|Vol. 24, No. 1
On February 17, 2006 in St. Moritz, Switzerland, a 8.62 carat Burma ruby sold
for $3.62 million at Christie's "Important Jewels". This set a new world record
price for an unheated Burma ruby at $420,000 per carat. Previously, the world
record was the April, 2005 Christie¢s New York sale of the 8.01 carat oval cut
Burmese ruby. It sold for $2,200,000 to an Asian private or $274,656 per carat.
See The Gemstone Forecaster, VOL. 23, #2, Summer, 2005.
The 8.62 cushion cut Burmese ruby ring by Bulgari was the top lot at Christie's auction. Dubbed "The Graff Ruby," it was purchased by famous jeweler Laurence Graff. Graff is usually a major player in the colored diamond market. Graff's fortune is approximately US$1.3 billion, slightly below that of rock star Paul McCartney. "This is the finest ruby I have ever seen, and I am delighted to own it," Graff said in a statement. Graff said he might set it in a new ring for a client.
This new record probably means either the 8.62 is 50% better than the 8.01 or the Burmese gemstone market has increased over 50% in less than one years time. Let¢s try and analyze the 8.62 and the 8.01 to see if the 8.62 is superior.
One of the most misused terms in gemological terminology is the term pigeon¢s blood. Christie¢s used this term in describing the 8.01 last year. Based upon the AGL grading report, the stone was NOT pigeon¢s blood. Nevertheless, the catalog said the 8.62 is remarkable for its combination of attributes: £pigeon¢s blood§ red color, superb transparency and absence of any signs of heat treatment.
Regretfully, the ruby was certified by the SSEF lab in Switzerland with the statement "No indications of heating". It is impossible to accurately compare the 8.62 with the 8.01 which was AGL graded last year. With these two widely different grading reports, it is like trying to compare apples and oranges. The SSEF report gives us no clues regarding color, tone, clarity, brilliancy, finish or proportions.
What we do know from the 8.01 AGL grading report, is the stone was not pigeon¢s blood, at 65% red, and was free of inclusions. You could make a case that if the 8.62 was free of inclusions and was 70% red, the price difference would be understandable.
We can only speculate from the photos about the 8.62. It is practically impossible to accurately gauge minute differences in color across computer monitors. However, in my humble opinion, this stone is not 70% red or pigeon¢s blood red. The 8.62 appears to have large pink and purple secondary colors. It would be my guess the stone is as red as the 8.01 but probably only 65% red.
The other issue that bothers me is the stone looks really spready, which means the stone has low brilliancy. The 8.01 had 75% depth and 80% brilliancy, which I would prefer to own over the 8.62. If we assume the stones are about equal, we are left with the conclusion the unheated Burma ruby market is increasing dramatically in price. This is true based upon my contacts that travel in and out of Burma and the new prices at the Tucson Gem Show. Of course, all this assumes an efficient market where prices are logical. Perhaps Graff simply got caught up in an auction bidding war and he wanted the stone at any price.
Whatever the reason behind the new record, it is obvious large unheated Burma rubies are rare and the world is finally recognizing this fact. These new prices will filter down to all sizes. The more you have of these stones, the better off your portfolio will be.
Prices and Attendance Up But Dealers Grumble
by Robert Genis
The Tucson Gem Shows are considered the mecca of the gem world. Once a year almost everyone in the colored gemstone business makes the annual trek to Tucson. However, after years of expanding, one wonders if the Tucson shows mindless growth is wearing, not only on the buyers, but the sellers too. Although the AGTA stated attendance increased, many dealers question these numbers. The shows appeared active but actual real buying was scarce. Many come to Tucson to get stones on memo and no one really knows what the true sales are until months later.
According to Jerry Romanella of Commercial Mineral, Scottsdale, Arizona, £We did about the same as last year. I believe most people did worse but we have a diverse inventory and sell numerous types of stones at all price points to many people. We are not like a lot of big dealers who need to make large sales to make the show successful.§
Romanella has a theory about the Tucson Gem Shows. He contends the show is evolving because the independent stores are visiting the show less and less as time goes by. They are so busy selling they do not have time to take a week off to get to Tucson. Romanella states, £It really doesn¢t make sense for them to come to Tucson to buy less than $25,000 in loose stones. It is much easier to buy branded gemstones or designer jewelry. If they need something else, they will call us during the year and we will memo it to them. The wholesale colored stone business is turning into a memo business instead of a selling business.§ Romanella concludes, £Although the attendance may be up at these shows, it is basically the same people who have been coming for 20 years. It is simple economics that if the buying pot is approximately equal and the number of vendors are increasing, each vendor will get less. This is the economic reality of the show. There are way too many shows, at over 30 now in Tucson.§
A major dealer in fine goods stated, £The shows were not on fire. The amount of US retail brick and motor jewelry store attendance was way down. We saw fewer and fewer faces we knew from years past. I don¢t know how the shows count attendance but real buyers are declining not increasing.§
The New York dealer sold most of his goods to overseas people. He said, £I sold to Europeans and Russians. Except for a few large sales, the vast majority of sales were in the under $3000 range. Buying was very specific. People had lists that were created from their client base. They would see the stones their clients wanted and call them from the show on their cell phones. Many buyers took copious notes and then would visit similar dealers. Some returned and others did not. One trend I noticed was many buyers were looking for goods that were not realistic. Gem prices have moved and many seemed almost unaware of these new pricing realities.§
The New York dealer finishes, £The problem with the gem market is 96-97% of our business is now memo. Very few people buy goods anymore. We have become bankers for other dealers and the retailers. The only way to succeed in this business is to have the right goods at the right price at the right time. That is a very difficult challenge.§
Anne Barker, Manager of Commercial Sales, Barker and Company Scottsdale Arizona stated, £We were happy with the show. Although we haven¢t tabulated up our sales yet, we believe our sales were a little bit higher than last year. Traffic was definitely down from last year. We approach Tucson with a twofold sales strategy. We sell in volume to manufacturers and we sell single stones to retail jewelers. This year we sold a mix to both groups. However, we buy by the kilo so we really don¢t want to sell by the carat. We always sell Arizona Peridot to Japanese and Taiwan dealers. We also sold rubellite, peridot and demantoid to Europeans.§
Hot New Stone
The stone everyone was talking about but few saw was the new Mozambique Paraiba. Some material was at the show in large sizes. It was described as looking exactly like the old Brazilian material by some, but by others as not as intense or electric blue as the Brazilian material. The Germans might be players with this material. Preliminary reports say the material is heated but this is a dangerous proposition because most of the goods break, explode or crack under pressure. The amount of production comes in drips and drabs. These goods need to get to the laboratories before they are safely offered to the public.
Burma Goods and Pricing
The amount of unheated Burma ruby, sapphire and spinel was down dramatically from years past. What was there was dramatically higher in price. Many spinels, not even gem red, were $1500 per carat for carat sized stones. A major Eastern European buyer spent all of last year in Burma buying whatever he could at very high prices. Some of these goods were displayed at the show but even they were sparse. The problem the old time Burma dealers are having now is the Burmese now consider these prices the new price levels of their goods. In essence, they say to the old dealers, £Why should I sell to you at a low price when the European will soon return and pay a higher price?§ This has not only driven up the prices but made it almost impossible for the old time dealers to buy. If they pay these new high prices, they meet buyer resistance in the United States. This is why there are so many calls for goods that cannot be met. Wholesalers and retailers must educate their buyers on the new prices.
Top quality emerald prices are also up in price because of the devaluation of Colombian currency and the fact production has been dismal of late. What everyone wants are non-treated clean Colombian emeralds. Of course, these are rare to begin with but collectors are constantly searching for these goods. Tanzanite was also slightly up in price.
A Diamond Speculator
Very few diamond dealers attend the Tucson Gem Show. A dealer who wished to remain anonymous said he remembered the last time gold and diamonds started rising in value. The next product to increase was colored gemstones. He was at the show speculating by buying unheated Burma goods even though he had no customers for the stones. £My clients don¢t want to know anything about color.§ They have no trouble paying me $50,000 for a diamond but when I ask for $20,000 for a ruby, they get scared.§ Despite that fact, he would rather keep a portion of his inventory in fine colored gemstones rather than diamonds. He stated, £Let¢s face reality. A 5 carat E-VVS1 is not rare compared to a gem red unheated Mogok ruby.§
Many dealers are fed up with the city of Tucson and state they are now going to move their main selling operations to Las Vegas. Complaints were heard about the outrageous parking fees, the weights and measure compliant officers, police ticketing buyers, the general rising of prices at hotel and restaurants. Others blamed the show promoters as greedy with negative attitudes. Maybe if the entire show could be placed under one tent it would make more sense. Others said Tucson really is turning into a retail show and the prices reflect this reality. One famous gem observer said, £I see this year as the beginning of the end.§ Only time will tell if this sentiment is the result of three weeks of mental and physical exhaustion or the new trend.
Color Change Diaspore Hits the Market
Brand marketed as Zultanite
By Robert Genis
Zultanite is a relatively new gemstone hitting the international market. Actually the gemstone is diaspore and is found in a remote, mountainous region in Anatolia, Turkey. Gem-quality crystals were first discovered there in the early 1980s, but never mined commercially until Zultanite Gems LLC obtained the deposit. What is unique about this gem is that it changes color based upon the lighting source.
What is in a name?
Most people in the trade think of diaspore as an unfacetable low end stone. As a matter of fact, it wasn¢t until the late 1970¢s that any diaspore had ever been faceted. The name Diaspore conjures images of a sea creature or possibly a sedative. Obviously, the owners of this mine think the name is not sexy. For marketing purposes, they choose Zultanite to honor the 36 sultans who founded the Ottoman Empire in Anatolia in the late 13th century. According to Murat Akgun, Partner, Zultanite Gems LLC, Ft Lauderdale, Florida, £Diaspore has had a reputation of being inexpensive. What¢s out there now are stones uncovered by independent miners looking to turn a fast dollar. The stones are poor quality, very included, and cut in China or Thailand in ways that do not capture the color change. We hope this material will disappear from the market within the next year.§
Bringing this stone to market was a difficult venture. Akgun states, £I kind of fell into this project. I was a jeweler/gem dealer that traveled often to the United States. The original owner of the mine approached me as an investor. I believed in the gemstone and invested over $100,000 in the project. However, after time, I began to realize what the owner was telling me didn¢t add up. I had no reason to doubt him because he was from a good family. However, the bottom line was he was a crook. He was dealing in these stones but had no legal Turkish right to do so. Therefore, I found a partner and spent the time and the money to legally acquire the mining rights to these gemstones. The government of Turkey owns all the land but we have acquired the proper licenses and permits.§
The Zultanite mine can only be described as low tech. It is 7 miles away from the closest village and is at an altitude of 4000+ feet. They have no electricity or water. The basic method of mining is chisels and pick axes. There is only one bad road to the gem area. The entire gem area encompasses 20,000 acres and Zultanite Gems is having problems securing the perimeter. Local villages poach gems at night. The company is preparing for steady production, £Our engineers are planning a mining strategy, and the mine should begin producing regularly by early 2006. Although we¢re not able to confirm reserve figures, supplies seem promising,§ concludes Akgun.
Zultanite is 6.5-7 on the Mohs hardness scale, has a refractive index of 1.702-1.750. It is a member of the mineral family diaspore, a hydrated aluminum oxide plus manganese. It is found in colorless, light pink, yellow, green, brown, or light to dark red. Zultanite is typically eye-clean with some inclusions under magnification.
The most interesting characteristic of this gem lies in its color changing under different lighting conditions. Its main attribute is you can easily see the 100% change. You don¢t have to use your imagination like so many color change stones. This is unusual because usually the best color changes occur with dark tones and this material possesses light tones. The color changes are dramatic and obvious. Also, the larger the stones, the better the color change. According to Akgun, £In the best cases, Zultanite transforms from a kiwi green to a rhodolite purplish-pink.§ According to my observations of a sample of these stones, the stone washes out in direct sunlight. However, under durotest light, or in the shade, the stone looks like green tourmaline or light Peridot. Under incandescent light, the stone changes to an almost olive color or greenish brown. The Zultanite owners like to call these colors brownishpink, or pinkish-champagne or ginger colors. Sometimes, I observed pinkish flashes off the stone but they look almost purple in dark restaurant lighting at night.
Zultanite¢s perfect cleavage also makes it very difficult to cut. £It¢s easy for the gem to cleave or split apart in one direction,§ contends Akgun, £the cutter has to orient the rough correctly to minimize this tendency. Moreover, the cutter must position the gem¢s angles to evoke the full color change inherent in Zultanite.§ Combine this with Zultanite¢s low yield, translating to 90% of the rough lost in the cutting process. Presently, the Turkish mining company is using AGTA award winning cutters to fashion the material.
These stones are cut in a myriad of shapes. They have fancy shapes such as shields, pears and marquise and standard shapes such as rounds, ovals, and cushions.
The average size range available from Zultanite Gems is 3- 5 carats. Any Zultanite over 5 carats is rare. They currently only have 10 stones that are over 10 carats.
At press time, Zultanite Gems have not decided on a pricing structure for the gemstones. They are trying to find a happy medium where according Akgun, £The gems cannot be priced too high nor too low.§ The gemstones really cannot command the price premium of alexandrite. They probably need to compete with color change sapphire, color change garnet, and color change spinel. Possibly even an andalusite, which is known in the trade as poor man's alexandrite.
Due to the limited quantity of the new material, the main market for these goods are custom designers and small manufacturers. It is hard to mass market any product when their entire inventory is only 400-500 gemstones. The more obvious market is for collectors. Here is a very rare stone with unusual characteristics that may excite certain factions in the collecting market.
Most colored gemstone collectors prefer red, blue, and green colored gemstones. However, given the success of orange spessartite garnet recently this may be changing. In the colored gem world, the two ugly duckling colors remain brown and gray. Now you have a stone that is predominately brown in one part of its color change. Of course, diamond companies have always marketed brown or champagne diamonds to men as a masculine color. Zultanite should learn something from the diamond dealers. Whether this stone becomes the hot new stone or not, it will be interesting to watch its progress.
£The irony is that, because fashion is tilting toward brightly colored stones right now, these one-time B-list gems are getting more buzz than diamonds in some circles. But what's really driving the move to semiprecious stones is rising costs for other materials. Prices of rough diamonds have risen as much as 40 percent over the past two years, due to a change in the way De Beers distributes them, with large diamonds seeing the biggest increases, says Martin Rapaport, who publishes a report that people in the industry use to set prices. A slightly better-than-average one-carat diamond now goes for $9,440, he says. And the price of gold has surged to more than $500 an ounce, rising 18 percent last year; it's now near a 25-year high§
Not-So-Precious Stones Cost Big Bucks
By Cheryl Lu-Lien Tan
The Wall Street Journal
£Red stands for passion, green is for envy, yellow is for cowards or lust. You can see red, feel blue and be in a black mood.
Every woman loves a diamond but the interesting ones prefer colour in their gems. What kind of woman loves a ruby or sapphire? Is she the same girl who would wear green suede boots instead of black, and a purple satin blouse instead of a sensible white cotton shirt?§
Look On The Bright Side to Survive Grey Winter Days
2/7/06 IC Wales. Co. UK
In The News
By Thomson Dialog
Financial Times Information Limited
Diamonds: It is said that Alexander the Great found a valley full of both diamonds and poisonous snakes. No one could work out how to retrieve the jewels until Alexander had the idea of throwing down raw meat, to which the diamonds attached. When eagles flew down for the meat, Alexander's men just had to follow them to their nests.
It sounds like fantasy but diamonds are attracted to fat, and the story reminded people how to tell real diamonds from fakes. De Beers still practise Alexander's trick in their South Africa mines today: They use "grease tables" and only the valuable stones stick.
Today, most engagement rings are diamond but after the war, people wanted holidays, cars or colourful gems to celebrate a future marriage. In 1947 a New York copywriter, given the task of finding a slogan for her client's product, stayed late in the office. "I put my head down and said: 'Please God, send me a line.'" Then she scribbled: "A Diamond is Forever" and the market for the gem was never the same again.
Amber: In the 13th century people were killed for it and in the 20th century the Jurassic Park series of films was built on the notion that dinosaur DNA could be preserved in it. Amber is an ancient fossilised resin found most famously along the Baltic coast, where it has bubbled up from an underwater amber forest.
It has been used in jewellery since prehistoric times and, while most amber is yellowy-orange, it can be cloudy white, or even green and blue.
Amber is always more than a million years old while most amber is 40 million years old which means that the Jurassic Park dream is unlikely because dinosaurs lived about 170 million years ago.
In the Middle Ages, peasants in Poland would be hanged without trial for carrying amber. Before then, amber was thought to be lucky.
The Amber Room is the most famous amber object a set of wall panels designed by Prussian kings in the early 18th century and improved by Russian empresses 50 years later.
It was last seen in Prussia's Konigsburg Castle in 1944. For years this expensive piece of interior design was thought hidden in caves or vaults and people were said to have been murdered for it. However a recent theory is that it was lost in a fire in 1945. It must have made a wonderfully scented blaze.
If you rub amber hard it attracts bits of lint and paper to it, and sometimes makes sparks. So it is not surprising that when electricity was first discovered it was named after "elektron", Greek for amber.
Emerald: When Carroll Chatham was 15 he blew out the windows of his neighbours' house in San Francisco in an attempt to make diamonds. "Get another hobby, " said his father angrily.
So he did and, by the time he was 21, in 1939, he had made his first synthetic emerald. It was the first time such flawless emeralds had ever been seen in such numbers. When he took his inventions to a New York store the manager was convinced they were stolen and called the police.
In the ancient world emeralds came from mines in southern Egypt. But the greatest emeralds are from Colombian mines. They are dangerous places, with frequent kidnappings. "How good are you with a gun?" asked one American emerald dealer about a proposed visit to the Colombian mines. "Because you'll probably need at least two." Almost all natural emeralds today are treated with either polymers or oil to reduce the cracks and shapes inside them called "jardin" because they look like a garden. The treatment is so common that it is rarely even acknowledged.
Emeralds are more fragile than sapphires, diamonds and rubies and break more frequently.
Jet: When Prince Albert died in 1867, Queen Victoria went into mourning for nearly 40 years and the fortunes of a small town in Yorkshire turned. No one mourning in Victorian England was allowed to wear coloured stones; widows were never allowed to wear them again.
So, following the Queen's example most women turned to the only black gemstone they knew: jet, from the North Yorkshire coastal town of Whitby. It is the fossil of 170 million year-old trees, ancestors of today's monkey puzzles. Jet was so popular that it led to many fakes. "French jet" is glass; "bastard jet" is either vulcanite a form of plastic or coal. Spanish jet is the real thing but from Galicia and it is softer than the Yorkshire variety.
You can test by scratching it against the back of a tile. Glass leaves a white mark; coal leaves a black. Real Whitby jet leaves an earthy brown line, although the makers of Victorian vulcanite jet soon caught on and added a brown dye to their mix.
Incidentally, Queen Victoria did not stick rigidly to her own rules and was occasionally seen with a diamond and sapphire tiara that Albert had designed for her which sat jauntily over her widow's bonnet.
Sapphire: We usually think of sapphires being blue but in fact they can be green, violet, black, yellow, white or pink as well. They can never be red because red sapphires are rubies.
The best sapphires came from Kashmir. They were discovered by accident in 1880. For the next decade the remote mountainside was torn apart. Just as suddenly the seam finished and nothing as beautiful has ever been found again.
The main source of sapphires Sri Lanka became famous in a story of Sinbad the sailor, who was shipwrecked on an island and saved himself by taking a raft along a river lined with precious stones. That river really exists, carrying sapphires in its flow. Today many sapphires are heat-treated, where they are put into special ovens after which they emerge purer, lighter, and brighter. If you buy one, you should always ask about treatments.
Ruby: Last month, an 8-carat flawless ruby, whose new owner, Lawrence Graff, named it after himself, was bought at Christie's for $2.05 million a record $242,000,000 per carat, almost twice the previous record and three times the highest price paid at auction for a colourless diamond. The gem came from the same source as all the greatest rubies: the Mogok Hills of central Burma.
The most famous "ruby" here is in fact a spinel: A softer and more purplish stone. It is called the Black Prince Ruby and is said to have been given to Edward The Black Prince in 1367 by a grateful King Don Pedro of Castille who had murdered the King of Granada for it (and his throne). Other theories suggest it became part of the Crown Jewels in the 17th century as a replacement for the gems destroyed during the Civil War.
Opal: There was a stone in the crown of the Holy Roman emperors said to be the colour of pure white snow, sparkling with splashes of red wine, and with the ability to shine in the night. It came from the Czernowitza mines in Slovakia, as did another famous opal belonging to the Roman senator Nonius, who valued it so highly that when Mark Antony requisitioned it he refused, even though he knew his punishment would surely be exile. Most opal comes from Australia.
When Queen Victoria learned that deposits had been found in her colony she commissioned many pieces of jewellery made out of it. It was one of her favourite stones.
Some people don't like opals because they have seen only "doublets" or "triplets", which are legal ways of selling small opal chips by mounting them on less precious minerals. But there's also a superstition that dates from the 19th century that says they are unlucky. Sir Walter Scott wrote a ghost story about Baroness Hermione, who died dramatically when a drop of holy water splashed accidentally against her opal. Queen Alexandra, wife of Edward VII, went along with this belief and removed "the unlucky opals" from the late Queen Victoria's collection.
In earlier times, however, these jewels were thought to be positively brimming with luck. The Goths believed they were forged from the eyes of heaven, and 10th-century Arabic scholars wrote that people wearing opals would enjoy great fortune and good health.
Pearls: One of the main reasons for Julius Caesar's attempted invasion of Britain in 55 BC was to get hold of our pearls. Scotland and Cumbria were said to have the best pearl rivers in the world. Caesar craved them, partly because they were beautiful and partly because, as the gems of Venus, goddess of love, they were very good as chat-up presents for women he liked. People fished for Caesar's favourite pearls in Scotland until 1998, when it became illegal. Traditional pearl fishers were travelling people who lived in tents and had their own special language.
Cleopatra also fancied pearls and once had a bet with her lover Mark Antony about who could give the most expensive dinner party. He went first and was astonishingly lavish. She spent less on food but at the end she took off her pearl earrings and swallowed one, which instantly gave her banquet the value of a small Roman province.
Today we almost never see natural pearls such as Caesar's or Cleopatra's. Less than one in a million round pearls sold today is natural, while the rest are created on sea farms all over the world.
Today's so-called "pearl divers" are mostly not diving for pearls at all but for large live oysters, in which the best pearls can be cultivated. It is a harsh business.
Beads are forced into the creature's sexual organs to enable the production of pearls. Half die of shock, which is why many vegetarian organisations recommend their members don't wear pearls.
The Daily Journal
Emerald King in Coma After Shooting
The man regarded as the king of Colombia¢s lucrative emerald trade lies in a coma with his life in the balance after being shot last weekend, El Tiempo reported. The attack against Yesid Nieto, 35, had been kept quiet for several days. El Tiempo said that Nieto was shot in the head and chest by several assailants who burst into his Bogot¬á apartment. Though the businessman has his own, government-approved security establishment that includes 30 armed bodyguards, he was practically alone at the time of the assault, the paper said. Nieto is the spokesman for the seven powerful clans that control 80 percent of emerald exports from Colombia, the world¢s leading producer of the gem. The merchant remains in the intensive care unit at Clinica Reina Sof¬ía, a private hospital in the capital, according to El Tiempo, which said that doctors are unsure if Nieto will survive. The daily cited analysts who said the attack on Nieto could spark a renewal of the war between the emerald clans that claimed more than 20,000 lives before a truce was reached in the early 1990s. Some observers suggested that the shooting may have been linked to Nieto¢s offer to help authorities in their effort to eradicate 6,000 hectares (14,800 acres) of coca leaf the source of cocaine belonging to right-wing militias active in the emerald-producing region. The consortium led by Nieto exports some $50 million worth of gems annually, and El Tiempo reports that the emerald king has diversified his holdings with the acquisition of cattle ranches, gas stations and beverage distributorships, among other enterprises.
Identifying Gems and Minerals on Earth and Mars
University of Arizona
It'll be a snap to identify gemstones once Robert Downs finishes his library of spectral fingerprints for all the Earth's minerals. Downs is almost halfway there. So far, the associate professor of geosciences at The University of Arizona in Tucson has cataloged about 1,500 of the approximately 4,000 known minerals using a technique called Raman spectroscopy. The effort is known as the RRUFF Project.
"We're developing a tricorder," Downs said, referring to the instrument used on the "Star Trek" television show that could be waved over materials to identify their chemical composition. Downs' work is destined for space. Although Downs' current Raman spectrometer takes up an area the size of a tabletop, his colleague M. Bonner Denton, a UA professor of chemistry and of geosciences, is developing a pocket-sized Raman spectrometer to be used on the 2009 Mars rover.
Downs is collaborating with George Rossman of the California Institute of Technology in Pasadena to develop the database of minerals. The technology being developed for Mars will help create handheld instruments for use on Earth. One use for a hand-held instrument would be the identification of gemstones. Downs and Denton will both give presentations on that aspect of the project on Sunday afternoon, March 12, at the 57th Annual Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy (PITTCON 2006).
Other ways to accurately identify minerals, such as X-ray diffraction and electron microprobe, require grinding a bit of the sample to powder or polishing the sample in a specific manner. However, such rough treatment may not be the method of choice to determine that a glittering gemstone is truly a diamond, rather than just a piece of cubic zirconia. Unlike other methods of identifying minerals, a Raman spectrometer does not require destructive sampling. It shoots a laser beam at the sample. The laser excites atoms within the sample, which then emit a very weak light of a wavelength in a pattern characteristic of the material. "It's like a fingerprint," Downs said.
The technique is named after Sir C.V. Raman, who won a 1930 Nobel Prize for figuring out the underlying physics. But no Raman spectrometer, big or small, can conclusively identify Mars rocks or any other kinds of minerals without the kind of comprehensive database Downs is creating. When an unknown material is analyzed with a Raman spectrometer, it can be identified by comparing it with reference information from a database.
In Downs' lab, a small army of undergraduate researchers is helping complete the RRUFF Project, the first comprehensive database containing the Raman spectra of all the Earth's minerals. The RRUFF project is supported by funding from gemstone connoisseur and collector Michael Scott, founding president of Apple Computer. Scott has a degree in physics from the California Institute of Technology. RRUFF is the name of Scott's cat.
NASA provided funding to develop the instrument for the 2009 Mars Rover.
Gemstone Price Trends (1975-2005)
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