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"The Diamond Deception"

PBS Airdate: February 1, 2000
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H. TRACY HALL, SR.: We can take some of this material and put it in this tube which is constructed out of graphite. And we will be heating this in a high-pressure, high-temperature press. And in the process, the peanut butter will be carbonized.

NARRATOR: Cooking peanut butter at temperatures of 3000 degrees under pressure of over a million pounds per square inch is a recipe that won't fill your stomach - but it might make you rich.

H. TRACY HALL, SR.: So, peanut butter to diamond.

NARRATOR: For nearly 50 years, scientists have known how to transform carbon rich substances into small industrial diamonds, but the trick to making gem quality stones has remained elusive - until now. Today, it may be possible to manufacture diamond jewels that are indistinguishable from the real thing - and it has the diamond industry worried.

MARTIN RAPAPORT: Just what if there is a way to synthesize diamonds that are non-detectable from natural diamonds? What if technology gives us the ability to make a synthetic diamond that no one knows is a synthetic?

NARRATOR: What will happen to the mystique of this billion-year-old stone if science finally solves the mystery of making the perfect gem diamond? For this most brilliant and treasured jewel, Mother Nature, it seems, no longer holds the patent.

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NARRATOR: Deep under the earth - in mines scattered around the world - thousands of tons of rock are displaced each day in hopes of uncovering a few gem-quality diamonds.

STEPHEN LUSSIER: There's something magical about diamonds, they've captured the imagination of people for so long, I think it's things like, you know, the fact that they are three billion years old, the fact that it takes enormous effort to find diamonds in the world. It takes even more enormous effort to get them out. They have this magnificent way of dealing with light that separates them from all the other precious stones. They really are just a miracle of nature.

NARRATOR: But how would we feel if this miracle of nature could be copied, atom by atom, in a laboratory in just a few hours? Could any reproduction, no matter how faithful, ever compare with a natural stone?

ALEX GRIZENKO: A diamond is a diamond. If it's carbon and if it looks like a diamond, it's a diamond. It's not a simulant. And as we know, there are many simulants on the market. Cubic zirconia has been around for many years. A new simulant called moissanite has entered the marketplace. But these are all pretending to be carbon. They're not carbon. Hence, they're not diamonds.

NARRATOR: Diamonds have always invited fakery, which was often easy to spot. And while the techniques for producing look-a-likes have improved, these sparklers are still no closer to being diamonds than a piece of glass. Real diamonds are much more difficult to make - and nearly impossible to break. Their chemical composition was only discovered in the late 1700s, after pioneering chemist Antoine Lavoisier found a way to burn one. In this lab a real diamond is being heated to over 1500 degrees centigrade. After being dropped into liquid oxygen, the diamond burns completely. All that is left is carbon dioxide gas - proving that diamonds are nothing but pure carbon. The only pure carbon substance known in Lavoisier's time was graphite - the soft, black material in pencil lead.

ROBERT HAZEN: You see, these structures couldn't be more different. You have graphite, which is a beautifully layered structure. It has layers of carbon atoms separated by very weak bonds. Now, within the layers, each carbon atom is beautifully co-ordinated to three other carbons and that leads to very strong layers. But the bonding between the layers are exceptionally weak. By contrast, diamond, the hardest material known. And it's hard because of the way it's bonded together. This three-dimensional linkage in which every carbon atom is surrounded by four neighbors, and it forms a complete three-dimensional structure like a trestle bridge - an incredibly strong structure. You see the beautiful three-dimensional symmetry when you look in one direction and you see - just rotate the structure slightly, and you get that four-dimensional symmetry. And it's the interaction of these symmetry elements that gives diamonds its strength. You know, a structure can only be as strong as its weakest direction, and in diamonds there are no weak directions. Every bond is almost as strong as a bond can be.

NARRATOR: Could slippery, soft graphite be transformed into diamond - the hardest and most brilliant material on earth? For those who first dreamed of making diamonds, it must have seemed an insurmountable task. It was war that created the urgent need for manufactured diamonds. During the Second World War, diamond-tipped cutting tools were desperately needed to make weapons. Only diamonds were hard enough to cut and shape the tools required for making airplane parts, vehicle armor and other military hardware. At the time, American industry was dangerously dependent on South African diamonds. Fearing the loss of this critical supply, the American government was determined to develop an alternative source. But it would be another decade before one was found. In 1951 General Electric started project Superpressure. Its aim was to make the world's first industrial diamonds with the same properties as natural diamonds. A young chemist, Tracy Hall, was invited to join the team.

H. TRACY HALL, SR.: A person came in and announced that we had this big secret project, that we were going to try and make diamonds. And so hold up your hand, there's only one man we want. So I was the only one that held up my hand, so I got the job.

NARRATOR: Another member of the team was physicist Herbert Strong.

HERBERT STRONG: And he said, how would you fellows like to try to make diamonds? Huh? Yeah, sure. Very enthusiastic about it. No thought of failing at all, no, of course not.

NARRATOR: The first challenge was to find a way of transforming graphite into diamond. The team soon learned that graphite, despite its softness, is amazingly resistant to change.

ROBERT HAZEN: The bonding between the layers is weak so graphite flakes apart, but the bonding within the layers is incredibly strong because each carbon atom has four electrons that it wants to share with its adjacent atoms in covalent bonding. So in graphite there are three adjacent carbons to every individual carbon, sharing three electrons, and then the fourth electron resonates within these ring-like structures, adding additional strength to the graphite layer.

NARRATOR: The GE team first looked to nature when considering how to turn graphite into diamond. Because diamonds are found inside extinct volcanoes, embedded in a mineral called kimberlite, geologists believed they were formed in the molten ooze of the earth's mantle - more than 100 miles below the surface. Here, temperatures range between 2000 and 3000 degrees Fahrenheit. Pressures rise above one million pounds per square inch. Only in an environment of extreme heat and pressure, geologists realized, do carbon atoms coalesce into the highly compact crystalline form of diamond.

ROBERT HAZEN: It wasn't until the discovery of diamonds in their actual geological setting - the discovery of diamonds in the bedrock, the solid rock in which they occur, that it was realized that, gosh, these diamonds came from really deep in the earth - 100 miles down or more. And that discovery let people start thinking about pressure. And that was the key to diamond synthesis.

NARRATOR: By dating the minerals trapped inside diamonds, scientists learned that they were formed between 600 million and three billion years ago. But how long did it take nature to make a diamond? Did diamonds form slowly over millions of years? Or did they coalesce quickly - perhaps during their explosive race to the surface inside volcanic plumes of molten kimberlite? To find out, scientists would have to replicate the heat and pressure found within the earth's mantle. Only then might they be able to break down the atoms of graphite and see whether they would re-form as diamond. But the GE team had little idea what the right combination of temperature and pressure should be.

HERBERT STRONG: Just having a sense of how nature works, you realized it was going to have to be way up here at fairly high temperature - over a 1000 degrees centigrade, probably higher than that, that was a guess, and the pressure then would have to be up, for a diamond would be stable at that high temperature and wouldn't go back to graphite.

ROBERT HAZEN: So you had to get to the high enough temperature that the carbon atoms in graphite would be stripped apart from each other and then they could reform themselves as diamond.

NARRATOR: GE spent millions on diamond presses capable of focusing huge pressures and temperatures on the graphite capsule, but still the graphite wouldn't turn to diamond.

ROBERT HAZEN: Graphite at high temperatures and pressures remains graphite. You can go to tens of thousands, hundreds of thousands, perhaps even a million atmospheres pressure at room temperature. And the graphite will persist for a long time, because those carbon atoms are so tightly bonded to each other.

NARRATOR: After four years - and many broken presses - Project Superpressure was in trouble. The team had to find a way to make diamonds at lower temperatures and pressures or the project would be cancelled. But before they could make diamonds, the scientists had to figure out how to break down the atomic structure of graphite. They had one clue. Because diamonds are crystals - like ice - perhaps they, too, might be grown from a liquid.

HERBERT STRONG: What seemed logical to me was to dissolve the graphite into a solvent, so as to get the carbon atoms loose and make them available for forming diamond. Well, what is a solvent for carbon?

H. TRACY HALL, SR.: Well, I had read that some tiny diamonds had been found in the meteorite crater that was in Arizona.

NARRATOR: In the 1950s geologists discovered that a meteorite made this crater. Within it they found tiny diamonds that had been formed on impact.

SARA RUSSELL: When the asteroid hit the earth, it obviously must have been an explosion of tremendous energy. And we now think that this huge explosion actually provided high enough temperatures and pressures to form these diamonds.

NARRATOR: There was another clue in that meteorite - something they thought must have helped to form the diamonds. The diamonds were surrounded by metal.

SARA RUSSELL: I've got a piece of the meteorite here and you can see this dark colored inclusion here is mostly made up of tiny diamonds and it's surrounded by this metal that makes up most of the meteorite.

NARRATOR: It was the evidence the GE scientists were looking for. They hoped that a metal called troilite, when heated into a liquid, would act as a solvent to break the bonds between the carbon atoms in graphite - and do it at a pressure and temperature that was lower than the levels they had been using. They tried adding some troilite to the growth capsule.

H. TRACY HALL, SR.: It was a wintry day, it was cold but the sun was shining through the window, and I had put some troilite in this graphite tube, I put it in my belt apparatus. I turned up my heating system and I put the pressure on.

ARCHIVE FILM NARRATOR: The force builds up and up and up, eventually reaching nearly 500 tons, almost one million pounds per square inch. The outer surfaces reach 750 degrees Fahrenheit, inside 2600 degrees Fahrenheit.

NARRATOR: They hoped that the carbon atoms in the graphite would dissolve into the molten troilite, and then when they had reached a high enough temperature and pressure, would crystallize as diamond.

HERBERT STRONG: We were in the hunch stage - my hunch was that, when you're in the diamonds pressure region and you melt the metal, and these carbon atoms dissolve, then it turns out the metal says hey, I've got too much carbon in me here, I'm going to have to precipitate it out some way to get rid of it, and the way to do that is to precipitate it out in the form of diamond.

NARRATOR: They could only risk running their machine at full pressure for a few minutes. But they had no idea whether this would be enough for diamonds to form. Just as they had done dozens of times in the past five years, they broke open the capsule.

H. TRACY HALL, SR.: So I got down to the point where I picked things apart and got to look at what there's in the middle, and my eyes caught the gleam of the sun shining on these things, and I, you know, twirled it around a little bit and saw the sparkles, and at that instant I knew that man had finally turned graphite into diamond. My knees weakened, I had to sit down, I was overwhelmed.

HERBERT STRONG: Well, it was just a very nice feeling that we had a tough problem and we had solved it. We had been challenged and we met the challenge and faced it and won.

H. TRACY HALL, SR.: It was front page news in almost every newspaper in the United States, overseas too.

NARRATOR: Diamond making grew into a profitable business for GE. As the technology improved, so did the product. Today, nearly 90% of all diamonds used in industry are manufactured. But these tiny crystals would never be gems. GE was able to grow larger diamonds in the 1970s, but they cost more to produce than the price of natural diamonds. For the time being, the market in large, gem quality stones is dominated by a single player. De Beers is the diamond business, and controls the world diamond trade from this building in the heart of London. Over four billion dollars' worth of rough diamonds are sold here every year. An equal amount is kept on reserve. One of the ways De Beers has managed to keep the market value of diamonds high is by stockpiling some of its inventory. Many of the world's diamonds comes from DeBeers' own mines in Africa. But DeBeers has also formed strong partnerships with many other mining companies around the world. And when new sources of diamonds are discovered - in places like Siberia and most recently in Canada - De Beers moves in. Their goal is to protect the value of diamonds by controlling their release. It's impossible to know how much time and money is spent in search of diamonds, but it's clear that the amount of effort it takes to produce even a single engagement ring is impressive. It is estimated that for every one of these rough stones, 250 tons of rock must be mined and processed. By weight, that's a ratio of more than a billion to one. This is what rough diamonds look like, fresh from the ground. They are sent to De Beers in London where they are sorted according to size, shape and color. Inspectors examine each stone, noting the number and size of inclusions, tiny mineral deposits trapped in the diamond crystal at the time it was formed. Dealers around the world then transform these rough stones into gems. Most diamonds are cut before they are shaped. It is an operation that requires careful attention to the stone's grain and internal crystal formations. A diamond can be cut using a diamond-edged saw, a laser beam, or by hand, in the traditional method called cleaving. Once cut, the stone is then roughly shaped, using another diamond to grind it down. Facets are formed and polished by pressing the diamond against a spinning iron disk covered in a paste of diamond dust and oil. It is not uncommon for more than 50% of the original stone to be lost during cutting. The facets on the diamond must be fine tuned in order to maximize the color and quality of light that is reflected from the surface. One mistake by any of the cutters can destroy the value of a stone. But when everything works, the results are spellbinding. The tradition of wearing diamonds began in ancient times. But for centuries, they belonged only to the rich and the royal. One of the most famous - the pale blue Hope diamond - was the favorite jewel of King Louis XIV. Not until the 20th century, following the discovery of rich deposits in South Africa, did diamonds become more widely available. But more than price, it was promotion that made them the most popular gem in the world. And Hollywood played a leading role. By 1953, the year Gentlemen Prefer Blondes was released, diamonds were more than a girl's best friend. They were big business. It was this kind of exposure that helped propel the diamond trade into a multi-billion dollar industry that shows little sign of abating. As the demand for diamonds goes up, so do the incentives for any would-be diamond makers hoping to cash in on the market. In post-Soviet Russia, scientists and entrepreneurs desperate for a foothold in the world economy are racing to create the perfect gem-quality stone. One of them, Boris Feigelson, set up his own lab in rooms rented from the Institute of the Blind. His plan was to grow large gems from a tiny seed diamond. But this required expensive high-pressure equipment, and with little money, everything he used had to be built from scratch. To make big stones, Feigelson knew he would have to run his presses for days at a time. It was a risky proposition.

BORIS FEIGELSON [voice over translation]: We had to select the right materials and the right parts for the press, because if it was set up wrongly then it was quite possible that there would be an explosion. Everything would come flying out at high pressure.

NARRATOR: Feigelson tried repeatedly to redesign his presses to withstand higher pressures without breaking. Finally in 1995, the presses could run for the days needed to produce larger gem quality crystals. But the real science of diamond making is in the delicate chemistry of the growth cell itself. It is here that Feigelson focused his attention. At one end of the growth cell Feigelson planted a grit seed of tiny diamond. Above the seed is the metal solvent and then the graphite source. Heat at the top causes the carbon atoms to filter out of the metal solvent to the cooler temperatures at the bottom where they latch onto the seed. If the process is regulated carefully, the seed grows. After two days of high temperature and pressure, these machines can each produce a one-carat diamond - large, but flawed, with telltale signs of manufacture. Much would need to be done to reduce the processing time and to improve the quality of the crystal. Boris Feigelson was not the only one trying to improve his diamond making method. There were at least five labs spread around the old Soviet Union - from Moscow to Siberia. And even though their diamonds were yellow in color and far from flawless, they were enough to set the alarm bells ringing at De Beers. De Beers, in fact, has been concerned about the threat of synthetic diamonds for years. Part of its defense has involved developing its own methods for growing diamond crystals.

ROBBIE BURNS: We've been able to grow a phenomenal range of diamonds, some of them quite large in fact. In fact some of these over here were grown in a growth run which lasted something like six weeks and they are 25 carats in weight each, grown four at a time, so we're actually quite proud of this.

NARRATOR: De Beers has no intention of selling these diamonds for use in the jewelry market. They are used only as tools for distinguishing between man-made and natural stones. Grown in Johannesburg, the diamonds are sent to De Beers Gem Defense laboratory outside London. It is here where research scientists like Paul Spear look for ways to thwart the diamond makers. Over 100 people are employed to identify the tiniest difference between the new synthetics and natural diamonds. As their laboratory-grown diamonds have become ever more perfect, De Beers has had to invent new methods of detection.

PAUL SPEAR: De Beers' aim is to instill confidence in the diamond consumer that their diamond is a natural diamond, and not one made by man. There are very few synthetic diamonds available in the trade. But it's very important that, although there isn't a current threat from synthetics, that we need to look to the possibility in the future that there might be a threat, so we need to be well prepared.

NARRATOR: But the threat may be increasing as Russian labs find ways to rid their gems of the telltale signs of manufacture. The biggest problem is eliminating tiny pieces of metal trapped in the growing diamonds.

PAUL SPEAR: This diamond contains quite a number of inclusions. I'll zoom in on one of those. And you can see how this inclusion, a metallic inclusion, has actually grown roughly in the shape of the growing diamond, so it's partially faceted. And these come from the metallic solvent used to grow the diamond. Of course, this microscope has a limited power. But the point is, it's what the gemologist can see easily with his standard tools.

LECTURER: Metallic inclusions are solidified remnants of the flux metal from which the synthetic diamond is grown in the laboratory.

NARRATOR: It is a lesson that De Beers wants to teach gemologists around the world. In gem testing centers, classes are held in synthetic diamond detection using diamonds produced in De Beers' own laboratories. These gemologists learn how to pinpoint synthetic diamonds by zeroing in on their metal inclusions. To eliminate metal inclusions, the Russians had to control the atomic growth of their crystals in a far more exacting way. They had to prevent the metal, seen here in blue, from joining the carbon atoms as they formed the diamond. The metal was finding its way in because the carbon atoms were flowing unevenly. The key to keeping the flow constant - and the metal out - was controlling the temperature.

BORIS FEIGELSON [voice over translation]: It was clear to us that we had to refine the chemistry and stabilize the heating process as much as possible, and that would control the temperature.

NARRATOR: Through a process of trial and error, constantly adjusting the heat on each end of the growth cell, Feigelson learned how to control the temperature gradient. After hundreds of experiments, he found a setting that made the flow of carbon atoms more constant. These minute adjustments helped keep the metal from attaching itself to the growing diamond seed - but exactly how he did it is something he won't divulge.

BORIS FEIGELSON [voice over translation]: How we solved it is a top secret, but thankfully finally we managed to solve it.

NARRATOR: Feigelson finally achieved his aim: he was able to create a diamond that was metal-free. But the next problem he and all other diamond makers faced was that their diamonds were yellow. The color is caused by nitrogen from the atmosphere getting into the presses.

MARK NEWTON: Any synthetic diamond you grow will have a lot of nitrogen in the structure, and this nitrogen is incorporated as a single substitutional nitrogen atom, isolated nitrogen atoms dotted around the diamond lattice. The consequences of having nitrogen there is it gives the diamond color, the nitrogen impurities set up an absorption of light and it gives the diamond a not very attractive brown color.

NARRATOR: Natural diamonds also contain nitrogen, but over millions of years the pressures and temperatures in the earth's mantle concentrate the nitrogen atoms together into imperceptible clusters and reduce or eliminate the yellow color.

MARK NEWTON: The nitrogen atoms have hopped around and formed aggregates where more than one nitrogen atom is bonded together. There's two atoms bound together in what's called the A aggregate, four atoms in the B aggregate, and in this form the nitrogen doesn't give rise to any optical absorption in the visible, which means the diamond looks white. It's still got the impurity in there but it just, the light is now not absorbed in the visible wavelength.

NARRATOR: The problem of redistributing the nitrogen to reduce the yellow cast was one that the General Electric diamond makers had already grappled with.

HERBERT STRONG: You can take such a yellow diamond with nitrogen in it and heat it for a long time. Hours. And the yellow gradually disappear because the nitrogen atoms begin to combine with each other, but it's a very long, slow process and we never got one to go pure colorless, but we just did enough to show that that was the way natural diamonds come out colorless sometimes.

NARRATOR: Today, in Provo, Utah, others are busy perfecting the methods for creating colorless diamonds. In this factory, a 5,000 ton press can generate the kind of pressure needed to concentrate the nitrogen in diamonds. It is a process that is being developed by the sons of GE diamond pioneer, Tracy Hall.

H. TRACY HALL, JR.: So if you can heat the diamond hot enough that there is considerable diffusion, mobility of atoms, then you can allow the nitrogen atoms to find each other. The problem is you can't heat diamond hot enough at atmospheric pressure. It will turn to graphite. And so people who have a press can get the diamond much hotter than you could in an atmospheric furnace.

DAVID HALL: It's like putting the diamond back into the earth. Way down there, just like Mother Nature did.

NARRATOR: But no one has found a way to do more than concentrate some of the nitrogen - enough to turn a brown diamond yellow, but not enough to make it colorless. What the diamond makers needed was a way to prevent the nitrogen from getting into the diamond at all.

BORIS FEIGELSON [voice over translation]: To get colorless diamonds what we had to do was get rid of the nitrogen which gives them their yellow color.

NARRATOR: A clue for getting rid of the nitrogen came from General Electric's work 20 years before which suggested that the nitrogen atoms could be chemically attracted away from a growing diamond by using what was called a nitrogen "getter." The nitrogen getter Feigelson chose was aluminium. Feigelson found that by putting aluminium in the growth cell, it melted into the metal solvent and the nitrogen atoms were irresistibly drawn towards it, leaving the carbon atoms free to form as pure and colorless diamond.

BORIS FEIGELSON [voice over translation]: When we got our first good diamonds we were absolutely overwhelmed. They have the same characteristics as real diamonds, the same hardness, same conductivity, the same sparkle.

NARRATOR: Feigelson managed to remove the nitrogen and metal inclusions from some of his crystals, but he has not been able to make many. Despite this modest output, clear and colorless diamonds like these could still turn into a nightmare for De Beers.

PAUL SPEAR: Clearly with a near colorless diamond, if there are no clues such as the presence of inclusions, then a microscope is very little help to you.

NARRATOR: While Feigelson appears more interested in diamond science, a bigger threat to De Beers comes from a group of diamond makers in Siberia who want to mass produce gems. Scientists have been making diamonds at the Institute of Geology in Novosibirsk for more than 20 years, but with state funding drying up, money has run out. They too have had to look for new business opportunities. What they have to offer is experience in the science of making gem-quality diamonds. Desperate for money to keep the Institute running, they have been forced to look abroad for investment. In return for the Institute's know-how, an American company in Florida has invested millions of dollars in a joint research project to make synthetic diamonds a commercial reality. It is headed by retired Army general Carter Clarke.

CARTER CLARKE: Our two years of operation so far has been devoted to be able to insure ourselves that we can produce the same quality, the same size, the same consistency, the same color time after time. We have now accomplished that, so we're now ready to go into the commercial side of this business.

NARRATOR: The Russians are now packing up some of their presses to send to Clarke in America. If his new production line works, it will be the first time that synthetic gem diamonds, in a variety of sizes and colors, will be produced for the mass market.

CARTER CLARKE: We started off where ours were taking one carat diamond in about 72 hours. That roughly equates to about 1.8 milligrams per hour of growth. We now have that up to eight milligrams per hour of growth, which means we can produce a one carat diamond in roughly 24 hours. We expect to get that down even further, and so it's just a matter of how many machines you have.

NARRATOR: Like most diamond dealers, Carter Clarke will be selling his wares here, at the world's biggest gem fair - held every year in Las Vegas.

MARTIN RAPAPORT: A synthetic diamond by itself is no problem, as long as the industry maintains rules of detection and disclosure, that means scientifically, gemologically, the industry is able to detect that a certain type of diamond is a synthetic, is not a natural stone.

NARRATOR: But what if some diamonds makers refuse to play by the rules, gambling that they can pass their diamonds off as natural stones?

STEPHEN LUSSIER: A consumer in the old days easily could tell an imitation from the real thing. Now it's a bit more tricky. De Beers' role really is to make sure that we can always do it, and that we can always make that discrimination for the consumer.

NARRATOR: Faced with a potential crisis of confidence caused by the new synthetics that are undetectable under a microscope, De Beers has been forced to look at the atomic structure of natural and synthetic diamonds to find the tiniest difference. And that has required new and more sophisticated technology.

PAUL SPEAR: One of the properties of diamonds is that they, they emit light when it's sighted by laser light, or light of other wavelengths. Synthetic diamonds and natural diamonds, because the nature of the defects are different in both types of diamond, emit different types of light, different types of spectra because the defects are different. So we can actually distinguish spectra, and the defects would discriminate synthetic from natural diamond using this equipment.

NARRATOR: After hundreds of experiments, De Beers' scientists have identified what they believe is a unique difference in synthetic diamonds.

PAUL SPEAR: This is a very intense short-wave ultraviolet lamp, and what we see here on the left are four synthetic diamonds and on the right four natural diamonds, and we're looking at the luminescence which is given off by the diamond. And you can see that on the left the four synthetic diamonds are glowing very brightly under the action of this very hard ultraviolet light, but as the four natural diamonds are almost inert under the action of this ultraviolet light. And of course from synthetic diamonds you see phosphorescence when the lamp is turned off - the diamonds glow in the dark.

NARRATOR: This work has traced the cause of phosphorescence in manufactured diamonds to the way they grow. Natural diamonds have an octahedral structure. But synthetics, because they grow in an artificial environment, also form cube shaped sectors. It is this mix of cube and octahedral growth that causes man-made diamonds to absorb ultraviolet light differently.

PAUL SPEAR: If we look at the image here you can see here where the seed crystal was positioned for the synthetic diamond to grow from, and here are the octahedral growth sectors which are fluorescing. If you rotate the diamond round, you see these octahedral growths sectors have grown larger, and at the same time that initial small cubic sector has grown much larger as well, so this very simple growth sector structure is indicative of a near colorless synthetic diamond.

NARRATOR: Because of the way defects like nitrogen concentrate in the growth sectors of synthetic diamonds, light is held back and released slowly, causing this unique phosphorescence. The hardware De Beers developed to observe this phenomenon is called Diamond View.

PAUL SPEAR: What the camera has done, it's waited for the lamps to turn off, waited a short time and then looked to see whether there's any residual luminescence, termed phosphorescence, and indeed there's a very, very high level of phosphorescence on this diamond. Every diamond that we've looked at with these instruments, every synthetic diamond we have looked at, are always trapped by the Diamond View.

NARRATOR: The Diamond View machine is not available to the average dealer, but it does offer a way to pinpoint one key distinguishing feature of synthetic diamonds that suggests that diamond makers may never be able to replicate the passing of time in nature.

ROBBIE BURNS: This difference has given natural diamond properties and a structure which is very different to synthetic diamonds, and in the laboratory I can't see a simple way of being able to bridge that time difference.

NARRATOR: In what is becoming a scientific cat and mouse game, De Beers has defeated the diamond makers at an atomic level. But even this is being challenged.

CARTER CLARKE: When you send one of our diamonds to De Beers, right, the only way they can detect that this is not a natural diamond is really through phosphorescence. They take this, and they put in, they hit it with a UV light, and after the UV light goes off, this thing will phosphoresce for about three to five seconds. That is typical of a synthetic diamond versus a natural diamond. Something you would not do in a jewelry store, for an example. However, we have a way to overcome that.

NARRATOR: As yet, there is no evidence that any diamond makers have found a way to overcome the phosphorescence problem - but the game is likely to continue. One team of Russians is trying to grow diamonds in conditions closer to those in the earth's mantle. Much of this technology is secret, but because they are using a carbonate rather than a metal solvent and lower temperatures in their presses, their tiny diamonds have the pure octahedral form of natural diamonds.

YURI PAL'YANOV [voice over translation]: Today we can grow diamond crystals in conditions which are more like nature and that creates more natural looking diamonds, but as in nature, the speed of the process and the speed at which the diamonds grow is extremely slow.

NARRATOR: Tiny crystals like these represent the latest effort to make diamonds under conditions closer to nature. These scientists claim that eventually they will be able to grow these minute diamonds into gems, indistinguishable from a natural stone. But how realistic is this claim?

ROBERT HAZEN: We are entering an era of what I call atomic architecture. We seem to be able to build up structures atom by atom by atom in almost any conceivable way that we want. Is it possible for humans to synthesize diamonds that are absolutely indistinguishable from a natural stone? And I suppose the answer has to be yes. Will people try? I'm sure they will. Because of course if you can fool the gemologist into thinking you've got a big natural stone, you can make a lot more money.

NARRATOR: Faced with the future threat of synthetic diamonds being imperceptible to the trade, De Beers is already preparing its bottom line - one low-tech way to guarantee detection. They are putting minute logos on their diamonds.

STEPHEN LUSSIER: If we can give the consumer a little bit more help in telling him what's a good diamond, that regardless of what they know or what their jeweler knows, De Beers has told them that this diamond is natural from - as it came out of the ground, created by nature billions of years ago and not one that popped out of a machine last Wednesday in Kansas City.

NARRATOR: Some day the science of diamond making may become so ingenious that even experienced dealers won't be able to distinguish between man-made and natural diamonds. For the diamond makers, this means that the only real difference is in the mind.

HERBERT STRONG: I would have to conclude that if you have to have gems, you can make just as beautiful gems out of man-made as nature can.

NARRATOR: But what will it mean to the consumer?

STEPHEN LUSSIER: I always think it's a bit like a masterpiece from Picasso and a copy. In the end, one is worth $30 million and is a magnificent treasure of the world, and the other is a worthless copy. CARTER CLARKE: We have asked many women whether they would prefer a four carat synthetic diamond or a two carat natural diamond, if all else was equal: the characteristics, the features, the chemical composition, all those things were the same, which would they take? I've never had anyone say they wouldn't take the big one.

HERBERT STRONG: These man-made diamonds are also forever, just as forever as any natural diamond is, and maybe then some.

____: Diamonds exist not only on earth, but up in the heavens. On NOVA's Website find out about diamonds in meteorites, on other planets, even in the remnants of exploded stars.

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