The recent article on synthetic diamonds in Wired magazine (September issue) has garnered a great deal of attention by the major print media and television networks over the past several weeks.

Gem synthetic diamond is an intriguing product, and the finished goods are certainly attractive materials. They should be. They have all the same optical, physical and chemical properties of natural diamond. Visually – even to the most experienced gemologists – they are indistinguishable from natural diamond.

Fortunately, we at GIA have stayed well ahead of the technology curve on synthetic diamonds for seven decades. Our first encounter came in the 1930s, when a scientist claimed he had created synthetic diamond. Through good science and hard work, GIA founder Robert M. Shipley and his son Robert Jr. proved the claim to be false.

In 1955, General Electric Co. scientists created the first-ever synthetic (industrial quality) diamonds, which we later characterized. And when GE announced the first cuttable gem-quality synthetic diamonds in 1970, we quickly provided identification criteria. Then, in the 1980s, when Sumitomo Corp. started selling gem synthetic diamond crystals for use as “heat sinks” in electronic equipment, we broke the news to the world with an in-depth 1986 article that clearly characterized the material and provided for conclusive identification of it. The following year, we worked intensely with De Beers’ research staff and reported on their synthetic diamonds, all produced for experimental purposes. Since then, we have reported regularly on synthetic diamonds in Gems & Gemology, including a comprehensive wall chart for the separation of natural from synthetic diamonds in 1995 and a landmark 1996 article by De Beers researchers on their detection instrumentation. To this day, we continue to keep the trade and the public informed—and confident—about our ability to detect gem synthetic diamonds, with an article in the Winter 2002 G&G (months before the Wired article) characterizing the new Gemesis synthetic diamonds and an August Insider report on the new single-crystal diamonds grown by chemical vapor deposition.

I hope that the media reports on synthetic diamonds mention the fact that the major laboratories can conclusively identify gem synthetic diamonds, that most of the material produced is still small and yellow in color, and that the sum of all commercially produced gem synthetic diamonds is but a minute portion of the entire worldwide diamond market.

For years, we have stated that there is nothing inherently wrong with synthetic diamonds. They are attractive and will no doubt find a market niche if they can be produced in sufficient quantities to warrant the huge investment necessary to create and sustain demand at appealing price points. Our view has remained consistent: The key is proper identification and distinction from natural diamond, as well as full disclosure in the marketplace. While the barrier to commercially produced gem synthetic diamond has been broken, our ability to identify the product has not. It is critical that we keep it so.

Retail sales continue to perform reasonably well in September, generating optimism within the trade that the fall season will be strong.

DIAMONDS: One very famous 6.1-ct. Fancy Intense pink diamond may be back on the market: Celebrity watchers speculate that Ben Affleck has split with Jennifer Lopez due to "second thoughts" about their wedding. The hoopla surrounding the pink “J-Lo” diamond has been one reason for a strong increase in demand for colored diamonds and a big boost for the “bling-bling” (flashy celebrity jewelry) phenomenon, according to industry sources.

De Beers LV, the company’s retail venture with the luxury marketer LVMH, announced that three diamond jewelry boutiques under the De Beers name have opened their doors in Tokyo.

De Beers chose to open these first outlets within major department stores, in line with the initial launch strategy in Japan of other prestigious brands, both to benefit from the heavy customer traffic of these stores and to generate high brand visibility. The department stores that have partnered with De Beers for the launch of the brand in Tokyo are Takashimaya, Matsuya, and Isetan, enabling De Beers to cover the three different shopping districts of Nihonbashi, Ginza, and Shinjuku.

COLORED STONES: Dealers report little decline in corundum demand thus far as a result of the beryllium diffusion controversy.  However, recent visitors to Bangkok say that treated goods remain common in the market—some properly disclosed and others not. Most of the treated goods are smaller stones and commercial qualities that usually do not go through labs.

The Burmese Freedom and Democracy Act of 2003, which imposes strict economic sanctions on the nation of Myanmar (formerly known as Burma), took effect July 29. Thus far, it has had little impact on gemstone imports into the U.S., despite dire warnings from gem dealers that the ban on trade would seriously disrupt gem imports from that country. This is undoubtedly because the vast majority of gems mined in Myanmar are sold through Thailand without country-of-origin certificates.

Madagascar, one of the world’s most prolific gemstone producers, has launched a $40 million project in cooperation with the World Bank to regulate its gem-mining sector and reduce smuggling. According to Paulo De Sa, the World Bank's project coordinator, the first phase has already been completed, with establishment of a mining code, a new investment regime for industrial mining, and a mining registry system whereby mining companies can get a permit within 30 days.

TRADE: Christie’s has begun promoting a “Private Jewelry Sales” service. While the practice of selling items outside their auction rooms is not a new one for auction houses, this is the first attempt by a major house to conduct a sustained, ongoing “private” trade in top jewels. Previously, most private sales consisted of placing goods that failed to sell at auction or finding specific items for select clients between sales.

François Curiel, who heads Christie’s International Jewelry Department, said, “Private jewelry sales have always been an integral part of our department.  However, we have decided to promote this service, as I felt it has a great potential and not enough clients were aware of it.

“Indeed, we have had more and more calls, particularly in America, from buyers who could not wait for the next auction or had something specific in mind which was not available in one of the forthcoming sales. By the same token, we were also approached by private collectors and dealers who wanted to sell items without going through a public auction.” 

RETAIL:  The national jewelry chains continue to turn in a respectable year.

Signet Group, which operates Kay Jewelers and Jared Galleria in the U.S., reported that its same-store sales increased by 2.8% overall during the first half of this year. In the U.S., which accounts for 71% of Signet's sales, same-store sales rose 3.1% for the second quarter and 2.1% for the first half of the year, the company reported.

Reeds Jewelers reported sales for the second quarter, which ended August 31, of $19.4 million, a 2% increase over the same period last year, despite a round of store closings. Comparable-store sales for the quarter increased 5% compared to the same quarter of the prior year.

MACRO: The Bank of Tokyo–Mitsubishi (BTM), which compiles a weekly index of chain store sales, projects September’s sales growth for large stores at 3.5–4.0% over the previous year. BTM, which reported an August sales increase of 5%, believes that the more sluggish growth is due to the fact that consumers have already spent tax rebate checks and have slowed mortgage refinancing.

Russell Shor
Senior Industry Analyst

Our initial examination with a microscope showed that the black material was homogeneous. We also noticed a few dull conchoidal fractures. A detailed examination with intense fiber-optic illumination revealed that the black-appearing hololith actually was dark brown, and there were indications of a layered structure. Using hardness points in an inconspicuous place, we estimated the Mohs hardness to be approximately 6. Next, we attempted to obtain a refractive index reading by carefully placing the back of the hololith on the refractometer in a small area where the white metal mountings were less obstructive; the result was a vague reading in the mid-1.5s.

On the basis of these properties, we determined that the hololith had been carved out of chalcedony. To support this conclusion, we analyzed the material with the Raman spectrometer. The presence of two distinct peaks, one at 1600 cm^-1 and the other centered at 461 cm^-1, identified the black material as chalcedony and indicated the presence of a carbonized compound (sugar). In addition, infrared spectroscopy showed two peaks at approximately 2235 and 2133 cm^-1, which—our research has found—indicate that the color is the result of treatment by sugar and acid (and/or heat). This material is typically known in the trade as onyx.

This entry was prepared by Karin N. Hurwit, John I. Koivula, Dino DeGhionno, and Philip Owens of the GIA Gem Laboratory in Carlsbad . For more updates from the GIA Gem Laboratory, see the Lab Notes section in the upcoming Fall 2003 issue of Gems & Gemology. To subscribe, visit Gems & Gemology online. Or contact Circulation Coordinator Debbie Ortiz at dortiz@gia.edu, or call toll free 800-421-7250, ext. 7142. Outside the U.S. and Canada, call 760-603-4000, ext. 7142.

An overhead light source, as provided by a fiber-optic illuminator, makes it easier to see surface characteristics. Some microscopes come with a small fluorescent light or allow attachment of one to the stage for this purpose. You can also use a desk lamp, can be used with a loupe. For the general observation of surface characteristics, however, a fiber-optic system like the FiberLite works best. It also serves as a versatile supplementary light source that is vital for some separations, especially of synthetics and treatments.

Varying the lighting or using lighting combinations such as darkfield and fiber optics together can have a dramatic effect on the visibility and appearance of characteristics, and what can be determined by examining them. Surface characteristics visible in reflected light are usually invisible in darkfield light. And internal characteristics visible in darkfield light are often invisible in reflected light.

Darkfield Illumination

An included crystal’s relief depends on its refractive index (RI), its degree of transparency, and often its color, especially compared to the color of the host gem. A cluster of moderately sized, colorless calcite inclusions in a blue sapphire might be much harder to see than a few black chromite crystals scattered around the interior of a pale green peridot.

Most included crystals are relatively easy to see with darkfield illumination. Other characteristics, like fluid liquid inclusions—pockets in gems filled with fluids and sometimes other materials—might require different lighting techniques because it is often difficult to see into their interiors using darkfield.

Horizontal lighting is a fiber-optic illumination technique, where a narrow "pinpoint" beam of light is directed toward the side of the stone. Aim the light straight at the stone or from an oblique angle. Pinpoint crystals and gas bubbles stand out as bright objects when viewed from above.

Brightfield Illumination

Brightfield illumination—sometimes called transmitted light—results from opening the light well’s baffle so the light is transmitted directly through the stone to your eye. To keep from being dazzled by the bright light, close the iris diaphragm so the opening is smaller than the stone. This will create shadowed transmitted illumination. If necessary, adjust the intensity of the light source with the rheostat.

If not properly controlled, brightfield illumination may make many inclusions look dark and featureless against an overly bright background. If it is shadowed by closing the iris diaphragm, however, it works well for seeing low-relief features like curved striae in flame-fusion synthetics. Curved striae are structures that represent the layers of crystal growth around the cylindrical or rod-shaped boule, which is a typical product of the flame-fusion process.

Shadowed brightfield illumination can be created by rocking and tilting the gem under darkfield lighting. This creates alternating dark and bright backgrounds that can be helpful for detecting flash-effect colors in fillers—seen principally in fracture-filled diamond and emerald—or determining if an inclusion is liquid, solid, or opaque.

Diffused Lighting

For diffused lighting, open the baffle and the iris diaphragm and cover the stage opening with a white, translucent material. Facial tissue or even the white plastic diffuser from the microscope’s overhead light source can be used. Diffused light can help to observe the contents of liquid inclusions in natural gems. It is especially good for detecting curved color banding in flame-fusion synthetics. And it is excellent for detecting uneven color zoning in some lattice-diffusion-treated corundum, where the facet edges stand out against the white background.

Surface-Reflected Lighting

Fiber optics, darkfield, brightfield, and diffused lighting make many inclusions easier to see, but surface-reflected light works better for blemishes and certain types of inclusions. To examine a gem’s blemishes, position the light source, which is usually the microscope’s overhead light unit (although fiber-optic illumination is actually more suited to this task and works much better), so the light reflects from the gem’s surface. The light should strike the gem’s surface at close to a 90° angle—this is called vertical overhead illumination.

Thin, flat inclusions—like the thin films seen in many rubies—are also easiest to see when light reflects from their surfaces. But you cannot use vertical overhead illumination to see internal characteristics like these because reflections from the gem’s surface block the view of the stone’s interior. Instead, you need to use a light source—such as a fiber-optic light—to direct a narrow beam of light at the stone from an oblique angle. Light entering the stone in this manner reflects from internal fractures, cleavages, and fingerprints, and makes them much easier to see without creating distracting surface reflections.

Polarized Lighting

Polarized light can be created by opening the microscope’s baffle and placing one polarizing filter over the light well and another between the stone and the objectives. Hold the second filter or attach it to the microscope just below the objectives. The microscope then functions as a magnifying polariscope.

Use this type of lighting to distinguish doubly refractive included crystals from singly refractive solid inclusions or similar-looking gas bubbles or fluid-and/or gas-filled cavities. Crystals might show interference colors, and are often surrounded by halos caused by strain, while cavities or gas bubbles won’t have these features.

You can learn more about the identification of gemstones in the GIA Gem Identification course. For information on GIA courses and diploma programs, click here, e-mail eduinfo@gia.edu, or call 800-421-7250, ext. 4001.

The contribution will help to provide scholarships for students who wish to be educated by the world’s foremost authority in gemology. The Galaxy Diamond donation will assist in building the Endowment Fund to provide a perpetual source of income for GIA Education and Research, with only the interest generated from the account being used to fund such efforts.

“Our gift will allow aspiring industry participants to benefit from GIA’s educational programs, as well as for GIA to broaden its educational offerings, breadth of courses, and diversity of students,” said Gutentag. “As our company celebrates its 20^th anniversary, we hope this gift will set an example for the rest of the diamond and jewelry community by illustrating the importance of supporting education and our industry.”

In recognition of the company’s generous gift, a classroom at GIA’s world headquarters in Carlsbad, Calif. will be named for Galaxy Diamond. GIA’s Chief Development Officer Linda Ellis-Harmeling said, “We are very thankful for Galaxy Diamond’s gift because it will provide wonderful opportunities for students who otherwise wouldn’t have been able to study at GIA.”

The League of Honor is a distinction reserved for industry leaders and organizations who have contributed $100,000 or more to support GIA’s mission as a nonprofit public service organization. Since 1995, more than 80 individuals from numerous companies in the gem and jewelry industry have been recognized at the annual event.

To learn more about the GIA Endowment Fund, contact Jane Lynch, GIA’s director of Institute Relations, by e-mail at jane.lynch@gia.edu, or visit GIA's Web site.

Aug. 4, 2003