I just want to keep this interesting article as my personal archives on this blog, about the diamond makers from around the world, as a relax reading for you all and me, I found this article on the BBC website.
Well, let's make a cup of cappuccino coffee and enjoy your reading with this diamond jewelry article
TRACY HALL (General Electric, retired): 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 carbonised, it will turn to a graphitic-like material. So peanut butter to diamond.
DR ROBERT HAZEN (Carnegie Institute): I guess the question you've got to ask yourself is: is it possible for humans to synthesise diamonds till they're absolutely indistinguishable from a natural stone and I suppose the answer has to be yes.
NARRATOR (LINDSAY DUNCAN): There is something so special about diamonds and they are so valuable that people have always been prepared to go to the most extraordinary lengths to find them.
STEPHEN LUSSIER (Marketing Director, De Beers): 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 3 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: For hundreds of years people have bought into the mystique of diamonds and have been seduced by the hardness and brilliance that makes them so glamorous.
STEPHEN LUSSIER: The consumer actually wants a piece of forever. That's what a diamond is. It's a promise of forever.
NARRATOR: But how would we feel about the uniqueness of diamonds if it was possible to make one in a laboratory, just like the real thing, down to the nearest atom? In the last few years there has been a scientific race to do exactly this, to manufacture the perfect gem diamond.
DR BORIS FEIGELSON (RUSSIAN WITH ENGLISH TRANSLATION) (Diamond Scientist): Today the diamonds we produce are gem quality. They possess the same properties as natural real diamonds. They are exactly the same.
GENERAL CARTER CLARKE (Gemesis Corporation): Our diamond is so much cheaper to produce. It's more rare right now because we're not producing very many, but I don't think you could ever dig a natural diamond out of the ground, go through all the processes they have to have, for anywhere close to what we can make them for.
INTERVIEWER: How much can you make them for?
CARTER CLARKE: Less than $100.
NARRATOR: For hundreds of years people have tried to cash in by copying diamonds out of glass, paste and modern simulants like cubic zirconia, but these have none of the qualities of diamond because they are not made of the real thing. Fake diamonds can never equal nature because they are not made of the same unique material. In fact for centuries no-one knew what diamonds were made of. The only way to find out is to destroy one. In this lab a real diamond is being heated to over 1500 degrees Centigrade, then put immediately into liquid oxygen. The diamond burns away completely to leave: only carbon dioxide gas. There is just one material that reacts this way: pure carbon. Diamond is made out of pure carbon, but then so is graphite, the material we make pencils from. It's hard to imagine that this soft, dark substance is made out of the same thing as diamond.
DR 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 3 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 4 neighbours 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: The challenge for the diamond makers was to change the atomic structure of graphite, a soft and slippery substance, to diamond, the hardest, with a structure that refracts light in the most extraordinary way. No-one had got close until the 1950s. Nature's monopoly of the diamonds was challenged by the American engineering company General Electric. It was the beginning of the race to make diamonds. In the greatest secrecy, in Schenectady, New York GE started Project Super-pressure. Its aim was to make the world's first industrial diamonds with the same properties as natural diamonds. A young chemist called Tracy Hall was invited to join the team.
DR TRACY HALL (General Electric, retired): 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 and there's only one man we want, so I was the only one that held up my hand so I got the job.
NARRATOR: Then Hall was joined by a physicist, Herbert Strong.
DR HERBERT STRONG (General Electric, retired): And he said how would you fellows like to try to make diamonds. Huh, yeah, sure. I was enthusiastic about it, no thought of failure at all. No of course not.
NARRATOR: The diamond makers' first challenge was to break down the carbon atoms in graphite. Their problem was that graphite 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 'cos each carbon atom has 4 electrons that it wants to share with its adjacent atoms in covalent bonding so in graphite there are 3 adjacent carbons to every individual carbon sharing 3 electrons and then the fourth electron resonates within these ring-like structures adding additional strength to the graphite layer.
NARRATOR: The only clue the GE team had to turn graphite into diamond came from nature. Geologists knew that hypersonic explosions had brought diamonds to the surface as passengers in molten rock, that somehow 200 miles under the earth nature had turned graphite into diamond, that diamonds are found in the necks of extinct volcanoes.
ROBERT HAZEN: As a result, geologists found out that diamonds had to be high pressure materials, they were high pressure minerals and that was the key to diamond synthesis.
NARRATOR: The GE team had to find a way to replicate in minutes millions of years of pressure from a rock column 200 miles deep and the vast temperatures of the Earth's mantle. Only then might they be able to break down the atoms of graphite and reform them into diamond. But they had little idea what the right combination of temperature and pressure should be.
HERBERT STRONG: Just having a sense of how nature works you realise it was going to have to be way up here at very high temperature to get the atoms loose from graphite so they could go to diamond. It would have to be over 1,000 degrees Centigrade, probably higher than that. That was a guess and the pressure then would have to be up or diamond would be stable at that high temperature, it wouldn't go back to graphite.
NARRATOR: GE spent millions on diamond presses capable of focusing huge pressures and temperatures on the graphite capsule, 60,000 atmospheres and 3,000 degrees Centigrade, but still the graphite wouldn't turn to diamond. They had learned a crucial lesson.
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 4 years of broken presses Project Super-pressure was in trouble. The team knew that they had to find a way of making diamonds at lower temperatures and pressures or the project would be cancelled, but before they could make diamonds they had to find a way to break down the atomic structure of graphite. They had one more clue. Diamond may need high temperatures and pressures to form, but in one way it is no different from any other crystal, like ice. The individual atoms form together out of liquid solution.
HERBERT STRONG: What seemed logical to me was to dissolve the, the graphite into a solvent so as to get the carbon atoms loose and make 'em available for forming diamond. Well what is the solvent for carbon?
TRACY HALL: Well I had read that some tiny diamonds had been found in the meteorite crater that was in Arizona.
NARRATOR: In the 1950s it was discovered that this crater was made by a meteorite. When geologists looked at the meteorite diamonds they realised that they had been formed on impact.
DR SARAH RUSSELL (Natural History Museum): When the asteroid hit the Earth there 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: The GE team found another clue in that meteorite, something they thought must have helped form the diamonds. The diamonds were surrounded by metal.
SARAH RUSSELL: I've got a piece of the meteorite here and you can see this dark coloured 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 team were looking for. They hoped that this particular metal, called troilite when heated into a liquid state would act as a solvent to break down the carbon atoms in graphite. They tried adding some troilite in their growth capsule.
TRACY HALL: It was a wintery 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 2,600 degrees Fahrenheit.
NARRATOR: They hoped in this experiment that the carbon atoms in the graphite would dissolve into the molten troilite and then, when they had reached a high enough pressure and temperature, would crystallise as diamond.
HERBERT STRONG: We were in the hunch stage and my hunch was that when you're in the diamonds pressure region and you'd 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, 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 hoped that this would be enough for diamonds to form. Just as they had dozens of times in the past 5 years they broke open the capsule.
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 the gleam of the sun shining on these things and I, I, you know, twiddled 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, 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.
TRACY HALL: It was front page news in almost every newspaper in the United States overseas too, also and the people in the diamond people in, where would they have been, Antwerp, they were scared stiff.
NARRATOR: The diamond market had no reason to panic. Although the diamonds General Electric made had the same atomic structure as natural diamonds they were like grains of sand, but they revolutionised industry because just like natural diamonds, they were the hardest material in the world and they could cut through anything. But these tiny pieces of grit could never set a girl's heart racing. The science just wasn't there to make them sparkle. But for years no-one knew how to turn industrial diamonds into these. It takes millions of years for nature to grow gem diamonds and that is what makes them special.
STEPHEN LUSSIER: Women truly desire diamonds. It helps them sparkle brilliantly when, when they're wearing it. They like that feeling of wearing diamonds. The task of marketing really is only to help them achieve their desire of getting one.
NARRATOR: De Beers is the diamond business and this building is where they control the world diamond trade. By buying up most of the world's uncut diamonds the company can regulate supply to select dealers, increasing it in good years and reducing it in bad to keep prices high. Every year from this building £3 billion's worth of rough diamonds are distributed around the world for cutting and polishing. It is a cartel that has been built on the claim that diamonds have a unique appeal to women.
STEPHEN LUSSIER: The consumer actually wants a symbolic product and I think if the product is it forever there's no 3 billion years old. If it did just come out of a, you know, popped out of a machine 3 days ago it can't possibly have that symbolism.
NARRATOR: The beauty, glamour and cost of diamonds presented a new challenge for the diamond makers, to synthesise a gem quality diamond just like nature but in a fraction of the time. Now there are places in the world where nature's monopoly on gem diamonds is being challenged. Hidden behind the Iron Curtain industrial diamonds have been produced for years, but in a new Russia, scientists are becoming more ambitious.
In July 1993 Boris Feigelson set up his own lab in rooms rented from the Institute of the Blind. His plan was to grow industrial diamonds so they became as big as gems, but this required expensive high pressure equipment and with little money everything he did had to be built from scratch. To make large gem quality diamonds Feigelson had to find a way to make the diamond grit grow, but this meant running his presses at high temperatures and pressures for days. At the beginning this was impossible.
BORIS FEIGELSON (WITH ENGLISH 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 down from the metal solvent to the cooler temperatures at the bottom where they latch on to the seed. If the process is regulated carefully the seed grows. After 2 days of high temperature and pressure, these machines can each produce a one carat diamond, large, but flawed, with tell-tale signs of manufacture.
Boris Feigelson was not the only one trying to make gem diamonds. There are at least 5 labs spread around the old Soviet Union, from Moscow to Siberia, and they have all learnt the same basic skills of diamond synthesis. Even the earliest flawed diamonds the Russians made were enough to set the alarm bells ringing at De Beers. In fact De Beers had been taking this threat seriously for years. They have been growing diamonds in this laboratory to see if their own scientists can distinguish between synthetic and natural diamonds.
DR ROBBIE BURNS (De Beers): 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 6 weeks and they are 25 carats in weight each grown 4 at a time, so we're actually quite proud of this.
NARRATOR: The diamonds grown in Johannesburg come here to a research laboratory outside London. This building is the centre of the gem defence programme where they spend £3 million a year in a race with the diamond makers to maintain the confidence of their customers. 100 staff are employed to identify the tiniest difference between the new synthetics and natural diamonds. As the synthetics have become ever more perfect, De Beers have had to invent new methods of detection.
DR PAUL SPEAR (De Beers): De Beers's aim is to instil 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, in the trade and the vast majority of those, of course, are the yellow brown material. There are very few near colour stones, 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: While De Beers deny the diamond makers are a serious threat the trade is already feeling the heat. This is the world's largest gem fair. Thousands of diamond dealers selling their wares to jewellers' shops around the world, a £30 billion a year industry. It is a business that the diamond makers want a part of. Alex Grizenko is a middle man for other Russian diamond makers. He is here to sell the idea that man-made diamonds are intrinsically the same as the real thing.
ALEX GRIZENKO (Diamond Trader): You think on a philosophical level 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. Now as we know there are many simulants on the market. They're cubic zirconi has been around for many years. A new simulant called moissonite has entered the marketplace, but these are all pretending to be carbon. They're not carbon, and here the diamonds.
NARRATOR: The potential payout of synthetic diamonds entering the market place for the first time has already got the trade worrying about a doomsday scenario, the worst imaginable threat to the natural diamond business.
VOICE: You've hit the jackpot!
MARTIN RAPAPORT (Diamond Trader): 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 gives us the ability to make a synthetic diamond that no-one knows is synthetic.
NARRATOR: The trade may believe that diamond makers are far from producing undetectable synthetics, but behind the scenes the scientists have been working hard to rid their gems of the telltale signs of manufacture. The biggest problems were bits of metal that got trapped in the growing diamonds. They came from the metal solvent used to dissolve the graphite.
PAUL SPEAR: This diamond contains quite a number of inclusions. I'll zoom in on one of those and you can see how this, 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 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 are keen to spread to gemologists around the world. In gem testing centres classes are taught in synthetic diamond detection using similar diamonds supplied by De Beers.
LECTURER: In some cases synthetic diamonds can be attracted to a magnet as a result of the presence of these metallic inclusions…
NARRATOR: For these gemologists identifying synthetic diamonds with metal inclusions is as simple as putting them under a microscope.
LECTURER: The next slide please.
NARRATOR: To stop metal from ruining their diamonds the Russians had to control the atomic growth of the crystals in a far more exacting way. They had to prevent the metal from joining an interrupted flow of carbon atoms as they formed the diamond. They had to keep the flow of carbon so perfectly constant that the metal couldn't get near the growing diamond and the way to do this was to control the temperature within the growth cell in the most minute way.
BORIS FEIGELSON (WITH ENGLISH TRANSLATION): It was clear to us that we had to refine the chemistry and stabilise the heating process as much as possible and that would control the temperature.
NARRATOR: Feigelson adapted and refined an old idea. By minutely controlling the temperature gradient, hotter at the top to dissolve the carbon atoms into the metal solution and cooler around the diamond seed, Feigelson could ensure the carbon came out of the solution in a constant flow preventing the metal from reaching the diamond seed. After hundreds of experiments Feigelson found a temperature gradient that seemed to work.
BORIS FEIGELSON (WITH ENGLISH TRANSLATION): How we solved it is a top secret, but thankfully finally we managed to solve it.
NARRATOR: Feigelson had achieved his aim. His diamonds were now metal free, but the next problem he and all other diamond makers faced was that their diamonds were yellow. The colour is caused by nitrogen from the atmosphere getting into the presses.
DR MARK NEWTON (Oxford University): Any synthetic diamond you grow will have a lot of nitrogen in the structure and this nitrogen is incorporated as single substitutional nitrogen atoms, isolated nitrogen atoms dotted around the diamond lattice. The consequences of having nitrogen there is it gives the diamond colour, the nitrogen impurities set up an absorption of light and it gives the diamond a not very attractive brown colour.
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 colour.
MARK NEWTON: The nitrogen atoms have hopped around and formed aggregates where more than one nitrogen atom is bonded together. There's two atoms bond together in what's called the A aggregate, 4 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 a visible wavelength.
NARRATOR: If they were to make their yellow diamonds colourless the diamond makers had to find a way to replicate the passing of millions of years in nature in the laboratory.
BORIS FEIGELSON (WITH ENGLISH TRANSLATION): To get colourless diamonds what we had to do was get rid of the nitrogen which gives them their yellow colour.
NARRATOR: The clue for getting rid of the nitrogen came from an American experiment 20 years before. It suggested that the nitrogen atoms could be chemically attracted away from a growing diamond by using 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 colourless diamond.
BORIS FEIGELSON (WITH ENGLISH 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: In fact Feigelson has managed to remove the nitrogen and the metal inclusions. Although he can't make many, his diamonds can now be both clear and colourless. Colourless diamonds like these could turn into a nightmare for De Beers.
PAUL SPEAR: Clearly the, the near colourless diamond if there were no clues such as the presence of inclusions then a microscope is, is very little help to you.
NARRATOR: While Feigelson is 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. They 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 had to offer was skill, the science of making gem quality diamonds. Desperate for money to keep the Institute running they have been forced to look abroad. Eventually word of their achievements reached an American company. In return for the Institute's know-how the Americans have invested millions of dollars in a joint research project to make coloured synthetic diamonds a commercial reality.
CARTER CLARKE: Our 2 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 colour time after time. We have now accomplished that so we're now ready to go into the commercial side of this business. NARRATOR: Now they are packing up some of their presses to send to Clarke in America, the beginning of a new diamond production line, the first time that synthetic gem diamonds 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 8 milligrams per hour of growth which means we can produce a 1 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.
MARTIN RAPAPORT: A synthetic diamond by itself is no problem. As long as the industry maintains rules of detection & 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.
STEPHEN LUSSIER: And your consumer in the old days easily could tell an imitation from the real thing. Now it's a bit more tricky. De Beers's 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 the potential crisis of confidence caused by new synthetics undetectable under a microscope, De Beers have 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 machinery.
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 of 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 which discriminate synthetic from natural diamond using this equipment.
NARRATOR: After hundreds of experiments De Beers's 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 4 synthetic diamonds and on the right 4 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 4 synthetic diamonds are glowing very brightly under the action of this very hard ultraviolet light, but as the 4 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: De Beers believe that the cause of phosphorescence in synthetic diamonds can be traced to the way they grow. While natural diamonds have an octahedral structure because synthetics grow in an artificial environment they also form cube shaped sectors. It is this mixture of cubes and octahedral growth that causes synthetics to absorb ultraviolet light differently.
PAUL SPEAR: If we look at the, 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 growth 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 colourless synthetic diamond.
NARRATOR: Because of the way defects like nitrogen concentrate in these growth sectors light is held back and released slowly causing this unique phosphorescence. De Beers have incorporated these lessons into a sophisticated detection device 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, always trapped by the Diamond View.
NARRATOR: The Diamond View machine is only available to a few gem laboratories and not to the average dealer, but De Beers believe they have found the one feature of synthetic diamonds that proves they can't 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: De Beers say that they have defeated the diamond makers at an atomic level, but even this is being challenged. The diamond makers claim that their diamonds may not be detectable for ever.
CARTER CLARKE: When you send one of our diamonds to De Beers, right, the only way they can detect that, that this is not a natural diamond is really through phosphorescence. They take this and they put it in, they hit it with a UV light and after the UV light goes off this thing will phosphoresce for about 3-5 seconds. That is typical of a synthetic diamond versus a natural diamond. Something you would not do in a jewellery store, for example. However, we have a way to overcome that.
NARRATOR: Carter Clark has yet to prove he can overcome it, but it's clear that the scientists have been working hard to make it happen. Today 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.
DR YURI PAL'YANOV (RUSSIAN WITH ENGLISH TRANSLATION) (Russian Academy of Sciences): 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: These are not industrial grit diamonds, but minute diamonds made in the laboratory under conditions closer to nature than ever before. These scientists believe that before long they will work out how to grow these tiny diamonds into gems. Faced with the future threat of synthetic diamonds being imperceptible to the trade, De Beers are already preparing their 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 jeweller knows, De Beers has told them that this diamond is, is natural from as it, as it came out of the ground, created by nature billions of years ago and, and not one that popped out of a machine last Wednesday in Kansas City.
NARRATOR: Finally the science of diamond making has become so ingenious that even experienced dealers can't tell the difference between man-made and natural diamonds without the most sophisticated technology. For 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: In the future the consumer may well have that choice.
STEPHEN LUSSIER: I always think it's a bit like a masterpiece from Picasso and, and a copy. In the end one is worth $30 million and, and a magnificent treasure in the world and the other is a worthless copy.
CARTER CLARKE: We have asked many women whether they would prefer a 4 carat synthetic diamond or a 2 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 for ever, just as forever as any natural diamond is and maybe then some.
Source www.bbc.co.uk
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Well, let's make a cup of cappuccino coffee and enjoy your reading with this diamond jewelry article
TRACY HALL (General Electric, retired): 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 carbonised, it will turn to a graphitic-like material. So peanut butter to diamond.
DR ROBERT HAZEN (Carnegie Institute): I guess the question you've got to ask yourself is: is it possible for humans to synthesise diamonds till they're absolutely indistinguishable from a natural stone and I suppose the answer has to be yes.
NARRATOR (LINDSAY DUNCAN): There is something so special about diamonds and they are so valuable that people have always been prepared to go to the most extraordinary lengths to find them.
STEPHEN LUSSIER (Marketing Director, De Beers): 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 3 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: For hundreds of years people have bought into the mystique of diamonds and have been seduced by the hardness and brilliance that makes them so glamorous.
STEPHEN LUSSIER: The consumer actually wants a piece of forever. That's what a diamond is. It's a promise of forever.
NARRATOR: But how would we feel about the uniqueness of diamonds if it was possible to make one in a laboratory, just like the real thing, down to the nearest atom? In the last few years there has been a scientific race to do exactly this, to manufacture the perfect gem diamond.
DR BORIS FEIGELSON (RUSSIAN WITH ENGLISH TRANSLATION) (Diamond Scientist): Today the diamonds we produce are gem quality. They possess the same properties as natural real diamonds. They are exactly the same.
GENERAL CARTER CLARKE (Gemesis Corporation): Our diamond is so much cheaper to produce. It's more rare right now because we're not producing very many, but I don't think you could ever dig a natural diamond out of the ground, go through all the processes they have to have, for anywhere close to what we can make them for.
INTERVIEWER: How much can you make them for?
CARTER CLARKE: Less than $100.
NARRATOR: For hundreds of years people have tried to cash in by copying diamonds out of glass, paste and modern simulants like cubic zirconia, but these have none of the qualities of diamond because they are not made of the real thing. Fake diamonds can never equal nature because they are not made of the same unique material. In fact for centuries no-one knew what diamonds were made of. The only way to find out is to destroy one. In this lab a real diamond is being heated to over 1500 degrees Centigrade, then put immediately into liquid oxygen. The diamond burns away completely to leave: only carbon dioxide gas. There is just one material that reacts this way: pure carbon. Diamond is made out of pure carbon, but then so is graphite, the material we make pencils from. It's hard to imagine that this soft, dark substance is made out of the same thing as diamond.
DR 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 3 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 4 neighbours 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: The challenge for the diamond makers was to change the atomic structure of graphite, a soft and slippery substance, to diamond, the hardest, with a structure that refracts light in the most extraordinary way. No-one had got close until the 1950s. Nature's monopoly of the diamonds was challenged by the American engineering company General Electric. It was the beginning of the race to make diamonds. In the greatest secrecy, in Schenectady, New York GE started Project Super-pressure. Its aim was to make the world's first industrial diamonds with the same properties as natural diamonds. A young chemist called Tracy Hall was invited to join the team.
DR TRACY HALL (General Electric, retired): 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 and there's only one man we want, so I was the only one that held up my hand so I got the job.
NARRATOR: Then Hall was joined by a physicist, Herbert Strong.
DR HERBERT STRONG (General Electric, retired): And he said how would you fellows like to try to make diamonds. Huh, yeah, sure. I was enthusiastic about it, no thought of failure at all. No of course not.
NARRATOR: The diamond makers' first challenge was to break down the carbon atoms in graphite. Their problem was that graphite 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 'cos each carbon atom has 4 electrons that it wants to share with its adjacent atoms in covalent bonding so in graphite there are 3 adjacent carbons to every individual carbon sharing 3 electrons and then the fourth electron resonates within these ring-like structures adding additional strength to the graphite layer.
NARRATOR: The only clue the GE team had to turn graphite into diamond came from nature. Geologists knew that hypersonic explosions had brought diamonds to the surface as passengers in molten rock, that somehow 200 miles under the earth nature had turned graphite into diamond, that diamonds are found in the necks of extinct volcanoes.
ROBERT HAZEN: As a result, geologists found out that diamonds had to be high pressure materials, they were high pressure minerals and that was the key to diamond synthesis.
NARRATOR: The GE team had to find a way to replicate in minutes millions of years of pressure from a rock column 200 miles deep and the vast temperatures of the Earth's mantle. Only then might they be able to break down the atoms of graphite and reform them into diamond. But they had little idea what the right combination of temperature and pressure should be.
HERBERT STRONG: Just having a sense of how nature works you realise it was going to have to be way up here at very high temperature to get the atoms loose from graphite so they could go to diamond. It would have to be over 1,000 degrees Centigrade, probably higher than that. That was a guess and the pressure then would have to be up or diamond would be stable at that high temperature, it wouldn't go back to graphite.
NARRATOR: GE spent millions on diamond presses capable of focusing huge pressures and temperatures on the graphite capsule, 60,000 atmospheres and 3,000 degrees Centigrade, but still the graphite wouldn't turn to diamond. They had learned a crucial lesson.
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 4 years of broken presses Project Super-pressure was in trouble. The team knew that they had to find a way of making diamonds at lower temperatures and pressures or the project would be cancelled, but before they could make diamonds they had to find a way to break down the atomic structure of graphite. They had one more clue. Diamond may need high temperatures and pressures to form, but in one way it is no different from any other crystal, like ice. The individual atoms form together out of liquid solution.
HERBERT STRONG: What seemed logical to me was to dissolve the, the graphite into a solvent so as to get the carbon atoms loose and make 'em available for forming diamond. Well what is the solvent for carbon?
TRACY HALL: Well I had read that some tiny diamonds had been found in the meteorite crater that was in Arizona.
NARRATOR: In the 1950s it was discovered that this crater was made by a meteorite. When geologists looked at the meteorite diamonds they realised that they had been formed on impact.
DR SARAH RUSSELL (Natural History Museum): When the asteroid hit the Earth there 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: The GE team found another clue in that meteorite, something they thought must have helped form the diamonds. The diamonds were surrounded by metal.
SARAH RUSSELL: I've got a piece of the meteorite here and you can see this dark coloured 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 team were looking for. They hoped that this particular metal, called troilite when heated into a liquid state would act as a solvent to break down the carbon atoms in graphite. They tried adding some troilite in their growth capsule.
TRACY HALL: It was a wintery 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 2,600 degrees Fahrenheit.
NARRATOR: They hoped in this experiment that the carbon atoms in the graphite would dissolve into the molten troilite and then, when they had reached a high enough pressure and temperature, would crystallise as diamond.
HERBERT STRONG: We were in the hunch stage and my hunch was that when you're in the diamonds pressure region and you'd 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, 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 hoped that this would be enough for diamonds to form. Just as they had dozens of times in the past 5 years they broke open the capsule.
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 the gleam of the sun shining on these things and I, I, you know, twiddled 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, 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.
TRACY HALL: It was front page news in almost every newspaper in the United States overseas too, also and the people in the diamond people in, where would they have been, Antwerp, they were scared stiff.
NARRATOR: The diamond market had no reason to panic. Although the diamonds General Electric made had the same atomic structure as natural diamonds they were like grains of sand, but they revolutionised industry because just like natural diamonds, they were the hardest material in the world and they could cut through anything. But these tiny pieces of grit could never set a girl's heart racing. The science just wasn't there to make them sparkle. But for years no-one knew how to turn industrial diamonds into these. It takes millions of years for nature to grow gem diamonds and that is what makes them special.
STEPHEN LUSSIER: Women truly desire diamonds. It helps them sparkle brilliantly when, when they're wearing it. They like that feeling of wearing diamonds. The task of marketing really is only to help them achieve their desire of getting one.
NARRATOR: De Beers is the diamond business and this building is where they control the world diamond trade. By buying up most of the world's uncut diamonds the company can regulate supply to select dealers, increasing it in good years and reducing it in bad to keep prices high. Every year from this building £3 billion's worth of rough diamonds are distributed around the world for cutting and polishing. It is a cartel that has been built on the claim that diamonds have a unique appeal to women.
STEPHEN LUSSIER: The consumer actually wants a symbolic product and I think if the product is it forever there's no 3 billion years old. If it did just come out of a, you know, popped out of a machine 3 days ago it can't possibly have that symbolism.
NARRATOR: The beauty, glamour and cost of diamonds presented a new challenge for the diamond makers, to synthesise a gem quality diamond just like nature but in a fraction of the time. Now there are places in the world where nature's monopoly on gem diamonds is being challenged. Hidden behind the Iron Curtain industrial diamonds have been produced for years, but in a new Russia, scientists are becoming more ambitious.
In July 1993 Boris Feigelson set up his own lab in rooms rented from the Institute of the Blind. His plan was to grow industrial diamonds so they became as big as gems, but this required expensive high pressure equipment and with little money everything he did had to be built from scratch. To make large gem quality diamonds Feigelson had to find a way to make the diamond grit grow, but this meant running his presses at high temperatures and pressures for days. At the beginning this was impossible.
BORIS FEIGELSON (WITH ENGLISH 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 down from the metal solvent to the cooler temperatures at the bottom where they latch on to the seed. If the process is regulated carefully the seed grows. After 2 days of high temperature and pressure, these machines can each produce a one carat diamond, large, but flawed, with tell-tale signs of manufacture.
Boris Feigelson was not the only one trying to make gem diamonds. There are at least 5 labs spread around the old Soviet Union, from Moscow to Siberia, and they have all learnt the same basic skills of diamond synthesis. Even the earliest flawed diamonds the Russians made were enough to set the alarm bells ringing at De Beers. In fact De Beers had been taking this threat seriously for years. They have been growing diamonds in this laboratory to see if their own scientists can distinguish between synthetic and natural diamonds.
DR ROBBIE BURNS (De Beers): 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 6 weeks and they are 25 carats in weight each grown 4 at a time, so we're actually quite proud of this.
NARRATOR: The diamonds grown in Johannesburg come here to a research laboratory outside London. This building is the centre of the gem defence programme where they spend £3 million a year in a race with the diamond makers to maintain the confidence of their customers. 100 staff are employed to identify the tiniest difference between the new synthetics and natural diamonds. As the synthetics have become ever more perfect, De Beers have had to invent new methods of detection.
DR PAUL SPEAR (De Beers): De Beers's aim is to instil 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, in the trade and the vast majority of those, of course, are the yellow brown material. There are very few near colour stones, 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: While De Beers deny the diamond makers are a serious threat the trade is already feeling the heat. This is the world's largest gem fair. Thousands of diamond dealers selling their wares to jewellers' shops around the world, a £30 billion a year industry. It is a business that the diamond makers want a part of. Alex Grizenko is a middle man for other Russian diamond makers. He is here to sell the idea that man-made diamonds are intrinsically the same as the real thing.
ALEX GRIZENKO (Diamond Trader): You think on a philosophical level 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. Now as we know there are many simulants on the market. They're cubic zirconi has been around for many years. A new simulant called moissonite has entered the marketplace, but these are all pretending to be carbon. They're not carbon, and here the diamonds.
NARRATOR: The potential payout of synthetic diamonds entering the market place for the first time has already got the trade worrying about a doomsday scenario, the worst imaginable threat to the natural diamond business.
VOICE: You've hit the jackpot!
MARTIN RAPAPORT (Diamond Trader): 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 gives us the ability to make a synthetic diamond that no-one knows is synthetic.
NARRATOR: The trade may believe that diamond makers are far from producing undetectable synthetics, but behind the scenes the scientists have been working hard to rid their gems of the telltale signs of manufacture. The biggest problems were bits of metal that got trapped in the growing diamonds. They came from the metal solvent used to dissolve the graphite.
PAUL SPEAR: This diamond contains quite a number of inclusions. I'll zoom in on one of those and you can see how this, 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 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 are keen to spread to gemologists around the world. In gem testing centres classes are taught in synthetic diamond detection using similar diamonds supplied by De Beers.
LECTURER: In some cases synthetic diamonds can be attracted to a magnet as a result of the presence of these metallic inclusions…
NARRATOR: For these gemologists identifying synthetic diamonds with metal inclusions is as simple as putting them under a microscope.
LECTURER: The next slide please.
NARRATOR: To stop metal from ruining their diamonds the Russians had to control the atomic growth of the crystals in a far more exacting way. They had to prevent the metal from joining an interrupted flow of carbon atoms as they formed the diamond. They had to keep the flow of carbon so perfectly constant that the metal couldn't get near the growing diamond and the way to do this was to control the temperature within the growth cell in the most minute way.
BORIS FEIGELSON (WITH ENGLISH TRANSLATION): It was clear to us that we had to refine the chemistry and stabilise the heating process as much as possible and that would control the temperature.
NARRATOR: Feigelson adapted and refined an old idea. By minutely controlling the temperature gradient, hotter at the top to dissolve the carbon atoms into the metal solution and cooler around the diamond seed, Feigelson could ensure the carbon came out of the solution in a constant flow preventing the metal from reaching the diamond seed. After hundreds of experiments Feigelson found a temperature gradient that seemed to work.
BORIS FEIGELSON (WITH ENGLISH TRANSLATION): How we solved it is a top secret, but thankfully finally we managed to solve it.
NARRATOR: Feigelson had achieved his aim. His diamonds were now metal free, but the next problem he and all other diamond makers faced was that their diamonds were yellow. The colour is caused by nitrogen from the atmosphere getting into the presses.
DR MARK NEWTON (Oxford University): Any synthetic diamond you grow will have a lot of nitrogen in the structure and this nitrogen is incorporated as single substitutional nitrogen atoms, isolated nitrogen atoms dotted around the diamond lattice. The consequences of having nitrogen there is it gives the diamond colour, the nitrogen impurities set up an absorption of light and it gives the diamond a not very attractive brown colour.
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 colour.
MARK NEWTON: The nitrogen atoms have hopped around and formed aggregates where more than one nitrogen atom is bonded together. There's two atoms bond together in what's called the A aggregate, 4 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 a visible wavelength.
NARRATOR: If they were to make their yellow diamonds colourless the diamond makers had to find a way to replicate the passing of millions of years in nature in the laboratory.
BORIS FEIGELSON (WITH ENGLISH TRANSLATION): To get colourless diamonds what we had to do was get rid of the nitrogen which gives them their yellow colour.
NARRATOR: The clue for getting rid of the nitrogen came from an American experiment 20 years before. It suggested that the nitrogen atoms could be chemically attracted away from a growing diamond by using 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 colourless diamond.
BORIS FEIGELSON (WITH ENGLISH 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: In fact Feigelson has managed to remove the nitrogen and the metal inclusions. Although he can't make many, his diamonds can now be both clear and colourless. Colourless diamonds like these could turn into a nightmare for De Beers.
PAUL SPEAR: Clearly the, the near colourless diamond if there were no clues such as the presence of inclusions then a microscope is, is very little help to you.
NARRATOR: While Feigelson is 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. They 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 had to offer was skill, the science of making gem quality diamonds. Desperate for money to keep the Institute running they have been forced to look abroad. Eventually word of their achievements reached an American company. In return for the Institute's know-how the Americans have invested millions of dollars in a joint research project to make coloured synthetic diamonds a commercial reality.
CARTER CLARKE: Our 2 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 colour time after time. We have now accomplished that so we're now ready to go into the commercial side of this business. NARRATOR: Now they are packing up some of their presses to send to Clarke in America, the beginning of a new diamond production line, the first time that synthetic gem diamonds 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 8 milligrams per hour of growth which means we can produce a 1 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.
MARTIN RAPAPORT: A synthetic diamond by itself is no problem. As long as the industry maintains rules of detection & 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.
STEPHEN LUSSIER: And your consumer in the old days easily could tell an imitation from the real thing. Now it's a bit more tricky. De Beers's 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 the potential crisis of confidence caused by new synthetics undetectable under a microscope, De Beers have 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 machinery.
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 of 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 which discriminate synthetic from natural diamond using this equipment.
NARRATOR: After hundreds of experiments De Beers's 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 4 synthetic diamonds and on the right 4 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 4 synthetic diamonds are glowing very brightly under the action of this very hard ultraviolet light, but as the 4 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: De Beers believe that the cause of phosphorescence in synthetic diamonds can be traced to the way they grow. While natural diamonds have an octahedral structure because synthetics grow in an artificial environment they also form cube shaped sectors. It is this mixture of cubes and octahedral growth that causes synthetics to absorb ultraviolet light differently.
PAUL SPEAR: If we look at the, 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 growth 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 colourless synthetic diamond.
NARRATOR: Because of the way defects like nitrogen concentrate in these growth sectors light is held back and released slowly causing this unique phosphorescence. De Beers have incorporated these lessons into a sophisticated detection device 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, always trapped by the Diamond View.
NARRATOR: The Diamond View machine is only available to a few gem laboratories and not to the average dealer, but De Beers believe they have found the one feature of synthetic diamonds that proves they can't 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: De Beers say that they have defeated the diamond makers at an atomic level, but even this is being challenged. The diamond makers claim that their diamonds may not be detectable for ever.
CARTER CLARKE: When you send one of our diamonds to De Beers, right, the only way they can detect that, that this is not a natural diamond is really through phosphorescence. They take this and they put it in, they hit it with a UV light and after the UV light goes off this thing will phosphoresce for about 3-5 seconds. That is typical of a synthetic diamond versus a natural diamond. Something you would not do in a jewellery store, for example. However, we have a way to overcome that.
NARRATOR: Carter Clark has yet to prove he can overcome it, but it's clear that the scientists have been working hard to make it happen. Today 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.
DR YURI PAL'YANOV (RUSSIAN WITH ENGLISH TRANSLATION) (Russian Academy of Sciences): 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: These are not industrial grit diamonds, but minute diamonds made in the laboratory under conditions closer to nature than ever before. These scientists believe that before long they will work out how to grow these tiny diamonds into gems. Faced with the future threat of synthetic diamonds being imperceptible to the trade, De Beers are already preparing their 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 jeweller knows, De Beers has told them that this diamond is, is natural from as it, as it came out of the ground, created by nature billions of years ago and, and not one that popped out of a machine last Wednesday in Kansas City.
NARRATOR: Finally the science of diamond making has become so ingenious that even experienced dealers can't tell the difference between man-made and natural diamonds without the most sophisticated technology. For 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: In the future the consumer may well have that choice.
STEPHEN LUSSIER: I always think it's a bit like a masterpiece from Picasso and, and a copy. In the end one is worth $30 million and, and a magnificent treasure in the world and the other is a worthless copy.
CARTER CLARKE: We have asked many women whether they would prefer a 4 carat synthetic diamond or a 2 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 for ever, just as forever as any natural diamond is and maybe then some.
Source www.bbc.co.uk
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