VOL. 31, #1, Spring 2013

Tucson Gem Shows 2013, Tucson Gem Shows NY Times article, Two Blue Diamonds discovered, Auction News, In The News, Gem Prices Overview, Retail Gemstone Price Trends (1975-2012), Gem Robberies

  Apr 7, 2013   admin


TABLE OF CONTENTS


Tucson Gem Shows 2013
by Robert Genis

The Tucson Gem Shows remain the largest and best in the world. They last for practically a month, although the two main shows for high end colored gemstones only a few days. As a general rule, the first and last days are the busiest. Buyers either know what they want and demand first choice by buying early or buyers play a "cat and mouse" game and wait until the very end to make low offers. This year these buyers were in attendance, but the show had a more intense Far Eastern feel. Asian buyers, primarily Chinese, spent the show going from booth to booth purchasing something from every booth. This is unprecedented. I don't ever remember this type of mass behavior. The dealers were happy and had great shows. The Chinese, obviously would rather own gemstones than American dollars. Buyers this year had cash in hand and they bought goods. Except for Asian buyers, the dominant buyers were firms representing collectors or hedge funds, not the average retail jeweler. For some reason retail jewelers do not attend these shows like the old days, probably a sign of a really weak economy, as only the high end is doing well while the middle/lower end goods suffer.

Hot New Stone
No hot new stones were on display at the gem shows. However, a brand new find of African aquamarine was recently discovered and the rough was seen. It's a beautiful blue and reportedly not treated. Expect to see some large pieces and gemstone suites in the very near future. This relatively inexpensive stone should probably be bought by collectors on a limited budget or those looking to further diversify their portfolios. As always, the best comes out first at the lowest prices. Don't say we didn't warn you. Other stones of interest we saw included green tanzanite, color change garnet and untreated purple Burma sapphire. We also found some pretty light bright blue Burma sapphire. Spinel was another hot stone in the marketplace. It is now being seen as a real alternative to the embargoed and pricier Mogok Burma ruby. We still contend the best stones come from Burma not Africa. Stick with the gem reds, hot pinks and flame oranges. All these stones are excellent diversification gems for a well balanced portfolio.

Gem Market Overview
The high-end gem market remains strong. Prices are high and discounts are few and small compared to asking prices. Many dealers would rather wait for the Asian buyers to come to their booths than discount their material. After all, it's not like they can replace their goods at lower prices. If they sell, they must compete with Asian buyers overseas for the same material. Actually it's quite a dilemma for gemstone wholesalers. Many contend it is better to buy from old collectors or estate sales than travel internationally to source countries.

Conclusion
The gemstone market is now totally bifurcated. Despite an uneven worldwide economic recovery, the high end gem market continues to fly while the rest of the market suffers. We saw no indication of the high end market slowing down. Please see below regarding gem price overview and trends. Wealthy American, European and Asian collectors have an insatiable appetite for high end collectible gemstones.


Tucson Gem Shows NY Times
A Treasure on Every Table
New York Times
February 20, 2013
By Guy Trebay


How often do we see an article in the New York Times about the Tucson Gem shows? Pretty rare so here it is in it's entirety. ED

The earth is made of them and space is littered with them and, for two weeks every February, this city of roughly a half-million swells by another 50,000 as mineral hunters from around the planet descend on southern Arizona in passionate pursuit of more rocks.

They come in search of the usual mineral suspects: emeralds, sapphires, rubies mined all over and transported to a gem fair that is one of the biggest things to happen here each year.

They come, too, in search of specimens and oddities, rocks with unusual names and baroque formations: purple apatite from Panasqueira in Portugal; carrolite from the Democratic Republic of Congo; epidote from the famous Green Monster mine in Alaska; sacred Shiva lingams rolled smooth over eons by the Narmada river in India; meteoritic litter like the stuff that rained down on Deputatskoye, Russia, only last week.

The umbrella term for an annual trade fair that is a key destination on an international circuit is the Tucson Gem, Mineral and Fossil Showcase. The name scarcely hints at the scope of an event that takes over Tucson each winter — 43 shows in 41 locations, including hotels, motels, dusty parking lots, the city's big convention center and tent cities set up by frontage road along Interstate 10 - drawing dealers from China, Morocco, Siberia, Tanzania, Australia and India.

"There are dealers from literally all over the world," said Tito Pedrini, a New York-based jeweler who arrived in early February for the American Gem Trade Association, a high-end fair that people in his business scour for exceptional examples of the colored gemstones fashionable now among celebrities and the ultrarich.

"You think, ‘Why is the gem show there?' " Mr. Pedrini said. "Tucson is such a difficult place to reach."

What started 59 years ago as a show created by 18 local mineral enthusiasts and held in an elementary school has spread over the ensuing decades into a hunting ground for those looking to buy or sell anything from hulking geodes to a gumball-size Tsavorite.

Hardly a jeweler at work - from industrial Goliaths like Tiffany & Company and Bulgari to fashionable artisans like Mr. Pedrini, Ted Muehling, Susan Reinstein and Brian Ross of Reinstein Ross, or Ramji Bharany of the century-old Bharany's in New Delhi - has skipped a visit to Tucson.

The reasons are simple. Gem trends are set there. New strikes are showcased. Peculiarities like the remains of fossilized monkey puzzle tree that the Victorians called Whitby Jet and used to make mourning jewelry turn up again suddenly, ready to be back in style. Freakish deposits appear there, things like a hunk of fluorite the size of a kiddie pool, pried from a mine in England and sold for a six-figure sum before the fair began.

It is here that the miraculous and precious stuff teased from the grip of the earth or else winkled out of safe deposit boxes miraculously appears.

"New York is one of the centers for colored stones, and it's very easy to source them here," Mr. Pedrini said. "I wanted stones that are more rare, and to find those you need to go directly to the source," he added, referring to dealers in tourmalines or peridots or spinels or opals, precious minerals mined in places as politically and geologically disparate as Australia and Afghanistan.

"The Burma peridots, which people know better, are quieter and more silky," Mr. Pedrini said of a scarce green stone sometimes mistaken for emerald. "The Afghan peridots are sparkly and lively, more yellowish green." On his second day here, he came upon a fine 25-carat peridot that even in the midst of war was mined and exported from Afghanistan.

"You never know when there might be new finds in one particular area of the world, something different from the standard origins, and that provides renewal" to the jewelry trade, said Matthew L. Hopkins, a Rhode Island-based jeweler specializing in opals. The gems Mr. Hopkins had on offer come from a family-held claim in the Lightning Ridge region of the Australian Outback. In Tucson, renewal, or at least competition, unexpectedly appeared this year in the form of the Ethiopian dealers who have flooded the opal market since deposits of the silicate gem were discovered in the northeastern Wollo province in 2008.

"Probably 70 percent of the world's colored gemstones on the market pass through Tucson during the month of February," Mr. Hopkins said "Because the dollar is still not doing so well, our market is increasingly the middle class in Asia. The Japanese were really into opals in the '80s and '90s."

In that pre-recession era, dealers like Hopkins Opals could charge as much as $10,000 a carat for top-quality black opals. That price plummeted when the fiscally troubled Japanese dropped out of the market; luckily, Mr. Hopkins said, it was then that an emerging Chinese middle class appeared.

"The Chinese have not gotten stuck in the realm of ruby, sapphire, diamond," Mr. Hopkins said. "They have much more room for other stones."

Wandering the aisles of the Tucson Gem and Mineral Show, held in the city's convention center, Mauro Parietti and Davide Viale, a jeweler and a mineral aficionado from Italy, stopped to look in on Mr. Hopkins's booth. "You can never find any place else all the things you see here in one place at one time," said Mr. Viale, who shops for rocks on the basis of their aesthetic value, a practice less common than it might seem.

Collectors are as various as rocks, said Thomas Raber, a salesman at Wendel Minerals, dealers based in southern Germany. "Some want only very aesthetic pieces, some want to get only things from certain mines," he said.

"Some look only about rarity and some are systematic and collect only one kind of mineral," he added, pointing to the prize display in his booth, a grotesque group of naturally occurring "threads" of Saxon silver, found in an old German collection and dauntingly priced at about $58,000 each.

Some collect on the basis of emotion because, as Elizabeth Taylor, that incontestable authority on rocks, once told this reporter: "Stones have a life of their own. There's something mystical about them. They have their own vitality."

It was the vibrancy of a particular Tsavorite that struck Mr. Pedrini, the Manhattan-based jeweler, when he visited Bridges Tsavorites.

"I went in the morning, because your eyes are only good once, and so you should only look at gems then," said Mr. Pedrini, among the rare fashionable jewelers also trained as a gemologist. "And they brought out some stones, which were nice, and then this one that they told me is the most expensive and one they never show."

The discovery of Tsavorite, a form of garnet, is generally credited to Campbell R. Bridges, a Scottish-born, Kenya-based geologist and a legend in the trade. It was in the 1960s that Bridges stumbled upon the rock formations that yielded a stone new to the trade while scouting beryllium for the United Kingdom Atomic Energy Authority. "He was prospecting in Tanzania, and a Cape buffalo charged him," said his son, Bruce Bridges, 33. "So he dove into a ravine."

Walking to safety, Campbell Bridges (whose 2009 murder by assailants armed with arrows, spears and machetes, in an apparent dispute over mining rights, remains under investigation in Kenya) came upon something flashing green on the ground.

"It was unlike anything he had ever seen before," Bruce Bridges said.

Complex politics prevented the strike from being exploited for another decade and delayed the naming of the new gem until 1974. Mr. Bridges's wife argued for Campbellite (and the slogan "Campbellite by Candlelight"); ultimately Harry Platt, the head of Tiffany, prevailed, and the stone was called Tsavorite after the Tsavo River and the Tsavo National Park.

"It's still a very rare stone," said Mr. Bridges, who explained that to find a Tsavorite exceeding two carats is vastly less likely than coming upon a comparable emerald. And unlike emeralds, which are sometimes characterized as sleepy and which are by nature delicate, Tsavorite is a tough stone, colored so deeply that it can sometimes seem faked.

"The color of the stone I saw was deeply saturated, neon, electric," Mr. Pedrini said. "This is what happens in Tucson: you fall in love with stones you never knew before." For now, Mr. Pedrini's love for that particular Tsavorite must remain platonic: the cost of the 26-carat rock is about a half-million dollars.

"Now," he said, "I have to find a husband whose wife cannot live without the stone."

This article has been revised to reflect the following correction:
Correction: March 7, 2013
An article on Feb. 21 about the Tucson Gem, Mineral and Fossil Showcase referred incorrectly to a mineral deposit found in England. It is fluorite - not fluoride, which is a compound.


Two Blue Diamonds Discovered

A rough blue diamond weighing 4.77 and a smaller diamond weighing .20 were recently found by Lucara Diamond.

They were found in the Karowe mine in Botswana, Africa. This brings the total found in the last few months to four blue gems.

The 9.46 blue recently found was sold for $4.5 million


Auction News

Sotheby's NY February

Sotheby's Important Jewels sold over $10 million or 78% of the lots. Not a whole lot of quality at this show.

Here are some interesting pieces:

* 51 round Fancy Vivid Purplish Pink diamond sold for $338,500. The estimates were $60,000-$80,000. Round vivid stones are extremely rare and the GIA said the clarity was VS2.

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* 3.96 octagonal Burma ruby sold for $290,500 or over $73,000 per carat. The stone was graded by AGL but looked to have primary purplish color. The estimates were $150,000-$200,000.

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* 20.11 cushion Fancy Deep Brownish Yellow diamond sold for $230,500.

* 9.89 Padparadscha Sapphire sold for $92,500. It had a GRS grading report.

* 19.79 emerald cut Ceylon sapphire sold for $86,500. It was no heat according to AGL.

20130401-ceylonsapp.jpg

In The News

Coloured gemstones at auction: the next big thing
Professional Jeweller
February 28, 2013
By Kathryn Bishop


A British perspective about the rise of untreated colored gemstones at auction. ED

While large diamond sales typically win all the headlines, auction houses and stone dealers have noticed increasing demand for coloured gemstones, especially those that are untreated. Kathryn Bishop reports on the development of the trend and finds out whether Britain could position itself as a new international gem trading platform.

In May last year Bonhams New York announced that it was to hold its first ever gemstone and mineral auction. The reason? The auction house had recognised growing demand for such a specialised sale.

The auction was set to include packets of gemstones owned by London-based gemstone collector and retired jeweller Robert Wander, as well as exceptional stones weighing several hundred carats.

The results of the auction were eye-opening. Among the packets of stones, most of which sold for several thousand dollars, stood several large unmounted gems. It was the more natural of these that stood out and became the hero lots of the day, including a pigeon's blood Burmese ruby that, while only weighing 4cts, achieved a sale price of US$60,000 (£37,416).

A rare white natural non-nacreous conch pearl from a giant clam, totalling 32.45cts, also wowed with a hammer price of US$35,000 (£21,826).

This auction, which attracted international clientele, marked the evident desire for natural stones and a growing interest from collectors and investors.

Naturally Does It
In Europe a similar story is being woven at auction houses in Geneva and London. At Christie's London, head of jewellery Keith Penton says that the arrival of fine coloured gemstones to market often provokes anticipation among stone collectors, with a growing interest from overseas dealers or collectors helping to drive prices upwards.

"Collectors appreciate that the very best coloured [stones] are extremely scarce and if a fine unheated Burma ruby or Kashmir sapphire comes onto the market it always causes a lot of excitement," Penton says. "In recent years Asian and Indian buyers have been much more active in the salerooms and this has helped to push the market to new levels."

Former diamond dealer and jewellery auctioneer Joanna Hardy, who today works as a private jewellery consultant, explains that the scarcity of certain stones is what draws interest. "Unheated Burma rubies, Kashmir sapphires and Colombian emeralds that have not been enhanced have been achieving record prices because they are genuinely very rare," she notes, explaining that the rise in coloured gemstones under the gavel has brought other bright stones to the fore. "The demand for colour has meant that other gemstones have attracted the attention of the international buyer and such stones as Paraiba tourmalines, spinels, rubellites, pink sapphires and topaz, to name but a few, are being sought after by the discerning collector."

It is the natural stones, however, that win some of the highest prices; in particular those bought for investment purposes. Bonhams New York gemmologist and co-consulting director of its natural history department Claudia Florian explains that the reason for the explosion in gemstone sales is often due to baby boomers inheriting stones they have no need for, and can make a respectable sum from by selling, even during – or perhaps because of – tougher economic times.

Penton agrees that investment, or the funds gained from selling natural stones, is pushing more people to buy and sell. "There is a lot of interest in investment at the moment and collectors want to put their money into the very best gems available," he says.

Penton adds that, owing to the evolution of stone treatments, good laboratory reports are essential nowadays to reassure buyers. "As the level and type of treatments become more varied and more difficult to detect, the laboratories have responded to the need and the certificates contain more detail," he explains. "As more sophisticated treatments are developed, the more collectors focus on natural unenhanced gems."

London-based Gemfields has become recognised as a leading producer of emeralds and amethysts in the global marketplace, and this year is set to push into mining of rubies and sapphires. From its London office it has worked with clients across the world, teaming with Indian jeweller Amrapali for an ethical emerald line, and making its move into the US market last September. Its growth was reflected in its financial results last year, with profit up 140% year on year, with revenue from its emerald and beryl sales more than doubling to US$83.7 million (£52.2m).

Gabriella Harvey, director of cut and polished stones at Gemfields, notes that clients looking for gemstones understand their scarcity, especially following many years of large, fine diamonds being sold at auction. "Consumers are far more aware of how rare fine coloured gems are in comparison to diamonds – they are far more unique," she explains. "Emeralds for example, are 20 times rarer than diamonds due to their limited source."

Harvey agrees that rarity of natural stones – in particular emeralds, which are subject to treatments that have become expected, such as oiling to improve clarity – is a client preference. "It is about the naturalness of an individual gemstone, the preference will always be to have untreated stones in their most natural form – again they are rarer," she explains.

The UK's Role in Gems
With an increase in interest from collectors, dealers and investors at a global level, the market for fine coloured gemstones is ready for the taking. With producers such as Gemfields driving forward their sales, and with London home to some of the most exciting jewellery auctions and previews of the past few years - including the sale of the Duchess of Windsor's jewellery collection and the showcase of Elizabeth Taylor's jewels -  the potential for Britain to step into the spotlight as a leading trade platform is there.

Penton, who oversees the jewellery going for auction at Chrisite's London, views the British gemstone sales market as still in development, as Switzerland continues to reign as the country of choice for vast gemstone and jewellery auctions. "London is of course still an important hub and has a proven track record for achieving some of the best results when it comes to the sale of important antique coloured gems [but] for the past 43 years our biannual Geneva sales have provided the premier platform for the sale of the most important coloured gems that we offer in Europe," Penton notes. "There are a number of reasons [for this], including the convenient Swiss taxation system."

Christie's Geneva auction of Lily Safra's jewels in May last year, for example, was a white glove sale - meaning 100% of lots sold - totalling £23.4 million, far exceeding pre-sale expectations. Then in New York on December 10 Christie's sold some more important gems, including several unheated Ceylon sapphire rings with guide prices of $250,000 (£155,400).

While large stones are typically sold outside the UK, Hardy believes that there is potential to sell such stones in Britain. "There are auction houses all over Britain that would do well in concentrating on this area as I see it has great potential, so long as the quality of the stones offered matched the expectations of the international buyer," she says.

Demand for British Gems
Here in Britain a number of abundant and also rare homegrown gemstones and minerals exist, but many jewellers and designers often overlook the potential of tapping into the Britishness of such stones.

At CW Sellors, the Derbyshire-based jewellery manufacture, the promotion of British stones is very much part of its marketing and sales pitch. CW Sellors workshop manager Paul Barker explains that its focus on British stones has evolved over the years. "[We] initially worked mainly with Derbyshire Blue John, but over time CW Sellors has evolved and now works with a far wider portfolio of British gemstones," he says. "[We now work with] Whitby jet and most recently Preseli Blue Stone, plus we have also worked with marbles and granites from all over the UK for many years."

The use of British stones comes with its fair share of challenges, however, from both a supply angle and a practical one. "You need to have jewellery technicians and designers who understand the unique properties of the stone," explains Barker. "It is key for us to educate customers [so] our products are all provided with informative stone cards which explain the heritage of the particular stone bought. We also run talks about Whitby jet on a regular basis and are planning more Blue John talks in the future."

Gemstone wholesaler Marcia Lanyon works with about 60 different types of stone, but says demand for British stones is still very small, apart from the occasional enquiry about jet. "Probably the only one we do get much demand for is jet, though many will settle for black onyx instead as it is less brittle," she explains. "We would mostly refer customers to specialist companies such as CW Sellors who cut and sell jet rather than try and supply it ourselves, partly because most of the enquiries are for something very specific that needs cutting and CW Sellors are able to do it."

Lanyon notes that demand for British stones - which also include Scottish Cairngiorm, sapphire, garnets, topaz and agates, among others - is naturally limited by supply. "I don't think that England really has enough good stones for the Britishness to be a useful selling point," she explains. "If you could say for sure that it is UK rough that you have had cut, people might be interested, but I suspect unless you were selling UK souvenirs or had some other pressing reason for selling British, people would not care where it came from. The main concern nowadays is whether it is from any conflict area, or areas where human rights and safety are not good."

Barker also notes that the British aspect of the stone largely appeals to locals associated with where the stones or minerals are found. "It's mainly people who live in the immediate area and who have family connections to the source, therefore in our case the British do thoroughly support British gemstones," he surmises.

With the growing interest in fine gemstones, Britain could certainly position itself as the go-to country for antique and fine gemstone buyers; the only weighty challenge now being to snatch the crown from other leading locations - namely Geneva and New York - to become synonymous with superior stone sales.

Looking Beyond A Gem's Beauty
Scientists use multiple tests to prove the region where gems were mined.
Inside Science
February 19, 2013
By Chris Gorski


Each precious stone carries within it clues that scientists can examine to prove the gem's original location. The diamonds, emeralds, rubies and sapphires in a jeweler's cases come in many colors, cuts and settings, but where a gem was mined is not apparent from its physical appearance.

From the startling blues in Brazil's Paraiba tourmalines and India's Kashmir sapphires, to the deep red of Myanmar's Mogok rubies, some regions are especially renowned for their precious stones. In turn, those gems gain cachet, and value.

Rubies and sapphires -- each a form of the mineral corundum -- both offer a considerable amount of visible variation. But that variation is not attributable to a country or region of origin. Scientists must rely on a battery of tests, including microscopic examination and laser-based chemical assessments in order to solve that riddle.

"Over time other deposits may be found in other parts of the world that are equal in beauty but still there's this cultural attachment to Burmese [Myanmar] ruby, Kashmir sapphire, Paraiba tourmaline, things like that that have traditionally been part of the early phases of building the enthusiasm and emotion of a particular material," said George Rossman, a geochemist at the California Institute of Technology in Pasadena, Calif.

Diamonds are beloved, but the verification of that gem's place of origin, or provenance, is often more difficult to address than the origin of other types of precious gems. Rossman said that laboratories have not yet developed "techniques that could work reliably on a single diamond." Governments and industry instituted a tracking system called the Kimberley process to protect against the transportations and sale of so-called "blood diamonds," stones mined in areas of political unrest whose sales help finance wars against legitimate governments.

As helpful as tracking can be, scientists can often discern a gem's origin only after subjecting it to various objective tests.

"Some deposits have compositions that are so unique, that you could pick those out with many techniques. But some of them are very, very similar to each other," said Nancy McMillan, a geochemist at New Mexico State University in Las Cruces.

Identification of the origin requires a large library of samples from all over the world; the job of collecting samples is never done, since new deposits and mines pop up regularly. Scientists examine the gems to gather information and in the future compare any gems of unknown origin against the library.

"We almost always start with a microscope because that gives us an idea of what kind of environment the gemstone formed in and whether it's magmatic origin or metamorphic origin," said Shane McClure, the director of identification services at the Gemological Institute of America laboratory in Carlsbad, Calif.

Along with looking at the gem under magnification, scientists rely on a number of other techniques to characterize it. They examine the little bits of other minerals captured inside a gem, called inclusions, the chemical variability within the gem, and its fluorescence -- how it shines under certain types of lasers or ultraviolet light.

The most advanced techniques examine the chemical makeup of the gem, element by element. Scientists use lasers to transform a miniscule amount of the gem into plasma, and then analyze the individual elements within the plasma. One of these methods is called laser ablation inductively coupled mass spectrometry, or ICPMS.

"This technology is extremely sensitive for trace elements; it's becoming one of the methods of choice for doing provenance studies," said Rossman.

However, McMillan, even though she allows that ICPMS "is the most accurate and most precise geochemical analytical tool known to mankind," favors a different technique, called laser induced breakdown spectroscopy, or LIBS. This technique also shines a laser at a sample, producing gas and a spectrum of light. Analyzing that spectrum provides a dizzying 14,000 pieces of information with each shot -- much more than ICPMS -- said McMillan.

"We've analyzed rubies and sapphires from, I think, 21 locations," said McMillan. "Using our method, we can tell at 95 percent assurance where a specimen is from, which is fantastic in my humble opinion."

McMillan also said she believes that LIBS can be used to identify the provenance of diamonds, although much work remains to prove that the technique works sufficiently well.

Rossman said that he uses both instruments, but finds ICPMS "more versatile," especially when the concentration of certain elements is very low. McClure said that LIBS can be too destructive of the sample gem. Both methods can detect minute amounts of elements within a sample.

In 2003, some sapphires on the market that had been treated with beryllium in order to change their color, said McClure. He said that ICPMS can detect that element at levels of about .02 parts per million in sapphires, and is much better equipped than LIBS to address this type of issue.

Despite the many sophisticated techniques at scientists' disposal, the provenance of some gem specimens can be difficult to identify, said McClure.

"Our end goal is to protect the public and what the public buys in the gemstone industry," said McClure. "We take that responsibility very seriously."
 


Gem Prices Overview

Like the stock market, gems keep rising on lower volume compared to year's past. We are increasing our Gemstone Price Trends (see page 7) for all gems unheated or not treated from Burma. That includes Burma ruby, Burma sapphire and Burma spinel. Prices are insane for these goods in Burma. Dealers either buy or go home empty handed. A large Japanese buyer may be trying to corner this market. Also, Asian, European and American collectors cannot get enough of these stones. Untreated Colombian emeralds keep climbing to new highs.

White diamonds declined for the first time since the beginning of the financial crisis. The dollar, precious metals and diamonds are inexorably linked. Due to new auction records and decreasing supply, we are increasing our Fancy intense Pink Diamond Chart.

Finally, Tanzanite remains in a bear market.


Retail Gemstone Price Trends (1975-2012)

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Gem Robberies

Drag queens, fake beards and chocolates
Ivana Kottasova, CNN
February 20, 2013


Within eight minutes, a gang of eight men managed to snatch $50 million worth of diamonds from a plane on Brussels Airport on Tuesday.

"It comes as a big surprise that something like this is possible," said Jan Van der Cruysse, a spokesman for Brussels Airport.

"But of course, this is rather connected to banditism and organized crime rather than aviation security."

He is not the only official left stunned by robbers. From 1960s gangster film-style armed robberies to elaborate stunts involving drag queens and fake beards, thieves from around the world have tried almost anything to get hold of diamonds. Here are some of the biggest heists they pulled off: On Valentine's Day weekend in February 2003, $100 million worth of precious stones were snatched from the Antwerp Diamond Center. The thieves, headed by Leonardo Notarbartolo, reportedly managed to penetrate some of the most advanced security measures, including hi-tech combination locks, motion and heat sensors -- and 18-inch steel doors. The gangsters even changed the tapes of the security cameras in the building to avoid being identified. They did, however, make one mistake: they left behind a half-eaten sandwich with DNA samples on it. They were arrested after months-long police operation involving detectives in several countries. The jewels were never recovered.

The sensational robbery inspired a book "Flawless -- Inside the Largest Diamond heist in the History."

In March 2007, a man using the name Carlos Hector Flomenbaum adopted an unorthodox approach to robbery. Swapping weapons for chocolates and charm, Flomenbaum became a frequent customer at ABN Amro bank in Antwerp. Befriending the bank staff, who believed he was a successful diamond trader, he gained their trust and acquired a key to the bank's vault. Once he had the key, he simply let himself in and walked out of the front door with 120,000 carats of diamonds, worth $28 million. In mid-May 2008, four armed robbers -- two disguised as women -- walked into a jewelry store in Paris. Once inside, they pulled out their weapons, forced the customers and employees into a corner, and grabbed jewels out of display cases and safes. Swiping an estimated 80 million euros ($102 million) worth of jewels, the "drag queen robbery" became one of the biggest heists in history.

On New Year's Eve 2008, two armed men casually walked into a shop called Dialite Imports, one of New York's diamond district shops. Dressed in traditional Orthodox-jewish clothing accessorized with fake beards, they quickly gained access to the store's safe, spray-painting two security cameras in the process. They disappeared with $4 million in diamonds and other jewels. The heist later turned out to be an elaborate inside job set up by the store's co-owners, who were $1 million in debt, six months behind on their rent and acquired a new insurance policy shortly before the robbery.

In 2009, two sharp-suited men walked into Graff Jewellers on central London's New Bond Street. In the middle of the afternoon, with people walking on the streets outside, they threatened employees with handguns and managed to steal 43 items, with a value of about £40 million ($65 million).

In 1994 three men armed with a machine gun stormed into the Carlton Hotel in Cannes, France. They stole jewels valued at £30 million ($43 million) from a jewelry shop in the hotel. Reportedly, the rounds they had been firing were blanks -- which did not prevent them from gaining the world's biggest gems robbery record in Guinness Book of Records.