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Cacholong Opal

Written by Modern Jeweler On May 2, 2013.

According to opal expert and author Allan W. Eckert, the Russian word for “beautiful stone” is cacholong. Funny thing, that also happens to be the name of a common opal variety known for its porcelaneous milky-to-creamy white color and smooth, ceramic surface. Occasionally, this breed of opal occurs in reds and yellows, as well as banded form, but it’s the all-whites-most of which come from Russian Federation states near the Caspian Sea-for which it’s becoming known and increasingly prized.

Okay, maybe prized is an overstatement-but nowhere near as much of one as it would have been five years ago before Italian and German designers started using it. Some of their creations caught the eye of Tiffany’s executive vice president Jon King, who suggested using the gem in a jewelry collection by architect and Tiffany designer Frank Gehry, who had already designed a Fossil watch and a brand-name vodka bottle.

King’s suggestion showed a keen awareness of Gehry’s architectural projects such as the Dancing House in Prague, the Stata Center at MIT, and the Weisman Art Museum in Minneapolis-as well as a good understanding of his unique, often whimsical aesthetics. Looking at his artfully misshapen row of office buildings in Düsseldorf with their white exteriors, one sees how King would have wanted to bring cacholong opal with its ivory color to Gehry’s attention. Both Gehry’s buildings and his Tiffany’s ring design share Lewis Carroll-like elements.

No wonder Gehry is both praised and pummeled for his work. Stuffed shirts think that bringing humor to architecture is heretically offensive and that his works are self-serving eyesores. But Gehry is no Milton Berle. He’s more of a Buster Keaton and the impact of his wittiest wonders is never that of slapstick. Such works elegantly, sometimes drolly combine couture and surrealism. “Looking at a Gehry office building is like looking at a skyline in a funhouse mirror,” says an admiring architect friend. “His lines are very daring and optical. He and his muse must laugh a lot together.”

I say all this because Gehry’s use of cacholong (it can also be spelled cachalong) opal is, as many of his buildings attest, as much-maybe even more-about form than function. Gehry uses this material much as he does titanium. He has taken all of its attributes and made them into virtues. Just as he celebrates the reflectivity of titanium in many of his concert halls, King says, “Gehry celebrates the soft, sleek shine of cacholong in his curvilinear ‘Torque’ ring for Tiffany.” As such, the ring is wearable sculpture-and may inspire some of our lapidary readers to invent accessories and ornaments of their own using this mineral as if it were a metal or material.

Now I know what some of you will say. With hardness between 5.5 and 6 on the Mohs scale, doesn’t making rings out of cacholong opal invite quick wear and tear? King says that none of the cacholong rings the company has sold have been returned and no complaints about their durability have been received. But if that’s not reassuring enough, keep in mind that Gehry also designed cacholong bangles for Tiffany. My point is this: Isn’t it time to cash in on cacholong? If you agree, read on.

RARE AND INEXPENSIVE

Cacholong opal is not readily available. Most dealers dismiss it as, in the words of a fellow writer, “fringe opal.” So calls to your regular opal suppliers for cacholong cabochons and carvings will most likely be unfruitful. Part of the problem may be that cacholong opal is not found-or, should I say, not actively mined-in Australia, Brazil, Mexico, and other important sources of commercial opal. Tiffany relies on Russia for its material, some of which may also come from Bulgaria, another oft-mentioned source.

Like hydrophane opal, cacholong is very porous and very thirsty. That is why it is famous for sticking to tongues. It loves water. No wonder cacholong is often confused with hydrophane. But while both are classified as “common opal,” they are different varieties. Eckert explains the difference in his superb book, The World of Opals, published by Wiley in 1997: “Where hydrophane clearly exhibits POC [play of color] when wet, cacholong does not.” In other words, if you immerse a cacholong opal in water, it will glisten but it will stay opaque and not show flashes of spectral color.

Until recently, cacholong did not have any extensive history of jewelry use except for one gray variety with a lustrous mother-of-pearl appearance that endeared it to German cameo carvers under the name of “perlmutter opal.” Otherwise, cacholong is an uncommon variety of common opal whose jewelry history largely begins in this still very-young century. Whether Tiffany’s use of it in one of Frank Gehry’s six or so design collections for the firm will advance the cause remains to be seen. Whatever happens next, however, Gehry’s use of cacholong opal marks an early, very promising pinnacle in its short career as a gemstone.

Burma Sapphire

Written by Modern Jeweler On May 2, 2013.

Three times since 1971, a sizeable Burma sapphire once owned by John D. Rockefeller Jr. and now named after him has come up for auction at Sotheby’s. All three times the stone was bought by the same New York fine gem specialist, Ralph Esmerian. So great is his esteem for the 62.02-carat emerald cut that he paid $2.85 million ($46,000 per carat) to reacquire it the last time the behemoth hit the block at a St. Moritz sale in February 1988.That was top dollar for a Burma sapphire then.And now.

Come to think of it, so was the $1.5 million Esmerian and his father paid for the stone in May 1980, as was the $200,000 they spent to obtain it in November 1971.

Some dealers versed in upper echelon sapphire don’t feel quite as keen as Esmerian about the stone. But that’s the funny thing about fine Burma sapphire. Unlike exemplars of the Kashmir variety, the best of Burma rarely elicit the same unanimity of praise from dealers.

But there are enough tastes that agree with Esmerian to make Burma sapphire a secure No. 2 on the totem pole of connoisseur preferences for sapphire-one notch below Kashmir’s best and one notch above Sri Lanka’s.

Still, what is it about Burma’s blues that leaves dealers divided in their opinions about it?

Seeing the Rockefeller sapphire answered these questions.

Royal Blue

At a glance, the Rockefeller stone explains why Burma’s blue is so revered. Its color is royal, vivid and electric. As striking, the blue is so rich that it seems to be deposited in solid sheets. Although fine Sri Lankan stones often exhibit a similar blue, their color generally appears more watery and less forceful. (Kashmir color is of a different-and, most agree, higher-order of magnificence: softer, lighter-toned, more velvety.)

So much for the considerable pluses of Burma blue sapphire. “The blue is a bit over-intense,” says Reggie Miller, the New York lapidary who recut the stone from 66.03 to 62.02 carats in the early 1970s. “It’s a problem with this breed that their color runs so strong, stones are often too dark.”

Miller’s observation is one Burma sapphires have encountered for a long time. No admirer of these stones, gemologist Max Bauer wrote in 1903 that their color “is usually so dark that they appear almost black.” Adding insult to injury, he next noted that “they are seldom comparable in quality with those from Siam (Thailand), and do not command a high price.” Although sapphires from Thailand’s nearly exhausted deposit at Chantaburi have long been admired, it is hard to believe that they once fetched more than Burma’s best. Were turn-of-the-century tastes so much different from our own? That’s the only explanation we can give for the sapphire value situation circa 1900.

Big Brother

To the average connoisseur, aesthetics debates over Burma sapphires may come as a bit of a surprise. Although Burma stones have been prominently featured at recent auctions, this country’s breed, in general, just doesn’t receive as much press as those of other origins. It is probably safer to assume that collectors have read more about long-running sapphire mines in Montana or newer finds in Nigeria than ancient deposits in Burma. Yet, amazingly, Burma stones nab sums of money second only to those paid for Kashmir stones. And they’ve been doing this for several decades.

So why don’t jewelers and collectors care all that much about them?

We think it is because Burma sapphires, as beautiful as they are, have long been overshadowed by the country’s stellar rubies-which come, like the sapphires, mostly from the legendary Mogok tract. According to Bauer, Burma’s late 19th century production of ruby exceeded that of sapphire by a ratio of 500-to-1!
There’s no reason to think the ratio has changed.

Pedigree Problems

Ironically, although jewelers don’t make much of Burma sapphires, chances are good that they’ve seen and possibly even sold them, especially if they’ve been in business for a while. That’s because a good many Burma stones look so much like ones from Sri Lanka that their origin doesn’t warrant much ado.

Or didn”t.

Today, being from Burma can justify such high premiums that some unscrupulous dealers hunt out imposter stones from Sri Lanka and sell them as Burma originals. The color, appearance and inner life of these pretenders are so similar to Burmese stones that gem labs have their hands full ferreting them out. That’s why it is nearly impossible to sell a Burma sapphire today without an expert opinion in writing that it is from Burma.

This doesn’t mean that some stones aren’t “classics” that reveal their Burmese origin the instant they are seen. “A certain number of Burma sapphires, like their brethren ruby, have an intense color that holds up under all lighting conditions-incandescent, fluorescent and daylight,” origin expert Cap Beesley of American Gemological Laboratories explains. “The color is very pure and punchy in a way that most of Sri Lanka’s are not.”

While classic Burma stones pose little or no problem for origin authenticators, they represent a relative handful of the stones that are sent to them for study. Most are too close to call. For the safety of their reputation, honest dealers simply allow buyers to assume such stones are Sri Lankan.

Burma Peridot

Written by Modern Jeweler On May 2, 2013.

In 1962, just before a military takeover of Burma and the abrupt closing off of the country, a New York cutter bought a large selection of very fine to superb 20- to 40-carat peridots there for $1.50 per carat.

Nearly three decades later, the only Burmese peridot he can find is decent but far from great, yet the price asked of him is 100 times that of Burma’s best before the country was shut off from the world. And, mind you, this is the cost to a seasoned haggler in Thailand, the next-door haven for Burmese gems. The lapidary says he can’t begin to figure out what consumers would have to pay today for the kind of top-grade material in sizes between 20 and 40 carats that he bought in 1962.

But even if he could, all the cutter’s estimates would be moot. “I can’t find any goods,” he complains. “Not in Asia or America.”
The paucity of fine large peridot comes, as is so often the case in the jewelry world, just when this gem is capturing lots of attention. Peridot’s status as the August birthstone, its pleasing green and its bargain price relative to its extreme scarcity in top grades make it possible for dealers who carry this gem to sell all the fine-specimen large stones they can rustle up from estates, auctions or each other.

“I wish I could lay my hands on enough large, clean and well-cut peridots to fill the calls I keep getting for it,” says a New York gem importer. ” The market wants peridot, but not the kind dealers can provide.”

What they can provide are smaller stones , generally under 3 carats, with a green highly reminiscent of a 7Up bottle, most of them from Arizona where peridot is plentiful. But it’s the wrong kind of plenty. Because America produces almost no large stones, peridot is rarely seen in solitaire or center stone jewelry. Rather, it’s used most frequently to lend accent or create a multi-color effect. It is highly doubtful that most jewelers have seen, let alone sold, a true connoisseur’s peridot. And unless a mineralogical miracle occurs, their chances of seeing one will become even slimmer.

Source Spots

Peridot, which is a member of the olivine family, depends on body mass for color beauty. Because large stones have become so rare, the green for which this gem has for centuries been praised, a hue one cutter likens to “late-summer grass,” is seldom seen these days.

So prized was this saturate green that one of antiquity’s favorite compliments to peridot was to mistake it for emerald. A few jewelry historians are now convinced that some, maybe all, of Cleopatra’s emeralds were peridots from an island off Egypt. One famous large gem adorning the shrine of the Three Holy Kings in the cathedral at Cologne was for centuries believed to be an emerald and only identified as peridot late in the last century.

Alas, this take-me-for-emerald green is almost never encountered in peridots under 10 carats. To find stones with such color, one long had a choice of only two sources where, for various reasons, production has been at, or headed toward, a virtual standstill in recent years: Egypt and Burma. In the past few years, a few large fine peridot have reached the market from a new deposit in Pakistan which could become an important new source for the gem. If peridot is to become a real option for connoisseurs, something needs to happen to increase supply from one, or all three, of these localities.

The oldest and most celebrated source nof fine peridot is St. John’s Island (also known as Zabargad or Zebirget) in the Red Sea, some 34 miles off the coast of Egypt. Although this deposit was worked for thousands of years, its exact whereabouts became something of a mystery for several centuries until being rediscovered in 1905. Shortly thereafter, production resumed, peaked by the late 1930s and tapered off to practically nothing in 1958 when the mines were nationalized. Although parcels of St. John’s peridot still come on the market now and then, it is not known if this is new or old material. Most assume it is the latter. That is why St. John’s Island has a mystique among connoisseurs for its peridot that is akin to that of Kashmir, a presumably played-out source in northern India, for sapphire.

No one is sure if Burma has also played itself out as a peridot source. Before a coup d”etat in 1962 that left the country a socialist totalitarian state controlled by its army, Burma was a thriving gem producer, principally in its north-central Mogok district not too far off from Mandalay. Almost 40 years later, Burma is an economic shambles. Given these facts, it would probably be safe to say that politics are the reason Burma no longer can be counted on for peridot.

Connoisseur Quibbles

The peerless reputation of Burma’s ruby, jade and cultured pearl has rubbed off on the country’s peridot, helping to heighten collector interest in it and make it worthwhile for dealers to search out specifically Burmese specimens. Nevertheless, traditionalists deny Burma peridot full parity with the Egyptian variety. While acknowledging its ideal color, they note that Burmese material is usually less clean and hence less brilliant than that from St. John’s. “Burma stones tend to have carbon spots and a “rain-like” texture in them that keeps a good number of them from being gems, ” the New York cutter says.

Gemologists variously describe this brownish, sometimes grayish texture as “dust” or “pepper”. But whatever it’s called, it can impart a sleepy or hazy appearance- not to mention an objectionably dark olive color- to a stone. Although specks are not always visible to the naked eye, you’ll probably see them if you look at a stone at 3x or 10x magnification with a loupe. For this reason, clarity is an extremely important factor when buying peridot.

When shopping for peridot, keep in mind that this stone is relatively soft (6 1/2 on the Mohs hardness scale) and should be spared rugged, regular wearing if mounted in rings. When the stone is bought loose, remind the setter that peridot is highly sensitive to rapid temperature changes. Many peridots have been destroyed at the bench because pieces containing them were dipped in a cold solution after soldering. One other caveat concerning jewelry repair: Peridots can lose their polish if they come in contact with commonly used hydrochloric or sulfuric acid.

Burma Jadeite

Written by Modern Jeweler On May 2, 2013.

Although jade is primarily associated with the Chinese, who have treasured it for more than 5,000 years, the gem owes its English name to a group of far less well-known jade aficionados, the Mayans of Central America. When the Spaniards arrived in Central America in the early 16th century, they found many Mayans wearing the stone to ward off or cure kidney problems. This talismanic use led the Spaniards to call the gem piedra de l’ejade, or ‘stone of the loins.” The French later shortened this to le jade.

The stone the Spaniards named in the new world was not the same as the nephrite jade revered in China at the time. It was its cousin: jadeite from Guatemala, a silicate of sodium and aluminum. Nephrite jade is a silicate of calcium and magnesium.

The Chinese were also about to encounter jadeite, from a new source of unrivalled quality: Burma. The encounter would change the world’s perspective on jade forever.

The Jade-Cutter’s Gamble

For centuries, Chinese poets linked jade’s attributes, such as its steel-like toughness, to those of the gods, while philosophers praised its virtues. So esteemed was China’s native jade, the nephrite variety, that its emperors, accorded divine rights, spoke their prayers through ceremonial jade discs.

But the most prized nephrite, a white diaphanous variety called “mutton fat jade,” was becoming scarce, and China’s master carvers were forced instead to work with the more common waxy spinach green nephrite. The green of this nephrite was no match for the green of the jadeite that arrived in China from neighboring Burma in 1784, after the two countries signed a trade pact. The Chinese called it te t’sui, which means “kingfisher feather,” because its intense vivid green conjured up the color intensity of that bird’s feathers (which are actually blue, not green.) This color, couple with the stone’s luster and translucence, captivated Chinese carvers and artisans immediately. Ever since, jadeite has been the jade of preference in China and the rest of the world. Today, nephrite is valued mainly for its antiquity, while jadeite is valued in and of itself.

A case in point: in 1965, a New York gem dealer bought an antique jadeite archer’s ring for $735. After he had it cut into four cabochons, he sold the resulting stones for $10,000. That result gives you an idea of the tremendous value placed on fine jadeite. As a result, Chinese dealers will gamble ten, even hundreds, of thousands of dollars on rough jadeite boulders weighing from a few kilos to hundreds of pounds that they think will yield superb stones. The boulders are sometimes even sold in a high stakes gamble based on the outward appearance alone. More often the boulder will have a small window polished in its side that gives a tantalizing clue to what the rest of the boulder may, or may not, contain.

Although Burma is the world’s source for fine jadeite, Hong Kong is the world capital for trading and cutting of the gem. Hong Kong dealers have developed a system of priorities for maximizing the potential of a rough boulder. If a piece is free from streaks and fractures, and is deep enough, it is earmarked for cutting into cabochons, the smooth domed oval shape that is set in rings, pendants, and earrings. Next come, in descending order of preference, bangles, beads, carvings, and the flat doughnut-shaped discs popular as pendants in Asia. Jadeite carvings, including Buddhas, animals, and crosses, are also popular talismans worn as pendants.

Judging Jadeite

Jadeite comes in many colors, including delicate lavender and a rusty red, but green is the color that is most coveted. Experts describe the ideal for this color in varying ways. One likens the finest green in jadeite to that of liquid Prell concentrate shampoo. Another to the ‘intense green shoots of a freshly seeded lawn.” Both are talking about what is called “imperial green” a color often compared to that of the finest emerald. Stones that exhibit a forest or spinach green is considered too dark, stones paler than a pleasing apple green are too light.

But quality in jadeite isn’t merely a matter of hue and tone. It is a function of several factors:

  • Color uniformity: Stones should be free of any blotchiness or unevenness in the color.
  • Translucency: Stones should be semi-transparent in natural light.
  • Clarity: Stones should exhibit a lustrous brilliance that some dealers describe as a glow.

When all these factors – hue, color uniformity, translucency, clarity, and brightness – are present to a high degree, prices for five-carat jadeite cabochons will reach tens of thousands of dollars in the few fine jewelry stores that carry them. Larger top-caliber stones between 10 and 20 carats could cost $100,000, or even more.

But don’t despair. Decent jadeite cabochons around 3 to 5 carats are available at a fraction of these prices. Of course, expect these stones to be more opaque than translucent, be darker or lighter in tone, be included and lack the high polish of the finest jadeite. For a couple of thousand dollars, you should be able to find nice, apple green stones with good translucency, clarity, and brightness.

One warning when buying jadeite: a lot of pieces, like most of what is found in Hong Kong’s open-air jade markets is dyed. Material treated by a new process of bleaching and dyeing, followed by stabilization with epoxy resin, is known as B-jade. B-jade can look a lot like fine natural jadeite, so make sure that you buy from a reputable source and have the natural nature of your jade guaranteed in writing.

But every piece of jadeite brings with it a traditional power to increase your well-being. Jade is one gem still worn today as much as an amulet as adornment. Millions of people wear jadeite to bring them good health and luck, even though its beauty would seem to be reason enough.

Brown Tourmaline

Written by Modern Jeweler On May 2, 2013.

If you think garnet is a complex gem, try figuring out to which of the many branches of the tourmaline family the bronze, butterscotch, and cinnamon tourmalines we’ve been seeing in heaping numbers lately belong. There are at least three slots open: dravite, uvite, or buergerite.

I’d never heard of the last of that trio until I read R.V. Dietrich’s The Tourmaline Group, published by Van Nostrand Reinhold in 1985. Described by the author as exclusively orangey-brown, he cites Mexico as the only known source for this species. But maybe buergerite has a new locality in Sri Lanka, source of this glorious gem with its uncanny resemblance to fireball citrine.

More likely, thinks the stone’s owner, dealer Dudley Blauwet, Louisville, Colorado, the stone is a dravite. That’s the varietal name most dealers use for the brown-drenched or brown-tinged tourmalines in their stock. But he leaves open the possibility that it could be uvite-ever since mineralogists identified some orangey-brown stones from Morogoro in Tanzania as predominantly uvite.

No wonder New York dealer Steve Stieglitz brushes off my questions about proper species names for brown tourmaline. “Dealers tend to call any tourmaline with a brown color component by the name of dravite,” he says. “Do we know for sure? No. The term has more to do with custom and convenience than gemology.” He’s right. As long as I can remember, dealers have been using dravite as a kind of code-word for brown. Obviously, this speech habit predates the recent time when brown became beautiful-thanks to the rising popularity of “earth tones.”

Why is dravite-or, to be safe, dravite-uvite-suddenly both very hot and very cool? Blauwet thanks East Africa for its recent geological generosity with regard to supplies of attractive brownish tourmalines. “I am lucky if I get four nice orangey dravites from Sri Lanka in a year,” he says. “But I have been getting hundreds of carats of orangey-brown to butterscotch to golden-orangey greens from Tanzania and Kenya.” These new brownish tourmalines are far cries from the bland super-numerous dravites of yesteryear which often looked like smoky quartz. Today’s dravites feature ‘spice colors” such as paprika, saffron, and cinnamon. No wonder some dealers liken them to honey-brown zircon or cedar-brown spessartite.

Riding Several Tailwinds

Brown tourmaline is never going to reach the stature of Paraiba tourmaline. But its strong family ties are enough for dealers like Stieglitz to feel confident elevating inventory levels of the gem from token to staple status. Why? Some think better dravite is a logical substitute for spessartite, the popular brownish-orange garnet which is in very short supply. And with prices of $50 per carat for fine brown tourmaline versus $200 per carat for comparable quality spessartite, any influx of the former would surely be welcome. There’s just one problem: killer earth-tone tourmaline is far from plentiful. But Blauwet has got his fingers crossed now that East Africa has joined Sri Lanka as a source for superb dravite/uvite.

Kenya’s and Tanzania’s new dravite/uvite is the latest in a series of sensational tourmaline finds that have acted as drum beaters for the species. Remember chromium-colored emerald-green stones from East Africa in the late 1980s? A dealer showed me a 10 carat chrome tourmaline that he later sold for $1,200 per carat. Next, Paraiba, Brazil, briefly showered the world with stunning copper-bearing electric blue gems. Chrome and Paraiba tourmaline conferred full precious-stone status on tourmaline. Now high-quality dravite could benefit from and add to the species’ new prestige. “Tourmaline is thought of as a very distinguished gem and dealers are starting to make the case for every other variety that produces attractive stones,” says Simon Watt of Mayer & Watt, Maysville, Kentucky.

And this is where the many varietal vagaries of tourmaline work to the advantage of the species as a whole. While dealers make fusses over specific varieties of garnet like spessartite, when was the last time you heard one boast about an elbaite? Elbaite is hot, but not under that name. You and I know its most beautiful colors as Paraiba.

But locality-based names for tourmaline are also rare. Tourmaline is usually labeled by color. So it is hardly surprising to see a flurry of freshly-coined market names such as “cinnamon” and ‘sunset” tourmaline. I doubt whether dealers and designers are going to stop this form of branding and adopt usage of the species name dravite, which sounds more like that of a language than a gem.

In his book, Dietrich opposes any kind of classification system for this broad gem group based on color names. His reason: There’s too much species overlap and identity confusion. But I think it’s too late for such objections. Tourmaline is a kind of melting pot gem. Granted, varietal names are occasionally based on trace elements as in the case of copper-bearing Paraiba wannabes from Mozambique which are now called cuprian elbaite. But, frankly, this has been done to cash in on the resemblance between African stones and those from the high-provenance locality of Paraiba.

So where do things stand with the budding market for brown tourmaline? At prices between $15 and $60 per carat, fine Sri Lankan dravite and East African uvite is worthy of trial use, says Jason Baskin, chief buyer for The Gem Vault, Flemington, New Jersey. “Using dravite is at this point more a matter of creating rather than responding to demand,” he says. “Instinct tells us that fine dravite is next in line for discovery by a public searching for beautiful new gems.”


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