GemNotes

BUYER’S GUIDE: PADPARADSCHA SAPPHIRE

This is the seventh in a series by Senior Editor Robert Weldon designed to help jewelers buy different types of gems.

What to look for: Only a very precious few sapphires may claim the lofty title of padparadscha. The name is often used inappropriately – sometimes to describe flaming orange sapphires from Africa. But padparadscha sapphires, members of the corundum family, must contain pink as well as orange. The two colors must mix delicately and proportionately and preferably should favor pink. The resulting mélange should yield the color of an Oriental lotus flower.

That brings us to the origin of this somewhat mysterious, awkward name. Padparadscha is adapted from padmaragaya, a word stemming from Sanskrit, Bengali and later Sinhalese references to the color of a lotus flower. Given that lotus flowers have some variation in color, there is a small latitude in the definition. Experts agree, for example, that some padparadscha

sapphires may have hints of yellow in addition to pink and orange.

In looking for the best color, it’s helpful to compare two or more stones. The gems are so rare that such a comparison is difficult, but it often separates “wanna-be” padparadschas from the rest.

Also view the gem in various kinds of light. The gem can take on a warmer, pinker (and more expensive) tone in certain artificial light.

Could be confused with: Several natural gemstones could be confused visually with padparadscha sapphires. But they can be separated quickly upon close examination. Here are examples:

  • Imperial topaz often boasts this color combination in its finest examples. But refractive index and specific gravity readings will separate the two.

  • Spinel may sport padparadscha colors, but it’s singly refractive (vs. corundum’s double refraction) and has different inclusions than corundum.

  • Some garnets (also singly refractive) with orangy colors may also be confused with padparadscha. A few malaia garnets may fit this category, for example.

  • Transparent, faceted rhodochrosite, morganite and tourmaline may combine pink and orange. Here, too, the refractive index, optic character, spectrum and inclusions provide clear identity. A microscope, refractometer, specific gravity liquids and possibly a spectroscope will all help to separate the gems.

  • Synthetic pink/orange corundums are more difficult to separate because they essentially duplicate the optical, physical and visual characteristics of the natural gem. Under fluorescent light, however, some pink synthetics glow strongly. Magnification may reveal the identifying characteristics of a synthetic: metallic angular platelets (platinum from the lab’s crucible where it was created); whitish, non-translucent globular inclusions; or finer “rain-like” inclusions indicative of synthetic flux. Be careful though! Wispy veils of flux often look very much like natural “fingerprint” inclusions in corundum. If you can’t conclusively identify natural vs. synthetic, send the gem to a qualified laboratory.

Enhancements: All natural fancy-colored corundum is routinely heat-treated, including padparadscha. The treatment helps to rid the stone of offending silkiness (caused by rutile needle inclusions) and helps to saturate the color. The treatment is not easily identifiable unless you can see partially dissolved silk under magnification or stress fractures caused by the incongruous heating of inclusions.

Sources & price: The major sources of sapphires are Sri Lanka, Madagascar, Russia, India, Burma, Thailand, Australia and the U.S. While classic padparadscha sapphires are best-known as coming from Sri Lanka, they are possible anywhere sapphires are mined. In the U.S., padparadscha colors have been reported in Montana, though in very small sizes.

The price for natural padparadscha is closely tied to the precise color (which already makes the equation a difficult one due to different people’s perceptions) and size. Prices for fine gems between 3 and 7 carats may reach $4,000-7,000 per carat.

Gemology: Refractive index is 1.762-1770. Specific gravity is 4.00. Hardness is 9 on the Moh’s Scale. Fluorescence possible – as a strong orangy red.

Care: Padparadscha’s hardness makes it suitable for any kind of jewelry. Ultrasonic cleaners may be used unless the stone has an obvious surface-reaching fracture.

GIA UPDATES COLORED DIAMOND GRADING

The Gemological Institute of America has introduced a new grading report system for natural colored diamonds. It’s detailed in the winter issue of GIA’s Gems & Gemology magazine in an article written by John M. King, James Shigley, Thomas Moses and

Yan Liu.

The new system assigns specific definitions to existing descriptions of natural colored diamonds – Faint, Very Light, Light, Fancy Light, Fancy Intense and Fancy Dark – and adds two others – Fancy Deep and Fancy Vivid.

“Natural color diamonds have become more prevalent and more valuable,” says the article. “As a result, every year thousands of colored diamonds are now submitted to GIA’s Gem Trade Lab for color of origin determination and color grade.” The value of such stones depends much more on the color than is true of colorless diamonds, where clarity, cut and color weigh equally.

The new system calls for stones to be viewed face up with an overhead light source. The hue (actual color), tone (lightness or darkness of that color) and saturation (strength or purity of the color) are determined using a color comparison system.

In grading the hue of colored diamonds, GIA retains past practice of putting the modifying color first (as in purplish pink or brownish yellow). This differs from colored gemstones because “in the diamond trade, the final hue name has significant commercial implications that do not necessarily exist in the colored stone industry,” says the report.

The tone and saturation grades (Faint, Very Light, etc., as listed above) are more complex. These now relate more specifically to values in the Munsell color system. The new Fancy Deep grade denotes a medium to dark tone and moderate to high saturation. The new Fancy Vivid grade denotes light to medium tone and very high saturation. “With these new color grades, highly colored diamonds will be given more accurate and more appropriate color descriptions,” says the article.

How it’s done: GIA developed the grading system so gemologists can use light sources, viewing environments and color-comparison systems that are widely available at affordable costs. However, says GIA, gemologists working on their own must keep their equipment and methods consistent. The report lists the very specific methods and equipment used to grade colored diamonds, including:

  • A consistent, standard light source with known illumination characteristics.

  • The observation should take place in a neutral color environment.

  • The positions of the light source, diamond and observer in relation to one another must be very defined specifically. (GIA modified a viewing box to be certain the observer could always view each diamond in the same position relative to himself/herself and the light source.

  • The diamond color must be compared to a standard color reference.

  • Observations must be made by a person with normal color vision.

  • Mounted stones are graded in a range, such as Fancy light Yellow to Fancy Yellow.

In preparing this system, GIA researchers compared some 3,000 colored diamonds. “In the past five years, the increasing numbers of colored diamonds sent to GIA for a laboratory report, and the broad range of colors we’ve seen have required us to enhance our system,” says John King, GIA lab projects officer and lead author of the report. “We want this system to be as familiar to the trade and as clearly understood as GIA’s D-to-Z scale for colorless diamonds.”

The GIA researchers acknowledge that “no grading system can completely capture the special character of an individual stone” or its appeal to the potential buyer. “But a meaningful color description is a critical communication tool for dealer and consumer alike.”

For a copy of the report, contact Gems & Gemology Subscriptions, P.O. Box 2110, Santa Monica, Cal. 90407; (800) 421-7250, ext. 201.

`IDEAL’ FUTURE FOR LAZARE KAPLAN INT’L.

Lazare Kaplan International, New York, N.Y., known for its Ideal Cut diamonds and its ventures in foreign countries, has suffered the same profit squeezes as other diamond companies in recent years. But LKI remains on track for long-term growth, says President Leon Tempelsman.

“We have kept our strategic plan and have grown,” he says, despite the clash of higher prices by rough diamond suppliers, rampant discounting by retailers and price-resistance by consumers.

Like most diamond companies, LKI has seen sales turn upward from the lows of 1991-’92. In fact, the company’s polished diamond sales rose 60% to $36.8 million in the first half of fiscal 1995 from the same period of 1994.

Still, profits remain in the doldrums, totaling only $1.3 million in the first half. The company hopes to counter this by focusing even more on its two-part operational strategy:

  • Invest heavily in establishing the Ideal Cut “Lazare” diamonds as a differentiated, quality product in the minds of jewelers and consumers. The goal is to break the cycle of discounting and commoditization of diamonds.

  • Globalize sources of rough diamonds and markets for the company’s Ideal Cut stones.

Disappointments and successes: One of LKI’s biggest disappointments was a much publicized agreement in 1989 to buy $20 million worth of high-quality rough diamonds from Endiama, the state diamond marketing arm of Angola in southwestern Africa. First, a new agreement between De Beers and Endiama quickly cut the rough available to LKI to a tiny fraction of that amount. Then a 1991 cease-fire in Angola’s long-running civil war gave thousands of illegal miners a chance to swarm over Endiama’s territory, reducing the “official” supply of rough diamonds to nearly nothing. When the war resumed, enemy forces poached diamonds to fund their battles.

“Perhaps after there’s a lasting peace settlement, we can resume,” says Tempelsman. “Sometimes you have to play your strategic cards over a very long time before you can see the benefits.”

Some other LKI sources have dried up also, lowering revenue from rough diamond sales from $82.2 million in the first half of fiscal 1994 to $51.8 million in the same period of fiscal 1995.

However, the problem obtaining rough diamonds hasn’t affected LKI polishing operations. In addition to a longtime cutting plant in Puerto Rico, LKI has set up diamond polishing factories in Russia and Botswana. These nations are the two largest diamond producers by value, and both have been eager to build employment and develop diamond industries around their resource.

LKI’s $3 million polishing plant in Molepolole, Botswana – the largest such facility in Africa – has been in full operation about 18 months. Tempelsman calls it a success. “We have 450 workers there doing everything: buying, sorting, marking and polishing everything from two pointers to large stones,” he says. “Productivity is good and growing on schedule. The [local] workers were largely untrained, but they learn very quickly.” The smaller diamonds cut at the plant are Ideal Cuts (“because they are most cost-effective in a lower-cost labor center”), he says, while the larger rounds usually are not.

The government owns a 15% share in the operation and has been very cooperative, says Tempelsman. When Tempelsman proposed the cutting plant in 1990, government officials said LKI sought allotments of rough diamonds from the country’s production to run it. However, all of Botswana’s yearly output of 16 million carats is under contract to De Beers’ Central Selling Organisation. De Beers did agree, however, to provide LKI with enough rough diamonds “to meet the financial and performance objectives set by the Botswana government.”

The Russian operation is much-less publicized. But it has had good success with producing commercial-quality larger diamonds for about five years.

Tempelsman says LKI’s parent company, Leon Tempelsman & Son, was one of the first to set up polishing operations in Russia. “We’ve been quite pleased with our relationship with the Russians,” he says.

Polished diamonds: Two trends of the 1990s seem to favor LKI, says Tempelsman:

  • Unlike the 1980s, consumers now favor quality over showy products, value over price.

  • Globalization of the business community has opened new sources and new markets.

LKI launched an advertising program for Ideal Cut Lazare diamonds in the U.S. shortly after Tempelsman and his father, Maurice, acquired a majority interest in Lazare Kaplan a decade ago. The message: Ideal Cut diamonds are more beautiful and have greater value because they are cut for light refraction rather than weight retention and have a larger face-up appearance.

Tempelsman believes people are getting the message. “American consumers may be buying less often than they did in the 1980s,” he says. “But they are looking for better-quality, better-value products, and this is where our diamonds are best-suited.”

He admits that profit margins for U.S. retailers and diamond houses may never be restored to the levels of the 1970s. But there are still profits to be made for those who understand how the market is structured today. “Consumers are more sophisticated and knowledgeable today,” he says. Better independent retailers can compete with mass merchandisers and win, he says, if they provide these consumers with the information they want and the styles they won’t find in mass-merchandise outlets.

Expanding: LKI’s first foray into international markets was in Japan. Sales rose steadily before Japan’s economic boom went bust in 1990. “Now that the Japanese economy has begun to expand,” he says, “we’ll benefit because consumers now have more money and also more sophisticated tastes.”

LKI also has expanded into Thailand, Singapore, Taiwan and Europe to take advantage of new markets and to reduce dependence on a single marketplace, says Tempelsman.

Along with Lazare Diamonds, LKI also has diversified into finished jewelry. Its line comprises more than 100 items that retail for $1,000 and up.

Meanwhile, Tempelsman says LKI and the industry in general have weathered the global recession quite well. And though he remains dissatisfied with low profits from selling polished diamonds, he’s optimistic. “When you look back at the wrenching economic times the world economy has moved through, it’s remarkable how well the jewelry industry held up. That gives us room for a lot of optimism for the future.”

INDIA PRODUCES COLORED PEARLS

Indian scientists have succeeded in producing light pink and light yellow freshwater pearls, reports Asian correspondent D. Wickramanayake.

Researchers at the Central Institute of Aquaculture near Bhubaneswar say they used grafting and shell implant techniques to produce the pearls in a variety of sizes, shapes and colors.

The researchers also say they’ve been able to produce nacre-coated images of Hindu gods and goddesses.

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