaired GIA’s International Gemological Symposiums in 1999, 2006, and 2011.

One of GIA’s Staff of the Year recipients in 1991, Keller also earned an Excellence in Publishing award from the Women’s Jewelry Association and an Honorary Lifetime Membership from the American Gem Trade Association, both in 1998. She received GIA’s highest honor, the Richard T. Liddicoat Award for Distinguished Service, in 2003.

Alice Keller retired in 2011, but remains the journal’s editor-in-chief emeritus. Under her leadership, G&G changed the face of gemological publications. @chapter:24


Publication Year: 2023 Title: Exploring the market direction of pearls and jewelry in Australia. Abstract: The jewellery market in Australia has been adversely affected by challenging economic conditions, including inflation and rising living costs. This has prompted Australian consumers to be cautious with their spending, significantly reducing expenditures on non-essential goods and services, particularly jewellery and accessories.
Most jewellery retailers in Australia are concentrated in densely populated areas with high foot traffic, primarily in the states of New South Wales, Victoria, and Queensland, which together account for more than three-quarters of the country's population.
Key factors influencing the jewellery business include international tourism, consumer confidence, and household income. Sydney stands out as a crucial city for jewellery businesses due to its ability to attract a large number of international tourists, particularly affluent ones, thereby supporting continuous business expansion.
The majority of players in the jewellery market (over 60%) are small-scale operators, such as sole proprietors and family-owned boutique stores, focusing on niche customer groups and the local market. They emphasize ethical jewellery and gender-neutral options. In contrast, major players, constituting less than 40%, prioritize tracking market trends to adapt business operations and product designs continually to meet consumer demands. For instance, current trends among Australian couples highlight a preference for less expensive engagement and wedding rings, influenced by changes in lifestyle due to the COVID-19 pandemic, which reduced social gatherings and large events.
Looking forward, the Fine Jewellery market segment remains crucial due to its consistent high pricing and timeless diversity. Operators in this segment place importance on monitoring market trends to ensure their business operations and product designs remain contemporary, meeting consumer needs. The Fashion Jewellery segment, particularly popular for items like gold-style minimalist earrings and pearls, remains highly favored due to its affordability and versatility, appealing to users aged 15-54, who can select based on fashion and personal taste. This segment primarily sells through online channels, alongside physical stores.
Overall, the Australian jewellery market, encompassing both Fine Jewellery and Fashion Jewellery segments, proves sensitive to various factors influencing consumer purchasing decisions. Success in this market requires stakeholders, including manufacturers, designers, and sellers, to carefully consider consumer sentiment and economic/social changes as critical variables for achieving business success and revenue generation. @chapter:27


Publication Year: 2023 Title: In Memoriam: Heitor Barbosa Abstract: Heitor Barbosa discovered Paraíba tourmaline in 1989 after almost a decade of mining. Photo by Duncan Pay.
The discoverer of Paraíba tourmaline, Heitor Barbosa (see above), died September 23, 2023, at the age of 90. Driven by intuition, Barbosa began his quest in the early 1980s at an old pegmatite mine in the Brazilian state of Paraíba. After several unsuccessful years and considerable skepticism from others, Barbosa prevailed and unearthed one of the world’s rarest gems—cuprian elbaite tourmaline—in 1989. Over the next two years, using simple hand tools and candles for lighting, Barbosa and his team recovered between 10 and 15 kg of the tourmaline characterized by its vivid blue and blue-green hues. Production slowed significantly in the years that followed, but Barbosa continued to work the mine, remaining hopeful that more tourmaline would be uncovered. Today, Barbosa’s son Sergio maintains the mine.
Barbosa is survived by his wife, four children, and two grandchildren. We extend our condolences to his family and friends. @chapter:3


Publication Year: 2018 Title: Fracture-Filled Diamond with "Rainbow" Flash Effect Abstract: Figure 1. Large fractures in this diamond are exposed in high relief before treatment (left). After the fractures are filled, the same stone has a much improved apparent clarity (right). Photos by John I. Koivula.
A loose diamond submitted for a diamond grading report is evaluated and given a grade on a scale relative to each value factor. Clarity, defined as a diamond’s relative freedom from inclusions or blemishes, is graded on a scale of Flawless (least included) to I3 (most included). The most common inclusions in diamond are crystals, which are contained entirely within the stone, and fractures—also known as feathers—which are surface reaching. Various clarity treatments exist to mask or remove undesirable inclusions because high-clarity diamonds are considered more valuable. Some diamond clarity treatments are permanent, while others are not and may change drastically in appearance with time or improper care. For this reason, GIA does not issue grading reports for diamonds that have been treated with unstable, non-permanent treatments. Acceptable treatments such as laser drilling and internal laser drilling are always clearly disclosed on grading reports.

Figure 2. The classic flash effect appearance: a pink flash in darkfield lighting (left) and a complementary green flash in brightfield lighting (right). Photos by John I. Koivula.
One such unstable treatment is fracture filling. Large, deep fractures in a diamond will often appear white or reflective due to the difference in the refractive index of the diamond and the air within the fracture. In an effort to disguise this, a substance with a refractive index similar to diamond’s, such as highly refractive lead glass, is introduced into surface-reaching fractures to reduce the interference of air (figure 1). Several telltale signs, such as the flash effect, typically reveal the presence of a filled fracture. The classic flash effect displays a vivid pink color in darkfield illumination and a complementary green color in brightfield illumination (figure 2). In a different orientation in brightfield lighting, a filled fracture can also appear bright blue.

Figure 3. A face-up view of the near-colorless 1.21 ct fracture-filled square modified brilliant cut. Photo by Robison McMurtry.
A 1.21 ct near-colorless square modified brilliant diamond was recently submitted to GIA’s Carlsbad laboratory for a diamond grading report (figure 3). It was rejected for grading after examination revealed a large filled fracture. Interestingly, the flash effect looked noticeably different from the classic appearance described above. Rather than flashing a single color in darkfield lighting and a single complementary color in brightfield lighting, this filled fracture flashed multiple colors in darkfield and multiple complementary colors in brightfield (figure 4). The unusual effect may be due to a difference in ingredients used to manufacture the filling material. To the untrained eye, it could easily be mistaken for the natural iridescence very commonly seen in unfilled fractures. However, such iridescence typically appears when the viewing angle is nearly perpendicular to the fracture, while the flash effect is most visible when the viewing angle is nearly parallel to the plane of the fracture. In addition to the “rainbow” flash effect, this filled fracture showed a dendritic pattern at the fracture opening that is caused by air pockets in the filling substance (figure 5). This pattern is characteristic of incomplete fracture filling (J.I. Koivula, The MicroWorld of Diamonds, Gemworld International, Inc., Northbrook, Illinois, 2000, pp. 106–108) and provides further evidence of the treatment.

Figure 4. When viewed nearly parallel to the plane of the fracture, this filled fracture exhibits a multicolored “rainbow” flash effect in both darkfield illumination (left) and brightfield illumination (right), as opposed to a classic single-color flash effect. Photomicrographs by Nathan Renfro; field of view 2.21 mm.

Figure 5. In addition to a “rainbow” flash effect, this filled fracture displays a dendritic pattern (and its mirror reflection) at the opening of the fracture. This pattern occurs as a result of incomplete fracture filling. Photomicrograph by Nathan Renfro; field of view 1.83 mm. @chapter:31


Publication Year: 2021 Title: Calcareous Coral and Epoxy Composite Abstract: Figure 1. The carved bangle submitted as “red calcareous coral.” Photo by Shu-Hong Lin.

Red calcareous coral is very popular in the Taiwanese market and has become far more expensive over the decades due to limited production and increasing demand. Red calcareous coral is usually cut into polished branches, beads, carvings, or cabochons. Recently, a bangle was submitted as calcareous coral to Taiwan Union Lab of Gem Research (TULAB) for identification service. It had a typical coral-red color (figure 1), though it was unusual to see a carved bangle due to the sizes of natural coral specimens that are found.

Figure 2. Short-wave ultraviolet fluorescence of the bangle presented a pattern of separate patches fluorescing white to orange. Photo by Kai-Yun Huang.
Standard gemological testing revealed that the refractive indices of this bangle were consistent with calcareous coral, at 1.48–1.65. However, its specific gravity of 2.27 was less than that of calcareous coral (2.6–2.7). Moreover, the short-wave ultraviolet fluorescence of this bangle presented a unique pattern of patches with chalky white to orange fluorescence next to each other (figure 2). Microscopic observations indicated that the patch-like fluorescence seemed to correspond to fragments of red calcareous coral, while the fragments were bonded with red material in which few bubble inclusions were found (figure 3).

Figure 3. The microscopic image of the carved bangle indicated that the fluorescing patches seemed to be fragments of red calcareous coral, while the gaps between the fragments were filled with red foreign material with few bubble inclusions. Photomicrograph by Yu-Shan Chou; field of view 5.46 mm.

Figure 4. The Raman spectra of the bangle matched those reported in the literature for red calcareous coral and epoxy resin, which meant the bangle was composed of fragments of red calcareous coral (A: Raman peaks at 704, 1087, 1128, and 1515 cm–1) and epoxy filling (B: Raman peaks at 638, 822, 1112, 1183, and 1606 cm–1). The stacked spectra are baseline-corrected and normalized.
To further confirm the identity of this bangle, the patches and the bonding material in between them were analyzed by Raman spectroscopy, and the resulting spectra were then compared with those of epoxy and red calcareous coral reported in the literature (figure 4; see K.E. Chike et al., “Raman and near-infrared studies of an epoxy resin,” Applied Spectroscopy, Vol. 47, No. 10, 1993, pp. 1631–1635; S. Karampelas et al., “Identification of the endangered pink-to-red Stylaster corals by Raman spectroscopy,” Spring 2009 G&G, pp. 48–52). The results showed that the fluorescing patches were natural calcareous coral, while the bonding material in between was epoxy resin.
This kind of composite product was likely made by bonding the stacked coral fragments with red epoxy resin to form a bulk material, which was then processed into carvings, cabochons, or even bangles. Although the coral-epoxy composite product looked similar to natural calcareous coral, it could be accurately distinguished through specific gravity, ultraviolet fluorescence reaction, microscopic observation, and Raman spectroscopy. @chapter:40


Publication Year: 1989 Title: The Gujar Killi Emerald Deposit, Northwest Frontier Province, Pakistan Abstract: Over the last decade, Pakistan has developed into an important source for many gem materials. A number of localities have been identified for emeralds in particular. This article reports on the emerald deposits in the valley of Gujar Killi, located in the Northwest Frontier Province. The occurrence, mining, and gemological properties are described. Reserves appear to be good, and increased mining activity suggests strong production for the near future. @chapter:1


Publication Year: 1994 Title: Spring 1994 G&G Lab Notes Abstract: Centenary Diamond Graded
"Unnamed Brown" Diamond
Fancy-Colored Rough Diamond
Characteristic Inclusions in Fancy-Color Diamonds
Feldspar and Garnet Snuff Bottle
Magnetic Hercynite
Impregnated Lavender Jadeite
Translucent Greenish Blue Opal
Early Japanese Assembled Cultured Blister Pearls
Experimental Nucleus in a Cultured Pearl
Star Sapphire with a Buff-Top Cut
Color-Change Synthetic Sapphire with Unusual Backing

To view the full section, download the PDF above. @chapter:32


Publication Year: - Title: Bench Tip #17: Avoid Stone Loss with Quality Assurance Benchmarks Abstract: Avoiding Stone Loss

Fine jewelry represents much more than its trade value in diamonds, gemstones and precious metals. It is a personal representation of the owner’s lifestyle, status, emotion, recognition, commitment and more. That significance only amplifies how devastating the loss of a gemstone is for the owner. Even one missing accent stone renders the jewelry unwearable. Loss of a significant gemstone will also impact the retailer who sold the piece and the manufacturer who engineered and produced it.

The loosening, damage or loss of gemstones in jewelry can be attributed to two factors: poor workmanship or the absence of benchmarking standards for setting. Benchmarks are specific parameters used to compare and evaluate the acceptability of a finished product for market.

Stone loss can be avoided. Inspecting each piece and comparing it against established benchmarks for signs of vulnerability in normal wear gives the jeweler/manufacturer an opportunity to address potential problems before jewelry is offered for sale. Adopting consistent task-specific benchmarks encourages sound design and good workmanship, assuring the quality of jewelry for the consumer.

Examples of the quality assurance benchmarks presented here are for setting round brilliant gemstones in traditional angled prongs.

	This drawing shows benchmarking criteria for angled prongs on a center stone.
Prong Setting Benchmarks – Traditional Angled Prongs

A:  Prong angle is 70-80 degrees.

B:  Sufficient prong thickness is needed to secure the stone in place, so 40-50% of the metal is removed from the prong thickness at the bearing.

C:  Diamond is seated level in the bearing just above the gallery wire. There are no gaps in any bearing – the bearing is the cut made in a prong and must precisely fit the stone contour when properly set. Any gaps will allow the stone to move or loosen.

D:  Finished prong height is 75-85% of table height. Ample prong height allows the prong to hold up through normal wear.

E:  Prong contact is 33-50% of total crown distance. Adequate prong contact over the crown is critical to a stable setting.

F:  Prongs are rounded, polished and consistent in size and shape.

Potential Errors in Workmanship for Traditional Angled Prongs
Example 1: Using benchmarking quality assurance benchmarks, you will note a bearing was not cut (lower blue arrow) and the diamond is not seated. Prong contact is insufficient (upper blue arrow) and barely secures the diamond.

	This center stone has no bearing.
Example 2: The bearing does not conform to the crown and pavilion angles of the diamond, so there are large gaps. Too much metal was removed from the prong thickness.

	This prong is overcut and there is visible open space at the bearing.
Understanding what to look for and following consistent quality assurance practices will enable our industry to ensure that our global consumers have the best possible jewelry experiences. @chapter:28


Publication Year: 2020 Title: Spectral Analysis of Resin Imitation Ivory Abstract: Figure 1. The “ivory” items submitted for identification: a bracelet (left) consisting of 16 beads, 13.4 mm diameter each, and two seal stamps (right) measuring 20 × 80 mm each. Photos by Lai Tai-An Gem Lab.
The application of spectroscopic techniques in solving gemological challenges is becoming more routine since more data is needed than standard gemological testing can provide. For example, resin is composed of a variety of complicated chemical components and, while basic testing can identify whether the material is resin, further detailed examination must be undertaken to obtain the specific chemical composition.
A client submitted three “ivory” items for identification, a bead bracelet and two seal stamps (figure 1). This case is similar to the “resin imitation ivory with a pseudo ‘engine-turned’ structure” reported previously (Fall 2019 Lab Notes, pp. 419–421). Standard gemological testing revealed an RI of 1.54 (spot) and an SG of 1.23, with parallel linear striations, all very similar to the properties obtained from the samples in the case referenced above. Natural ivory normally indicates an RI of 1.54 (spot) and an SG of 1.85, with Schreger lines. By comparing with this case, further examinations were taken by the following procedures.
FTIR and Raman spectroscopy were used to analyze the differences between resin imitating ivory and natural ivory reference samples with a known provenance. These results were compared with those of the client’s submissions.

Figure 2. FTIR spectra of natural ivory (top) and this object “resin imitation ivory” (bottom) revealed different peaks.
As shown in figure 2 (top), mid-FTIR reflectance spectra from the natural ivory of known provenance revealed peaks at 1044, 1447, and 1559 cm–1 (related to biogenic hydroxyapatites); 1658, 2850, and 2919 cm–1 (consistent with collagen); and 3310 cm–1 (from CO32–) (Z. Yin et al., “A comparison of modern and fossil ivories using multiple techniques,” Spring 2013 G&G, pp. 16–27). The client’s resin imitations revealed peaks at 702, 1126, 1284, 1380, 1462, and 1730 cm–1, characteristic of ester group alkyd resins (figure 2, bottom) (S.M. Cakić et al., “Investigation of the curing kinetics of alkyd-melamine-epoxy resin system,” Progress in Organic Coatings, Vol. 73, No. 4, 2012, pp. 415–424), and 2932 cm–1, consistent with CH stretching. These results were significantly different from those obtained from known samples of ivory, as detailed above.

Figure 3. Raman spectra comparing natural ivory (top) and “resin imitation ivory” (bottom) also revealed significant differences.
Raman analysis of the natural ivory revealed peaks at 428, 586, 852, 961, 1244, and 1664 cm–1 (figure 3, top), whereas the submitted resin samples displayed peaks at 621, 650, 1001, 1038, 1162, 1186, 1449, 1599, and 1724 cm–1 (figure 3, bottom). The spectra from each were sufficiently different to allow a quick and accurate separation.
These spectral comparisons provide readers with a reference when separating ivory from some resins. However, it is still important to apply standard gemological testing techniques during the initial examination while staying alert to the continual developments likely taking place with resin imitations. Spectral analysis plays an essential role in the differentiation process, especially in cases where more care may be needed. @chapter:37


Publication Year: 2019 Title: Book Review: Narrative Jewelry: Tales from the Toolbox Abstract: By Mark Fenn, hardcover, 304 pp., illus., pub. by Schiffer, Atglen, Pennsylvania, 2017, US$60.00.

The best jewelers know that every jewel has a story to tell. When Mark Fenn explored jewelry with a message for his dissertation at the University for the Creative Arts in England, things blossomed. The dissertation resulted in the curation of a collection of narrative jewelry for an online exhibition. His call to artists drew 350 jewelry artists from around the world who submitted 1,500 images. He narrowed these to 450 images from 241 artists. The results fill this beautiful and thought-provoking coffee-table book like a smorgasbord.
The stories contain themes as old as time, thoughts on contemporary society, and everything in between. Topics include mementos mori (symbols or reminders of death), historical reflections, feminist issues, global warming, and AIDS. Artists are arranged alphabetically with biographies, and each piece of jewelry is accompanied by the artist’s statement of meaning. It’s art as jewelry and jewelry as art, as well as jewelry as small sculpture.
The cover image, a brooch by Dauvit Alexander of Birmingham, England, is a gothic take on the kilt brooch known as a penannular. Titled “Blood Will Have Blood: A Macbeth Brooch,” its inspiration is from Act 3, Scene 4: “It will have blood, they say; blood will have blood.” Alexander, a self-taught jeweler who originally trained as a gardener, focuses on men’s jewelry. He used as a base a found, corroded iron oil tank cap and set into it polycarbonate reflector materials, faceted garnets, and strawberry quartz, with a surround of projecting black spinel points—all around the centerpiece, a carved black obsidian skull.
Melinda Risk has taken a high jewelry approach to the story of the Osmia avosetta bee, a species discovered in 1997. This bee lives a solitary life and nests in flower petals. Risk, who has a degree in jewelry from Kent State University, has created the bee’s story in a beautiful ring, the “Osmia Avosetta Bee Ring.” The bee image is back-carved into a Rose de France amethyst bezel set in 22K gold. Surrounding the center are small round diamonds set flush into the oxidized sterling shank. Down one side of the shank is a field of flowers with round pink sapphires in each one, while on the other side of the shank is a raised drawing of a bee. As a crowning touch, crushed dried flower petals are set beneath the center stone.
The jewelry design of Helen Noakes of Salisbury, England, is represented by two pieces: a bangle bracelet and a pendant, both executed in resin and silver. “Quantum Leap,” a whimsical pendant, depicts three tigers jumping through a “hoop” of clear resin bounded by silver, the first and last tigers half in and half out of the hoop. “Solo Voyager” features a tiny plastic scale-model polar bear trapped in an icy-looking resin bangle. She means it as a commentary on the disappearing habitat of the bear. She calls herself something of a choreographer, placing figures in the scenarios she creates.
Fenn has included his own work in this collection, a trio of sterling brooches done in a variety of processes. They are memento mori pieces, and here they deal with his sense of grief over losses. Fenn bases these brooches on the Bible’s apocalyptic Book of Revelation (6:8: “…behold a pale horse…”). While a heavenly sense of a floating city pervades all three, they each tell a particular story, two with horses and one with a robed ghostly figure.
Rudee Tancharoen of Thailand takes a conceptual approach to her silver jewelry. “Armonia” is a pair of mismatched silver earrings. One is a vertical black cylinder on a silver hook, while the other features three wire circles on a darker hook, loosely attached in a triangular configuration with jump rings. These spare earrings have their genesis in Tancharoen’s thoughts about politics in these times. “A pair doesn’t need to be identical.…simply being together peacefully with or without harmony is the key.”
This is a sturdy, easy-to-navigate book. Fenn has done a wonderful job of including many different approaches, materials, and themes from artists from all over the world. Traditionally, many artists refrain from telling you exactly what their art is about, preferring to let the viewer have his or her own experience. But in this book most artists give the viewer a leg up on understanding work that might be inaccessible for some. For those who love sculpture, it is a way into the very small sculptures that are the jewels in this book. For lovers of fine traditional jewelry, this is an entrée to another way to think about jeweled adornment. This one will stay on its owners’ coffee tables. @chapter:16


Publication Year: 2019 Title: Ornamental Jadeites from the Levoketchpel Deposit in the Polar Urals of Russia Abstract: Figure 1. Five of the 10 jadeite samples from the Levoketchpel deposit (back row) and four jadeites reportedly from the Polar Urals (front row). Photo by Shunsuke Nagai.

Although most jadeites on the market are from Myanmar, other sources include Guatemala, Japan, Kazakhstan, and Russia. Russian jadeites have been studied using geological and petrological approaches (e.g., A.M. Fishman, Gems in the North Ural and Timan, Geoprint, Syktyvkar, 2006, pp. 1–88; F. Meng et al., “Jadeitite in the Syum-Keu ultramafic complex from Polar Urals, Russia: insights into fluid activity in subduction zones,” European Journal of Mineralogy, Vol. 28, No. 6, 2016, pp. 1079–1097), but their gemological characteristics are still unclear. To date, several jadeite deposits have been found within some ultramafic complexes at the Polar Urals (Fishman, 2006). In August 2013, the authors visited a closed jadeite mine at the Levoketchpel deposit in the Voykar-Syninsky ultramafic complex of the Polar Urals to collect samples (figure 1). Here we describe the gemological and trace element chemistry of these jadeites.

Figure 2. Left: A geological map of the Voykar-Syninsky ultramafic complex in the Polar Urals. Modified from Meng et al. (2011). A: A whitish jadeite dike within serpentinized peridotite at the Levoketchpel area. The hammer is 40 cm long. Photo by Dimitri Kuznetsov. B: A jadeite boulder with surrounding phlogopite-rich rock. Photo by Makoto Miura.
The jadeites were found as dikes within serpentinized peridotite (figure 2A). The Levoketchpel deposit was reportedly discovered in 1959 (V.F. Morkovkina, “Jadeites in the hyperbasites of the Polar Urals,” Izvestiya Akademii Nauk SSSR (Seriya Geologicheskaya), 1960, Vol. 4, pp. 103–108). Mining at this area was done on a small scale, and the quality was low. In the outcrop, the jadeite dike is surrounded by phlogopite-rich rock (figure 2B) and peridotite. The Levoketchpel jadeites are translucent to opaque, and whitish to pale green and vivid green with a mottled color distribution. The samples showed a mosaic to fibrous aggregate structure. We collected 10 samples from the jadeite dike (five of these are shown in figure 1) and rubbles produced during mining. For the gemological observation, advanced testing, and quantitative laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) analysis of trace elements, we prepared wafers and thin sections (figure 3). Standard gemological testing revealed RI values of 1.66 to 1.67 and hydrostatic SG values of 3.2 to 3.4. In a handheld spectroscope, the whitish and pale green zones in the samples showed fine chrome lines at 630, 655, and 691 nm, and the diagnostic 437 nm line. These results strongly suggested that the samples were all jadeite.

Figure 3. Two jadeite samples from the Levoketchpel deposit, measuring 3.4 cm and 1.8 cm wide. Photo by Shunsuke Nagai.
EDXRF testing also indicated that the samples were composed mainly of jadeites. The pale green jadeites were characterized by a low CaO/Na2O ratio of 0.20 to 0.26, and a relatively high Al2O3/Fe2O3 ratio of 11.03 to 20.14. The vivid green parts tended to be slightly rich in Ca (CaO/Na2O ratio, 0.32 to 0.34), and the compositional ranges are suited for jadeite (Al2O3/Fe2O3 ratio of 10.73 to 20.14). Vivid green zones were slightly higher in Cr2O3, 0.06 to 0.16 wt.%, than the whitish and pale green samples (Cr2O3 up to 0.01 wt.%).
Careful observation and Raman spectroscopic analysis suggested that the samples were mainly composed of fine jadeite grains with minor amounts of omphacite, natrolite, feldspar, phlogopite, zircon, and chromite. Natrolite was found as the interstitial phase between jadeite grains. Jadeite crystals surrounding chromite crystals tended to be rich in green color. This green color concentration around chromite crystals is probably due to chromium diffusion from chromite during the jadeite’s formation. The coexisting mineral assemblage observed is consistent with previous petrological studies (e.g., G.E. Harlow and S.S. Sorensen, “Jade (nephrite and jadeite) and serpentinite: metasomatic connections,” International Geological Review, Vol. 12, 2005, pp. 49–68). In UV-Vis spectra, vivid green regions of the jadeites from Levoketchpel show an Fe3+ band and strong chromium bands in the 550–700 nm range. Similar results were also reported from jadeites from the Polar Urals (A. Abduriyim et al., “Japanese jadeite: History, characteristics, and comparison with other sources,” Spring 2017 G&G, pp. 48–67).

Figure 4. Trace element characteristics of the Levoketchpel jadeites. (A) Primitive mantle–normalized trace element patterns for green jadeites. (B) Chondrite-normalized rare earth element (REE) patterns for green jadeites. The detection limit is shown by the gray dashed line. Samples in this study are shown in red and compared with jadeites from the Pusyerka deposit at the Syum-Keu complex, the Polar Urals (Meng et al., 2016), Myanmar, Guatemala, and Japan (Abduriyim et al., 2017; Abduriyim et al., unpublished data). Primitive mantle and chondrite values for normalizing are from Sun and McDonough (1989).
Trace element compositions (Rb, Sr, Y, Zr, Nb, Ba, and the rare earth elements Hf, Ta, W, and U) were analyzed by LA-ICP-MS for 10 samples (70 spots total). Four of the samples had both whitish to pale green and vivid green zones. Chemical analyses were conducted on five spots for each of these zones. The whitish to pale green jadeites were depleted in REEs, while the vivid green zones tended to be richer in REEs. We calculated the primitive mantle–normalized trace element patterns and the chondrite-normalized REE patterns (figure 4) of the vivid green Levoketchpel jadeites (W.F. McDonough and S.-S. Sun, “The composition of the earth,” Chemical Geology, Vol. 120, 1995, pp. 223–253) and compared them to jadeites with similar color ranges from another jadeite locality in the Polar Urals (the Pusyerka deposit in the Syum-Keu ultramafic complex; Meng et al., 2016), Myanmar, Guatemala, and Japan (Abduriyim et al., 2017; Abduriyim et al., unpublished data). The primitive mantle–normalized trace element patterns of the Lavoketchpel jadeites reveal strong positive anomalies of Sr, Zr, and Nb (figure 4A). Such enrichment of the large-ion lithophile elements (LILE) and the high field strength elements (HFSE) in jadeites have been reported previously in jadeites from other localities (e.g., G.E. Harlow et al., “Jadeites and plate tectonics,” Annual Review of Earth and Planetary Sciences, Vol. 43, 2015, pp. 105–138). In these patterns, green jadeites from each locality show a very close overlap. In the chondrite-normalized patterns, the Levoketchpel jadeites show a right-downward slope: the light rare earth element (LREE) La, Ce, Nd, and Sm concentrations tended to be higher than the heavy rare earth element (HREE) Eu, Gd, Dy, Y, Er, Yb, and Lu contents (figure 4B). The Levoketchpel jadeites are depleted in HREE relative to the Pusyerka jadeites. Jadeites from Myanmar and Guatemala have higher total REE concentrations than the Polar Ural and Japanese jadeites (figure 4B). Burmese jadeite patterns show a gentle right-downward slope from La to Lu, and Guatemalan jadeites tend to be enriched in HREE. The Levoketchpel jadeites and some Japanese jadeites display a similar slope in REE concentration, although the former tend to be relatively depleted in HREE. @chapter:37