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A Diamond
BBC Two, Thursday 4 March 2004, 9pm
Diamond Labs
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Diamond Labs - transcript

NARRATOR (NEIL PEARSON): Diamonds are the most prestigious of all gems, originally the domain of royalty diamonds bring glamour, sophistication and class. But diamonds are so rare in nature they don’t come cheap.

JEREMY NORRIS (David Morris International): This is the classic ten-carat emerald cut which I’m sure every woman would love to own and that’s around six hundred and fifty thousand dollars.

NARRATOR: But how would you feel if you could get your hands on top quality merchandise for a fraction of the price? We’re not talking about fakes, but diamonds grown in a lab.

Prof BOB HAZEN (Mineral Scientist, Carnegie Trust): Synthesising diamonds, they’ve been a holy grail. For physicists, for chemists, for two hundred years people had tried to make diamonds and they had failed.

NARRATOR: The possibility of being able to mass produce high quality diamonds has sent shock waves through the multi-billion dollar diamond industry.

MARTIN RAPAPORT (Publisher, Rapaport Diamond Report): What if there is a way to synthesise diamonds that are non-detectable from natural diamonds? What if technology uses the ability to make these synthetic diamond and no one knows it’s synthetic?

NARRATOR: This is the story of the diamond makers, and how one day these fabulous gemstones may become available to us all.

NARRATOR: On the outskirts of Boston, hidden away in a secret lab, a father and son team were hoping to become fabulously rich. They were trying to grow in their laboratory the most valuable gemstone known to man. No one knew if it would work.

Dr ROBERT LINARES (Apollo Diamond): Following growth you always put the diamond in to a, an acid bath, to clean off any graphite that’s on the surface. So we put this, these in, left it over the weekend.

NARRATOR: They had spent years refining their technique, but so far every attempt had failed. But checking in on that Monday morning Robert Linares noticed something very odd. At first it seemed that not only had the experiment failed but the diamond had disappeared completely.

Dr ROBERT LINARES: Came down on Monday and we didn’t see the diamond there. We saw nothing. And then we looked further and we noticed that the crystal was there. But it was perfectly transparent, it was perfectly colourless. It was like someone had pulled a hood off of our heads and we could see the truth. And at that moment we knew we had crossed a huge barrier and we could now make very perfect diamonds.

NARRATOR: Robert Linares had achieved something that had eluded science for centuries. He had made a gem quality diamond to rival the very best found in nature. A breakthrough so astonishing that it might revolutionise the multi-billion dollar diamond market. Diamonds are the ultimate statement of luxury, glittering and sexy they’ve never gone out of fashion. Even today there are plenty of women who believe diamonds are a girl’s best friend.

STEPHEN LUSSIER (De Beers): Our job as marketers is not to make women want diamonds I can tell you, they want them before we start, our job is just to help them to get them. I talk to enough women around the world about diamonds to know what it is that they, that they dream about. They dream about owning a piece of eternity.

NARRATOR: What makes diamonds so special is that they sparkle like no other gemstone.

MARTIN RAPAPORT: It has that unique combination of life and brilliance and class, it really makes you feel special when you're looking at it.

NARRATOR: Such is the allure of these rocks that people go to extraordinary lengths to get their hands on them.

NEWS READER: Good evening, five men who tried to pull off the biggest robbery in history were jailed today for a total of seventy four years, when they tried to steal two hundred million pounds worth of diamonds on display at the Millennium Dome. They got as far as smashing a supposedly bombproof display case, but the flying squad knew all about the plot and they were waiting in ambush. One said I was only twelve inches from payday, it would have been a blinding Christmas.

NARRATOR: Diamonds occur naturally in the ground, but digging them out is immensely difficult. With mines located in some of the world’s most inhospitable places, it’s a dangerous and very expensive business. You have to shift over two hundred tonnes of rock for every carat of diamond. But ironically diamonds, for all their fire and sparkle are actually just a very hard version of an extremely common element, diamond is nothing more than a lump of carbon. In nature pure carbon is more readily found in a different form as soft black graphite.

Prof BOB HAZEN (Mineral Scientist, Carnegie Institute): 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 coordinated to three other carbons, and that leads to very strong layers. But the bonding between the layers are exceptionally weak.

NARRATOR: But if that bonding is rearranged something remarkable occurs.

Prof BOB HAZEN: By contrast diamond is 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 neighbours. And if one is a complete three-dimensional structure, 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: The difference between the two forms of carbon is so subtle that scientists have searched for ways of transforming cheap graphite in to much more valuable diamond.

Prof BOB HAZEN: Synthesising diamonds had been a holy grail for physicists, for chemists, for two hundred years people had tried to make diamonds and they had failed.

NARRATOR: That two centuries long quest began with a worldwide hunt for clues. The very first came from the way diamonds were formed in nature. It’s believed that diamonds are created two hundred kilometres beneath the earth’s surface, and that they can take millions or even billions of years to form. It’s then during rare and exceptionally violent volcanic eruptions that diamonds are blasted to the surface within a rock called kimberlite.

Prof BOB HAZEN: Finding diamonds in kimberlite gave hints to how diamonds were formed. It told you you needed high temperature and high pressure because that’s where the kimberlites came from, this volcanic rock from deep in the earth.

NARRATOR: The task facing would be diamond makers was to mimic the vast pressures and savage temperatures found deep in the earth, and to do it, not over millions of years, but in days. No one got close until the 1950s, working in the greatest secrecy in the engineering company General Electric, a team of American scientists took up the challenge. They aimed to create diamond from graphite. GE spent millions of dollars developing a gigantic four hundred tonne diamond press. It produced pressures up to sixty thousand atmospheres and temperatures topping three thousand Celsius. But they were making little headway.

Dr HERBERT STRONG (Former GE scientist): Thoughts very much worked on, on, on trying to convert graphite, or carbon in to diamonds. Well, going straight from graphite to diamond didn’t, didn’t work.

NARRATOR: For four years all they got was broken presses. There was something missing in their chemistry so they looked for new clues. In a meteorite crater in Arizona diamonds had been discovered encased in a substance called troilte, or iron sulphite. These diamonds were formed by the high pressure and temperatures created during impact. The GE scientists believed that troyalite might be the missing ingredient needed to convert graphite in to diamond. So they had another go.

Dr TRACY HALL (Former GE scientist): It was a wintry day, it was cold but the sun was shining through the window. And I had put some troyalite in this graphite tube, I put it in my apparatus, I turned up my heating system and I put the pressure on.

FOOTAGE VOICE OVER: The force builds up and up and up, eventually reaching nearly five hundred tonne, almost one million pounds per square inch, the outer surfaces reached seven hundred and fifty degrees Fahrenheit. Inside two thousand six hundred degrees Fahrenheit.

NARRATOR: They could only risk running their machines for a few minutes, but they hoped it would be enough. Then just as they’d done dozens of times before they broke open the capsule.

Dr TRACY HALL: I got down to the point where I picked things apart and got to look at what’s there in the middle. And my eyes caught a gleam of the sun shining on these things. And I twiddled it around a little bit and saw the sparkles. My knees weakened, I had to sit down, I was overwhelmed. And at that instance I knew that man had finally turned graphite in to diamond.

Dr HERBERT STRONG: The headlines in all the newspapers around the world, it had G E making diamonds now. Wow 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.

NARRATOR: But for all this triumph GE’s diamonds were nowhere near good enough to adorn the neck of a movie star. Nevertheless their grit-sized grains didn’t go unnoticed in the boardroom of the most powerful diamond-producing cartel in the world. De Beers is the diamond industry, and it’s dominated the market for well over one hundred years.

STEPHEN LUSSIER: We’ll sell in the neighbourhood of five billion dollars worth of rough diamonds. I would have thought a figure north of a hundred million carats a year total rough production. Somewhere between fifty and sixty percent of the world’s supply.

NARRATOR: From their headquarters in central London De Beers’ rough diamonds are sorted and distributed around the world. Sold to select dealers for cutting and polishing. For years De Beers have maintained extraordinary levels of control on the sixty billion dollar global diamond market. Initially they didn’t see the arrival of manmade diamonds as a threat, they were just too low quality, fit for only making industrial cutting tools. However De Beers did see potential danger in the future if diamond-making technology improved. So at a discreet facility on the outskirts of London, De Beers created the Gem Defensive program. At vast cost the new scientific division was set up to develop techniques to distinguish between natural and synthetic diamonds.

STEPHEN LUSSIER: Clearly we knew that some day synthetic gems would be made available in the consumer market. The crucial thing for us was to make sure that first the industry but more importantly in the end consumer had every means possible to ensure we could detect the simulant from the genuine article.

NARRATOR: With their scientists busy working away De Beers were confident they had time in hand to prepare for any future threats. But unknown to De Beers a challenge already existed hidden away behind the iron curtain. With the break up of the Soviet Union Russian scientists were keen to explore the new ideals of capitalism. In the early 90s on the outskirts of Moscow diamond scientists Dr Boris Feigelson set up a lab in rooms rented from the Institute of the Blind.

Dr BORIS FEIGELSON - TRANSLATION (Diamond scientist): I had hopes, I even had dreams about it. That was at the time when things started to happen.

NARRATOR: His original idea was to copy General Electric’s theory of high pressure and high temperature. But instead of tiny grains he planned to grow gem size diamonds. But he just didn’t have the right gear. With little money he had to use whatever equipment came to hand. His first attempts were wrought with danger.

Dr BORIS FEIGELSON - TRANSLATION: We had to select the right material 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, every thing would come flying out at high pressure.

NARRATOR: In the end in contrast to the giant machines used by General Electric, Feigelson cobbled together a diamond press not much bigger than a washing machine. At its heart was a small spherical growth chamber which used a unique method to create the required high pressure. Pumping oil around the sphere created a moderate hydraulic pressure. This was then amplified through specially shaped steel anvils to create a massive fifty eight thousand atmospheres down at the central core. But at first he still wasn’t getting the goods.

Dr BORIS FEIGELSON - TRANSLATION: When we thought we understood everything, everything was clear. Then something emerged, something no one predicted, and everything fell through.

NARRATOR: Feigelson decided to try an old crystal-growing trick and give his diamond a head start. Within the growth core he added a tiny piece of low quality grit diamond. He hoped this would act as a seed on which the growing diamond could form, above it was a metal solvent and a layer of graphite. He then applied an electric current to heat the top of the chamber. This dissolved the graphite in to the metal solvent releasing the carbon atoms, the carbon atoms migrated through the molten solvent to the cooler end of the capsule, where they crystallised on to the diamond seed making it grow.

Dr BORIS FEIGELSON - TRANSLATION: We managed to get sometimes quite good crystals, but more often the results were not good.

NARRATOR: Feigelson’s diamonds had telltale signs which would betray their manmade origins. They often contained small fragments of metal.

Dr BORIS FEIGELSON - TRANSLATION: It was clear to us that we had to refine the chemistry and stabilise the heating process as much as possible.

NARRATOR: Feigelson eventually discovered that by controlling the critical temperatures within the growth core in a very precise manner he could dramatically improve the quality of his diamonds. His diamond growing technique was still not consistent but Feigelson had realised his dream. But there was something else about his diamonds, something that made them potentially of extraordinary value. His diamonds weren’t crystal clear, they were coloured.

Dr BORIS FEIGELSON - TRANSLATION: When we got our first good crystal we were naturally absolutely overwhelmed.

NARRATOR: Coloured diamonds are found in nature but they’re extremely rare, among their number are the great legends of the diamond world, like the Hope diamond, the Dresden Green, the Tiffany Yellow, and the recently unveiled Blue Empress. Fancy coloured diamonds are highly prized and they’re hideously expensive. Only the finest jewellers stock natural coloured diamonds. Jeremy Morris has been in the family business for twenty years.

JEREMY MORRIS: Wealthy people have the market for vivid and fancy intense colour diamonds, it’s not for the average person, the price is prohibitive, unfortunately. This stone here is, it’s a little freak of nature, it’s six carat, deep brownish, orangey yellow, but that would be around three hundred thousand dollars. One-carat twenty-five, vivid orangey yellow, dazzlingly beautiful, thirty eight thousand pounds. We have here a twenty-five carat light pink one and a half million dollars, or nearest offer.

NARRATOR: The lucrative trade in fancy coloured diamonds was a market the Russian diamond makers were keen to exploit.

Prof BOB HAZEN: It’s possible to make duplicate Hope diamonds or red diamonds or yellow diamonds or green diamonds, all different sorts of colours of diamonds just by controlling the right impurity, a slight change in the chemical mix that goes in to making these diamonds.

NARRATOR: But if the diamond makers were going to stand any chance of selling their rocks first they had to convince the diamond dealers of the West. Every year Las Vegas hosts one of the world’s largest gem fairs, where thousands of dealers sell their wares to jewellers from around the world. In 1999 coloured synthetic diamonds coming out of Russia were show cased here for the first time.

MARTIN RAPAPORT: Just today we had here at the show a large selection of synthetic diamonds presented and shown to us in a riot of fancy colours, you're talking about blue stones that look like one hundred thousand dollar per carat stones, very nice stones.

NARRATOR: Lured by the dream of fabulous wealth diamond labs had sprung up all over Russia. As a middleman for synthetic diamonds Alex Grizenko had been drawn to Vegas.

ALEX GRIZENKO: Through the last several years we have been looking at what the potential market could actually be. Today the market is truly in its infant, infant stage. And as demand grows, and demand has to grow, this market has to be created, and as demand grows so will supply, inevitably, it will be a big market.

NARRATOR: But back in 1999 the prospect of a world flooded by synthetic Russian diamonds actually seemed remote. Their labs lacked the funds and the necessary production skills.

ALEX GRIZENKO (Synthetic diamond dealer): The Russians certainly have problems today, we all understand that. Capital is scarce, infrastructure is in some places complicated, capital investments in to Russia today are difficult.

NARRATOR: But a chance meeting was about to change all that. Like something out of a James Bond movie a Russian scientist made a cautious approach to a former US army general. It was to be a fateful encounter.

General CARTER CLARKE (The Gemesis Corporation): I was in Moscow on another project, developing an electronic security device, and one of the scientists on the project asked me whether or not I was interested in diamond. And I said well I’m an entrepreneur, I’m interested in most anything. Frankly I thought he was going to ask me to invest in some diamond-mining project. But instead he took me to a facility outside of Moscow and they, they showed me a machine that they claimed would make diamonds.

NARRATOR: General Carter Clarke was intrigued. But even though he decided to fork out one hundred and seventy thousand dollars for three units, he was quite sceptical that the Russian machines could make anything at all.

General CARTER CLARKE: The machines they had in Russia were doing experimental work, and there’s a big gap between a laboratory type of operations and a commercial production. We really had to bring good old Yankee ingenuity in to being in order to make this a viable business.

NARRATOR: So he brought the whole operation back to his native Florida, there he set up shop as the Gemesis Corporation, his ultimate plan to mass produce synthetic diamonds. But straight away it was clear the Russian machines just weren’t doing the business.

General CARTER CLARKE: They were able to get a crystal once in a while but not all the time, they couldn’t get the size we wanted, they couldn’t get the colour we wanted, couldn’t get the consistency we wanted, couldn’t get the yield we wanted. The whole idea of the growth process had to be rethought.

NARRATOR: So General Clarke enlisted the help of scientist from the University of Florida, Dr Rob Chodelka identified the problem, too much human intervention.

Dr ROB CHODELKA (The Gemesis Corporation): When the machines initially came over, one of the large problems were they were manually operated. There was a person sitting in front of that machine twenty-four hours a day, seven days a week, while that machine was running, controlling the principle properties for that machine to operate, the pressure and the temperature. We wanted to remove the human error associated with running and operating this machine, so we could produce a product on a consistent basis. That was we had to computer control it.

NARRATOR: The University scientists attempted to automate the growth process entirely, no one had tried this before, but eventually they managed to convert the machines. Using their updated design Clarke’s technicians started building their own presses, ultimately creating the world’s first gem diamond production line. Each of his twenty-three machines could then be prepared and loaded in minutes, now it was simple case of pressing start and waiting for the machine to do in four days what nature does in four million years.

Dr ROB CHODELKA: It’s a short period of time, about eighty-two hours, is our heat compressured cycle, and in that time we use about fourteen hundred watts of power, equivalent to a hairdryer running at the same time.

NARRATOR: After each machine finished its run the growth cores were extracted. They were then cracked open to reveal a small lump of metal which contained the diamond. These were then each washed in acid baths to dissolve away the metal, revealing the newly formed rough diamond. Clarke was finally on his way to achieving his goal, he was now producing fancy yellow diamonds, far superior in size and quality to anything ever created in the Russian labs.

General CARTER CLARKE: Initially we were growing stones that were less than two carats, roughly about one point five, one point six and one point seven carats. Now we’re growing three to three and a half carats, and that will cut and polish to a stones that’s almost two carats, but depending on the cut that you want. We’re also getting a better colour, before we used to get a washed out yellow, now we get a nice vivid or intense yellow.

NARRATOR: Until now it had only been the ‘über rich’ who could afford natural coloured diamonds. Clarke dreamt of taking his coloured diamonds out on to the high street.

General CARTER CLARKE: These diamonds from nature are very expensive, a one carat, vivid yellow diamond would go somewhere between fifteen and twenty thousand dollars. Our comparable stone would go somewhere around four thousand dollars.

NARRATOR: Admittedly not for everyone’s pocket, but high quality synthetic stones selling for a quarter of the price of naturals sent ripples across the diamond pond. For the first time there was a real threat of synthetic gem quality diamonds flooding the market, and undermining the traditional diamond trade.

MARTIN RAPAPORT: The concern in the industry today is what if, just what if there is a way to synthesise diamonds that are non-detectable from natural diamonds? What if technology uses the ability to make this synthetic diamond and no one knows this is synthetic?

NARRATOR: This possibility was not lost on the world’s largest diamond trading company, De Beers. Unless they could respond decisively they might lose their dominance of the market. Their first tactic, simply dismiss the competition, unless it came out of the ground it just wasn't the real thing.

STEPHEN LUSSIER: Diamonds are just so much more than just crystallised carbon, diamonds are something from our, from our deep, deep past, billions of years old, a miracle of nature, you can't replicate that in a laboratory yesterday in, in Florida, it’s not possible.

NARRATOR: De Beers gem defence program then sprang in to action. Millions of dollars had been spent developing various machines to tell synthetics from the natural stones. The problem they faced was that synthetics were now very high quality, it forced them to study down to the diamond’s atomic structure, to detect even the tiniest differences.

Dr SIMON LAWSON (Gem Defensive Projects, De Beers): This instrument is Diamond Sure, it’s our rapid screening instrument that’s been designed to pass natural diamonds, whilst at the same time referring all synthetic diamonds.

NARRATOR: Diamond Sure works by analysing the way light is absorbed by a diamond. It’s down to how nitrogen impurities form within the crystal. Nitrogen atoms occur in clumps in ninety eight percent of all natural diamonds. This causes light to be absorbed in a specific way, and provides the key to their detection.

Dr SIMON LAWSON: This has got a pass result, the user can be confident that this is a natural diamond, and requires no further testing. I’m now going to place a yellow diamond on to the probe, press the test key, and this time within a few seconds it’s come up with a different result, it said refer for further tests.

NARRATOR: In yellow synthetic diamonds nitrogen doesn’t exist in clumps, but instead as single atoms, dispersed throughout the crystal, this causes light to be absorbed differently, which is picked up by the machine. Any questionable stones then get transferred to De Beers’ next line of defence, the Diamond View machine.

Dr SIMON LAWSON: Diamond View shines ultraviolet light on to the diamond and generates a surface florescence image from which synthetics may be unambiguously identified.

NARRATOR: Under ultraviolet light both natural and synthetic diamonds will glow to some degree, this is called fluorescence. But it’s the patterns that are revealed by this glowing fluorescence that can tell the two apart.

Dr SIMON LAWSON: It’s immediately obvious from the strong blocky blue fluorescence patterns that this is a synthetic. You wouldn’t get these strong shapes of blue florescence from a natural.

NARRATOR: Under the UV light natural yellow diamonds look very different, producing a consistent yet very faint blue glow. With technology like this De Beers feels it can out rightly dismiss the threat of synthetics.

STEPHEN LUSSIER: Today we can, you know, easily detect each and every synthetic stones that’s made. That’s really important to maintain industry confidence.

NARRATOR: De Beers were able to prevent any lab grown coloured gems from being passed off as natural diamonds. No synthetics could trick their way in to De Beers multi-billion dollar industry. But none of this phases General Clarke, he’s starting to make serious headway in to creating his own industry for synthetic diamonds. The key to Clarke’s business plan is that he doesn’t intend to compete against De Beers.

GENERAL CARTER CLARKE: We do not want our diamonds to be passed off as natural diamonds. That wouldn’t do us any good, would not do the industry any good, and certainly would not do the consumer any good. So we’re very strong in our concern about that, and we’re taking every measure that we can to prevent that.

NARRATOR: All his diamonds are sent to the heart of the diamond district in New York City, to the International Gemological Institute. Here they are officially certified as being manmade. They are also subjected to a more invasive level of disclosure, and have their origin tattooed on them by laser. General Clarke’s aim is to establish an entirely new market of affordable coloured synthetic gems. Currently producing two hundred diamonds a month Clarke has grand plans for massive expansion.

GENERAL CARTER CLARKE: We have twenty-three machines in this facility right now, are growing diamonds twenty-four hours a day, seven days a week. And what our ambition is, is to fill this whole environment here with about two hundred and fifty machines in the not too distant future.

NARRATOR: Clarke’s plan would create an annual production of twenty five thousand high quality synthetic yellow diamonds. In the nearby town of Sarasota on the west coast of Florida his diamonds are already on sale.

KARL SHRODE (Jeweller): They’re absolutely beautiful, you couldn’t ask for more beautiful stones. It makes it for more everyday people to be able to afford beautiful fancy coloured diamonds.

NARRATOR: It’s too early to say if Clarke’s new market of coloured synthetic diamonds will ever pose a serious financial threat to De Beers. His output at the moment is just too small. And anyway for De Beers it’s the clear colourless diamonds that are the main thrust of their global empire, and that market was completely unthreatened, or so they thought. Shrouded in utmost secrecy a company called Apollo Diamond has been operating somewhere outside Boston, Massachusetts for the last two years. Highly protective of their technology they have rarely granted access to their laboratory. Horizon was never given the address, just taken to their production facility. The company’s founder, Dr Robert Linares, had never intended to get in to the diamond business. His interest had always been in semi-conductors.

Dr ROBERT LINARES: Previous company was manufacturing gallium arsenate wafers for very high frequency devices such as cell phones and radars, and at the time that was the ultimate semi-conductor. And after I left that company, I sold it, I want to go to the next highest performance semi-conductor and that was going to be diamond.

NARRATOR: Diamond has some unique properties that make it a material with all sorts of possibilities for the high tech industries.

Dr ROBERT LINARES: It’s the hardest material known to man. It has a highest velocity of sound, it has a highest thermal conductivity, and it has semi-conductor properties which exceed that of silicone and other materials.

BRYANT LINARES (Apollo Diamond): The real thrust is to develop new single crystal diamond technology and to create the ability to grow large diamonds for a semi-conductor and optical application.

NARRATOR: But it was while striving to meet these goals that they stumbled upon something utterly unforeseen and ultimately much more glamorous.

BRYANT LINARES: We’re actually seeing diamonds now that really have the ability to become diamond gem cells.

NARRATOR: In their mission to make semi-conductors they had discovered how to make clear colourless diamond.

BRYANT LINARES: It was a Eureka moment for this company, where we recognised that we could really do something tremendous in this sixty billion dollar market place.

NARRATOR: The Linares adopted a completely different approach to other gem diamond makers. A technique called chemical vapour deposition, or CVD. Unlike previous methods of growing diamonds it didn’t need high pressure or graphite, and was based on using two very common gasses.

Dr ROBERT LINARES: CVD diamond is done at very low pressures, less than one atmosphere. And you introduce two gasses, you introduce hydrogen and methane.

NARRATOR: But before the process could begin what they needed was a seed for each new diamond to grow on. These seeds were made of thin slivers of low-grade diamond. In preparation for growth they were sliced and shaped using a high power laser.

PATRICK DOERING (Apollo Diamond): When we have the prepared seeds we then load them in to the machine and what our process can do, is capable of doing is growing on multiple seeds at a time. We can load twenty-five, fifty seeds at a time, and really how many seeds we put in depends on the size of the individual seeds.

NARRATOR: When the growth chamber was closed the pressure was lowered and the seeds heated to around eight hundred Celsius. Hydrogen and methane were pumped in to the chamber, then using high power microwaves the mixture was ignited forming a gas plasma. Within this chemical soup highly reactive hydrogen atoms collided with the methane molecules releasing carbon atoms. These atoms were then attracted down to bond with the carbon atoms of the diamond seeds, and so the new diamonds grew, atom by atom. But initially there was a hitch, others had tried CVD but could only produce thin wafers of diamond, nothing like the thickness needed to create a gemstone.

Dr ROBERT LINARES: It was commonly thought by scientists around the world that you could never make diamond by the CVD process that was greater than fifteen microns thick, that’s far less than the thickness of a hair. We discovered how to cross that barrier, we discovered it for a couple of reasons, one of which was we had to because we were basing our future business on making single crystal that was thick. And once we figured out how to do it we very quickly went to a half a millimetre thick, one millimetre thick, three millimetres thick, five millimetres thick.

NARRATOR: To this day Robert Linares has not revealed the secrets of his technique, but within his machine he could now effectively watch three million years of diamond growth happening before his eyes. But there was something else, his diamonds had a clarity and structure unrivalled by any other synthetic process.

BRYANT LINARES: The gem diamonds that we make here at Apollo are very perfect. And they have the capability of being the most perfect diamonds that we have seen on the planet. The Naval research department here in the United States has called them the most perfect diamonds that they’ve ever seen, both manmade or natural.

NARRATOR: Finally scientists were not just able to match nature but make something even more perfect, and available at a fraction of the cost. It was the first serious threat to the traditional market in clear diamonds. De Beers’ scientists were now facing their ultimate test. Never before had they come against a cheap synthetic diamond that might be more brilliant than a natural one. If they couldn’t detect these new colourless stones then consumer confidence in their natural diamonds could take a hammering. Using their Diamond Sure device the clear CVD diamond was recognised as an unusual stone, but it still required further tests.

Dr SIMON LAWSON: Ok this is a colourless stones that has been referred by the Diamond Sure instrument, at this stage we don’t know whether it’s synthetic or one of the rare types of natural diamond, so I’m going to place it in to the stone holder and slide it in to the sample chamber of Diamond View. Focus the visible image on to the table of the stone. And now I’m going to shine the ultraviolet light on to the stone. This stone exhibits extremely intense orange florescence, which is a characteristic of CVD diamond. Natural diamonds would typically show a blue florescence.

NARRATOR: De Beers are confident in the ability of their equipment to detect these new colourless diamonds, they’ve sent their detection kit to gem labs around the world. But the question is will that be enough to protect them in the long run? Typically only diamonds above a certain size and quality are actually sent to labs for testing. The majority of us by tiny diamonds from high street jewellers, and while they may be precious to us diamonds so small are rarely sent to labs. The cost of testing them can be greater than their actual market value. As a result the authenticity of small stones, once in the market place, may never be questioned. This is an entirely new challenge to De Beers, but they are adamant they will do anything to keep their market safe.

STEPHEN LUSSIER: Maintaining consumer confidence in diamonds is worth any price that the De Beers group needs to spend to ensure it is there. You know the diamond to a consumer is a precious thing. They want to buy it with confidence, they want to know what it is, and anything we can do to help that we will do.

NARRATOR: But the fact is high quality synthetic diamonds now exist, and have the same fire and brilliance as naturals. Driven by the likes of Gemesis and Apollo Diamond creating brand new markets we now have the opportunity to buy synthetic diamonds. The only issue is whether you’d want to. Or do you think a diamond is worth more if it comes out of the ground?

MARTIN RAPAPORT: The only problem you’d have with synthetic diamonds is they’re not going to be as rare and they’re not going to be as special. I mean I could give you a Mona Lisa, it would be an exact copy of one, it would be fantastic, but the real thing is the real thing, and that brings out a very special feeling.

GENERAL CARTER CLARKE: You know if an orchid is grown in a hot steamy jungle in Central America or it’s grown in a hot house in California it’s still an orchid, it’s still very beautiful, women will love to have it and they don’t really care where it comes from.

JEREMY NORRIS: Where’s the romance when you, when you have a yellow diamond and you give it to your loved one you go, she’ll go wow that’s amazing, and you go yeah you know this is, this is a man grown diamond, and it’s like why didn’t you buy me a real one?

NARRATOR: It’s too soon to say if synthetic diamonds will catch on or if they’ll undermine the trade in natural diamonds. But there’s now a genuine chance that one day it could happen.

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