NationMaster - Encyclopedia: Synthetic diamond

Synthetic diamond, also called lab-created, manufactured, "lab-grown" or cultured diamond is a term used to describe diamond (the tetrahedral carbon allotrope) which has been produced by a technological process, as opposed to natural diamond, which is produced by geological processes. Synthetic diamond is not the same as Diamond-like Carbon, DLC, which is amorphous hard carbon, or diamond simulants, which are made of other materials such as cubic zirconia or silicon carbide. The properties of synthetic diamond depend on the manufacturing process used to produce it, and can be inferior, similar or superior to those of natural diamond.^[1] Because it can be made for less than it costs to mine natural diamond, synthetic diamond is used in many industrial applications. Reduced costs and the ability to engineer its physical and electrical properties give synthetic diamond the potential to become a disruptive technology in many areas such as electronics and medicine. Image File history File links Metadata Size of this preview: 800 Ã— 507 pixelsFull resolution (1474 Ã— 934 pixel, file size: 335 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... Image File history File links Metadata Size of this preview: 800 Ã— 507 pixelsFull resolution (1474 Ã— 934 pixel, file size: 335 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... Chemical vapor deposition of diamond is a method of producing synthetic diamond by creating the circumstances necessary for carbon atoms in a gas to settle on a substrate in crystalline form. ... This article is about the mineral. ... This article or section does not cite any references or sources. ... By the mid 20th century humans had achieved a mastery of technology sufficient to leave the surface of the Earth for the first time and explore space. ... This article includes a list of works cited but its sources remain unclear because it lacks in-text citations. ... Diamond-like carbon (DLC) is an umbrella term that refers to 7 forms[1] of amorphous carbon materials that display some of the unique properties of natural diamond. ... Due to its low cost and close visual likeness to diamond, cubic zirconia has remained the most gemologically and economically important diamond simulant since 1976. ... A round brilliant-cut cubic zirconia Cubic zirconia (or CZ), the cubic crystalline form of zirconium dioxide (ZrO2), is a mineral that is widely synthesized for use as a diamond simulant. ... Except where noted otherwise, data are given for materials in their standard state (at 25 Â°C, 100 kPa) Infobox disclaimer and references Silicon carbide (SiC) is a ceramic compound of silicon and carbon that is manufactured on a large scale for use mainly as an abrasive but also occurs in... The Materials Science Tetrahedron, which often also includes Characterization at the center Materials science or Materials Engineering is an interdisciplinary field involving the properties of matter and its applications to various areas of science and engineering. ... A disruptive technology or disruptive innovation is a technological innovation, product, or service that eventually overturns the existing dominant technology or product in the market. ...

History

The idea of making less expensive, gem-quality diamonds synthetically is not a new one. H. G. Wells described the concept in his short story "The Diamond Maker," published in 1911 ^[2]. In Capital Karl Marx commented, "If we could succeed, at a small expenditure of labour, in converting carbon into diamonds, their value might fall below that of bricks". ^[3] Herbert George Wells (September 21, 1866 â€“ August 13, 1946), better known as H. G. Wells, was an English writer best known for such science fiction novels as The Time Machine, The War of the Worlds, The Invisible Man, The First Men in the Moon and The Island of Doctor Moreau. ... Karl Heinrich Marx (May 5, 1818 â€“ March 14, 1883) was a 19th century philosopher, political economist, and revolutionary. ...

Ever since the discovery that diamond was pure carbon in 1797 many attempts were made to alter the cheaper forms of carbon - generally with little success. One of the early successes reported in the field was by Ferdinand Frédéric Henri Moissan in 1893. His method involved heating charcoal at up to 4000 °C with iron in a carbon crucible in an electric furnace, in which an electric arc was struck between carbon rods inside blocks of lime. The molten iron was then rapidly cooled by immersion in water. The contraction generated by the cooling supposedly produced the high pressure required to transform graphite into diamond. Moissan published his work in a series of articles in the 1890's. Image File history File links Wikisource-logo. ... The original Wikisource logo. ... Ferdinand Frederick Henri Moissan (September 28, 1852 â€“ February 20, 1907) was a French chemist who won the 1906 Nobel Prize in Chemistry for his work in isolating fluorine from its compounds. ... Charcoal is the blackish residue consisting of impure carbon obtained by removing water and other volatile constituents from animal and vegetation substances. ... For other uses, see Carbon (disambiguation). ... This article or section does not adequately cite its references or sources. ...

Many other scientists tried to replicate his experiments. Sir William Crookes claimed success in 1909. Ruff claimed in 1917 to have reproduced diamonds up to 7 mm in diameter, but later retracted his claims. ^[4] In 1926, Dr. Willard Hershey of McPherson College read journal articles about Moissan's and Ruff's experiments and replicated their work, producing a synthetic diamond. That diamond is on display today in Kansas at the McPherson Museum. ^[5] Despite the claims of Moissan, Ruff, and Hershey, many other experimenters had enormous difficulty in creating the required temperatures and pressure with similar equipment, leading some to contend that the early successes were the result of seeding by good-willed co-workers. ^[6] Sir William Crookes, OM, FRS (17 June 1832 â€“ 4 April 1919) was an English chemist and physicist. ... Chartered in 1887 by leaders of the Church of the Brethren, McPherson College, Kansas, has a 119 year history of providing classic liberal arts and career-oriented education shaped by the essential values of its founding denomination. ... The McPherson Museum of McPherson, Kansas, is a local history museum that preserves the historical and cultural heritage of the McPherson community. ...

The most definitive duplication attempts ^[4] were performed by Sir Charles Algernon Parsons. He devoted 30 years and a considerable part of his fortune to reproduce many of the experiments of Moissan as well as those of Hannay but also adapted processes of his own. He wrote a number of articles -- one of the earliest on HPHT diamonds -- in which he claimed to have produced small diamonds. ^[7]. However in 1928 he authorized C.H Desch to publish an article in which he stated his belief that no synthetic diamonds (including those of Moisan and others) had been produced up to that date. In fact he found that most diamonds produced so far were more likely than not synthetic Spinel. ^[4] Charles Algernon Parsons Compund Steam Turbine, circa 1887 Sir Charles Algernon Parsons, O.M. (June 13, 1854 â€“ February 11, 1931) was a British engineer, best known for his invention of the steam turbine. ... The spinels are any of a class of minerals which crystallize in the isometric system with an octahedral habit. ...

The GE Diamond Project

The first person who grew a synthetic diamond according to a reproducable, verifiable and witnessed process was Howard Tracy Hall while working for General Electric in 1954. He received a gold medal of the American Chemical Society in 1972 for his work. ^[4] In 1941 an agreement was made between General Electric, Norton and Carborundum to further develop diamond synthesis. However this project soon thereafter ended because of the Second World War. They were able to heat Carbon to about 3000 °C (5432 °F) under a pressure of half a million psi, for a few seconds. ^[4] â€œGEâ€ redirects here. ... â€œGEâ€ redirects here. ... Mushroom cloud from the nuclear explosion over Nagasaki rising 18 km into the air. ...

In 1951 the project was resumed at the Schenectady Laboratories of GE and a high pressure diamond group was formed with F.P. Bundy, H.M. Strong, and shortly afterwards joined by H. T. Hall and others. Following on the work done by Percy Bridgman (who received a Nobel prize for his work in 1946) Bridgman's Anvils were further improved first by Bundy and Strong and later by Hall. The GE team used a tungsten carbide "anvil" within a hydraulic press to squeeze the carbonaceous sample held in a catlinite container, the finished grit being squeezed out of the container through a gasket. It was believed that on occasion a diamond was produced, but since experiments could not be reproduced, such claims could not be maintained. ^[4] Percy Williams Bridgman (April 21, 1882 Cambridge, Massachusetts â€“ August 20, 1961) was an American physicist who won the 1946 Nobel Prize in Physics for his work on the physics of high pressures. ... Monotungsten carbide, WC, or Ditungsten Carbide, W2C, is a chemical compound containing tungsten and carbon, similar to titanium carbide. ...

Finally Tracy Hall managed the first commercially successful synthesis of diamond on December 16, 1954 (announced on February 15, 1955). Hall's breakthrough was using an elegant "belt" press apparatus which raised the achievable pressure from 6 to 18 GPa and the temperature to 5000 °C, using a pyrophyllite container, and having the graphite dissolved within molten nickel, cobalt or iron, a "solvent-catalyst". Hall was able to have co-workers replicate his work and the discovery was published in Nature. The largest diamond produced by Hall was 150 micrometres across, clearly unsuitable for ornamentation but very useful in industrial abrasives. ^[4] This gave rise to an industrial diamond industry that was for decades represented by two main players: GE Superabrasives and De Beers Industrial Diamonds. Tracy Hall (1919-) is an American physical chemist who first synthesized diamond using a press of his own design. ... is the 350th day of the year (351st in leap years) in the Gregorian calendar. ... Year 1954 (MCMLIV) was a common year (link will display full calendar) of the Gregorian calendar. ... Pyrophyllite is a mineral species belonging to the clay family and composed of hydrous aluminium silicate HAl (SiOf)2. ... Nature is a prominent scientific journal, first published on 4 November 1869. ... The De Beers Group is a Johannesburg- and London-based diamond mining and trading corporation. ...

Another successful diamond synthesis was produced on February 16, 1953 in Stockholm, Sweden by the QUINTUS project of ASEA (Allemanna Svenska Elektriska Aktiebolaget), Sweden's major electrical manufacturing company using a bulky split sphere apparatus designed by Baltzar von Platen and the young engineer Anders Kämpe (1928–1984). Pressure was maintained within the device at an estimated 83,000 atmospheres (8.4 GPa) for an hour. A few small crystals were produced, but not of gem quality or size. The work was not reported until the 1980s. is the 47th day of the year in the Gregorian calendar. ... Year 1953 (MCMLIII) was a common year starting on Thursday (link will display full calendar) of the Gregorian calendar. ... For other uses, see Stockholm (disambiguation). ... ASEA (AllmÃ¤nna Svenska Elektriska Aktiebolaget) was a Swedish industry company. ... Baltzar von Platen ( 1898- 1984) together with Carl Munters was the inventor of the gas absorption refrigerator in 1922 while they were both Swedish engineering students at the Royal Institute of Technology in Stockholm, Sweden. ... High pressure science and engineering is studying the effects of high pressure on materials and the design and construction of devices, such as a diamond anvil cell, which can create high pressure. ...

During the 1980s a new competitor emerged in Korea named Iljin Diamond, followed later by hundreds of Chinese entrants. Iljin Diamond allegedly accomplished this by misappropriating trade secrets from GE via a Korean former GE employee in 1988 (General Electric v. Sung, 843 F. Supp. 776). In 2003 GE sold GE Superabrasives to a private equity firm called Littlejohn and it was renamed to Diamond Innovations. Littlejohn sold Diamond Innovations to Sandvik in January of 2007. Also, in 2002, De Beers Industrial Diamonds rebranded to Element Six and is operating as an independent company from De Beers. Many more companies have become important players in the industrial diamond market. The main ones are Sumitomo Electric Hardmetal, US Synthetic, Smith Megadiamond and Novatek. Some smaller companies have signaled their intent to enter the market for gems using synthetic diamond. These are Adia Diamonds, Apollo Diamond, Gemesis and Tairus and a German company("SEDKRIST). As of 2006, the industrial diamond industry is an annual US$1 billion market, producing some 3 billion carats, or 600 metric tons, of synthetic diamond. This should be put in comparison with the 130 million carats (26 metric tons) mined annually for gem purposes. Ge may refer to: GÃª, a group of indigenous Brazilian tribes and their Ge languages Ge (Cyrillic) (Ð“, Ð³), a letter of the Cyrillic alphabet Ge with upturn (Ò, Ò‘), a letter of the Ukrainian alphabet Nikolai Ge, a Russian painter GÄ“, an ancient Chinese dagger-axe Ge (genus), a genus of butterflies Also... Littlejohn may refer to: // Adrian Littlejohn (b. ... ... De Beers, founded in South Africa by Cecil Rhodes, comprises companies involved in rough diamond exploration, diamond mining and diamond trading. ... Wikipedia does not have an article with this exact name. ... Apollo Diamond, based in Boston, produces nearly flawless single crystal diamond wafers and crystals for the optoelectronics, nanotechnology, and consumer gem markets. ... The Gemesis Corporation is a privately-held company founded by Carter Clarke in Sarasota, Florida, United States. ... Tairus (Russian: Ð¢Ð°Ð¹Ñ€ÑƒÑ, a portmanteau of Ð¢Ð°Ð¹ÑÐºÐ¾ (Thai) and Ð ÑƒÑÑÐºÐ¸Ð¹ (Russian)) is a synthetic gemstone manufacturer. ... USD redirects here. ... A tonne (also called metric ton) is a non-SI unit of mass, accepted for use with SI, defined as: 1 tonne = 103 kg (= 106 g). ...

Synthetic gem-quality diamond crystals were first produced in 1970 (reported in 1971) again by GE. Hall had continued to work for GE, developing the tetrahedral press with four anvils. Large crystals need to grow very slowly under extremely tightly controlled conditions. The first successes used a pyrophyllite tube seeded at each end with thin pieces of diamond and with the graphite feed material placed in the centre, the metal solvent, nickel, was placed between the graphite and the seeds. The container was heated and the pressure raised to around 55,000 atmospheres. The crystal grow as they flow from the centre to the ends of the tube, the longer the process is extended the larger the crystals - initially a week-long growth process produced gem-quality stones of around 5 mm and one carat. The graphite feed was soon replaced by diamond grit, as there was almost no change in material volume so the process was easier to control.

The first gem-quality stones were predominantly cubic and octahedral in form and, due to contamination with nitrogen, always yellow to brown in color. Inclusions were common, especially "plate-like" ones from the nickel. Removing all nitrogen from the process by adding aluminium or titantium produced a colourless 'white' stone, while removing the nitrogen and adding boron produced a blue. However removing nitrogen slows the growth process and impairs the crystals properties, so most stones are still yellow. In terms of physical properties the GE stones were not quite identical to natural stones. The colourless stones were semi-conductors and fluoresed and phosphoresed strongly under SWUV but were inert under LWUV - in nature only blue stones should do this. All the GE stones also showed a strong yellow fluorescence under X-rays. De Beers Diamond Research Laboratory has since grown stones of up to 11 carats, but most stones are around 1 to 1.5 carats for economic reasons, especially with the spread of the Russian BARS apparatus since the 1980s. General Name, Symbol, Number boron, B, 5 Chemical series metalloids Group, Period, Block 13, 2, p Appearance black/brown Standard atomic weight 10. ...

The GE method is called HPHT (High Pressure, High Temperature), but there is another method. Following on from work by John Angus and Boris Spitsyn researchers at the National Institute for Research in Inorganic Materials in Tsukuba produced diamonds at less than one atmosphere of pressure and only 800 °C through CVD, Chemical Vapour Deposition. The Japanese had begun their research in 1974 and reported their success in 1981.

The Japanese passed a mixture of carbon-containing gas (methane in their case) and hydrogen into a quartz tube at a pressure of 0.05 atmospheres. Using microwaves the mixture was heated to 800 °C, disassociating both the methane and hydrogen into elemental forms. The carbon is deposited on a substrate, the majority as graphite but a very small proportion as diamond crystal. the graphite is 'removed' by the hydrogen leaving a thin layer of diamond, initially the layer was around 25μm in thickness.

Properties of synthetic diamond

The gem diamond most people are aware of is just one of many different forms that diamond can take. Natural gem diamond is a single crystal diamond with low levels of impurities. This homogeneity is what allows it to be clear, while its material properties and hardness are what make it a popular gemstone. Most natural diamond removed from the earth's crust does not have the high purity or high crystallinity necessary to be a quality gemstone. Following are some important properties by which various types of diamond are described.

Crystallinity refers to the degree of structural order in a solid. ... Look up hardness in Wiktionary, the free dictionary. ...

Manufacturing technologies

There are two main methods to produce synthetic diamond. The original method is High Pressure High Temperature (HPHT) and is still the most widely used method because of its relative low cost. It uses large presses that can weigh a couple of hundred tons to produce a pressure of 5 GPa at 1,500 degrees Celsius to reproduce the conditions that create natural diamond inside the Earth. The second method, using chemical vapor deposition or CVD, was invented in the 1980s, and is basically a method creating a carbon plasma on top of a substrate onto which the carbon atoms deposit to form diamond. For other uses, see Plasma. ...

High Pressure, High Temperature (HPHT)

There are two main press designs used to supply the pressure and temperature necessary to produce synthetic diamond. These basic designs are the belt press and the cubic press. There are a number of other designs, but none of them are used for industrial scale manufacturing.

The original GE invention by H. Tracy Hall, uses the belt press, wherein upper and lower anvils supply the pressure load and heating current to a cylindrical volume. This internal pressure is confined radially by a belt of pre-stressed steel bands. A variation of the belt press uses hydraulic pressure to confine the internal pressure, rather than steel belts. Belt presses are still used today by the major manufacturers at a much larger scale than the original designs.

The second type of press design is the cubic press. A cubic press has six anvils which provide pressure simultaneously onto all faces of a cube-shaped volume. The first multi-anvil press design was actually a tetrahedral press, using only four anvils to converge upon a tetrahedron-shaped volume. The cubic press was created shortly thereafter to increase the pressurized volume. A cubic press is typically smaller than a belt press and can achieve the pressure and temperature necessary to create synthetic diamond faster. However, cubic presses cannot be easily scaled up to larger volumes. To illustrate, one could increase the pressurized volume by either increasing the size of the anvils, thereby increasing by a great factor the amount of force needed on the anvils to achieve a similar pressurization, or by decreasing the surface area to volume ratio of the pressurized volume by using more anvils to converge upon a different platonic solid (such as a dodecahedron), but such a press would be unnecessarily complex and not easily manufacturable. In geometry, a Platonic solid is a convex regular polyhedron. ...

Chemical Vapor Deposition of Diamond (CVD)

Main article Chemical vapor deposition of diamond Chemical vapor deposition of diamond is a method of producing synthetic diamond by creating the circumstances necessary for carbon atoms in a gas to settle on a substrate in crystalline form. ...

Chemical vapor deposition of diamond is a method of growing diamond by creating the environment and circumstances necessary for carbon atoms in a gas to settle on a diamond substrate in diamond crystalline form. This method of diamond growth has been the subject of a great deal of research since the early 1980s, and since 2003^[8] Apollo Diamond has been producing gem-quality diamonds. As of 2007, they produce colourless, near-colourless, cognac and salmon-coloured diamonds.^[9] Apollo Diamond, based in Boston, produces nearly flawless single crystal diamond wafers and crystals for the optoelectronics, nanotechnology, and consumer gem markets. ... 2007 is a common year starting on Monday of the Gregorian calendar. ...

Applications

Given the extraordinary set of physical properties diamond exhibits, diamond has and could have a wide-ranging impact in many fields.

Wear Resistance

Diamonds have long been used in machining tools, especially when machining non-ferrous alloys. While natural diamond is certainly still used for this, the amount of synthetic diamond is far greater. The most common usage of diamond in cutting tools is done by distributing micrometer-sized diamond grains in a metal matrix (usually cobalt), hardening it and then sintering it onto the tool. This is typically referred to in industry as “PCD” diamond. PCD tipped tools are often used in mining and in the automotive aluminum cutting industry. This article or section does not cite its references or sources. ...

For the past fifteen years work has also been done in the hope of using CVD diamond growth to coat tools with diamond,^[10] and though the work still shows promise it has not significantly displaced traditional PCD tools.

Electronics

CVD diamond also has applications in electronics. Conductive diamond has been demonstrated as a useful electrode under many circumstances.^[11] For example, University of Wisconsin-Madison chemistry professor Robert Hamers has developed photochemical methods for covalently linking DNA to the surface of polycrystalline diamond films produced through CVD. Also, the diamonds have been shown to detect redox reactions that can't ordinarily be studied and in some cases degrade redox-reactive organic contaminants in water supplies. Because diamond is almost completely chemically inert it can be used as an electrode under conditions that would destroy traditional materials. For such reasons waste water treatment of organic effluents^[12] as well as production of strong oxidants have been published.^[13] There are already a number of companies producing diamond electrodes. University of Wisconsin redirects here. ... The structure of part of a DNA double helix Deoxyribonucleic acid, or DNA, is a nucleic acid molecule that contains the genetic instructions used in the development and functioning of all known living organisms. ... Illustration of a redox reaction Redox (shorthand for oxidation/reduction reaction) describes all chemical reactions in which atoms have their oxidation number (oxidation state) changed. ...

Diamond has shown great promise as a potential radiation detection device. Diamond has a similar density to that of soft tissue, is radiation hard and has a wide bandgap. These qualities suggest it has potential to be an excellent radiation detection material, and it has already been employed in some applications, such as the BABAR detector at Stanford.^[14] A semiconductor particle detector is a device that uses a semiconductor (usually silicon) to detect the passage of charged particles. ...

Diamond also has potential uses as a semiconductor.^[15] This is because the diamonds can be "doped" with impurities like boron and phosphorus. Since these elements contain one more or one less valence electron than carbon, they turn the diamonds into p-type or n-type semiconductors. There are also studies being conducted about impregnating boron-doped CVD diamonds with deuterium to produce n-type semiconducting diamonds. Diamond transistors are functional to temperatures many times that of silicon and are resistant to chemical and radioactive damage. While no diamond transistors have yet been successfully integrated into commercial electronics, they show promise for use in exceptionally high power situations and hostile environments. A semiconductor is a solid whose electrical conductivity is in between that of a conductor and that of an insulator, and can be controlled over a wide range, either permanently or dynamically. ... In semiconductor production, doping refers to the process of intentionally introducing impurities into an intrinsic semiconductor in order to change its electrical properties. ... General Name, Symbol, Number boron, B, 5 Chemical series metalloids Group, Period, Block 13, 2, p Appearance black/brown Standard atomic weight 10. ... General Name, symbol, number phosphorus, P, 15 Chemical series nonmetals Group, period, block 15, 3, p Appearance waxy white/ red/ black/ colorless Standard atomic weight 30. ... For other uses, see Electron (disambiguation). ... An N-type semiconductor is obtained by carrying out a process of doping, that is adding a certain type of atoms to the semiconductor in order to increase the number of free (in this case negative) charge carriers. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen (~154 PPM). ...

CVD diamond growth has also been used in conjunction with lithographic techniques to incase microcircuits inside diamond. Researchers at Lawrence Livermore National Laboratory and the University of Alabama, Birmingham use this process to create designer diamond anvils^[16] as a novel probe for measuring electric and magnetic properties of materials at ultra high pressures using a Diamond Anvil Cell. Artistic rendition of a diamond anvil cell A diamond anvil cell (DAC) is a device used by physicists to exert extreme pressures on a material. ...

HPHT "type IIa" diamonds are, as of 2007, approaching the very high purity and crystallographic structure perfection required to replace silicon in applications like X-ray tomographic imaging at synchrotrons;^[17] they will be able to sustain the increased intensities of next generation light sources.^[18] Synchrotrons are now mostly used for producing monochromatic high intensity X-ray beams; here, the synchrotron is the circular track, off which the beamlines branch. ...

Synthetic gems

Adia Diamonds, Gemesis, New Age Diamonds and Tairus all produce gems made through HPHT technology. They are grown in split sphere high-pressure, high-temperature (HPHT) crystal growth chambers that resemble washing machines. The device bathes a tiny sliver of natural diamond in molten carbon at 1500 °C and 58,000 atm (5.9 GPa). This produces a rough diamond which can be cut down to a polished size close to half its original carat weight. Gemesis diamonds have an orange tint that is rare in natural diamonds. The yellow tint occurs when approximately five out of each 100,000 carbon atoms in the diamond crystal lattice are replaced with nitrogen atoms. Adia Diamonds produces diamonds in various shades of yellow and orange as well as blue and white (colorless). The blue color comes from doping the diamond with boron, rather than nitrogen, during the growth process. White diamonds must be grown in an environment free of nitrogen and boron, which makes them very difficult to produce. Yellow diamonds are more profitable because they can be made more quickly and cost less to manufacture than blue or colorless diamonds. Wikipedia does not have an article with this exact name. ... The Gemesis Corporation is a privately-held company founded by Carter Clarke in Sarasota, Florida, United States. ... New Age Diamonds is a Russian manufacturer of diamonds. ... Tairus (Russian: Ð¢Ð°Ð¹Ñ€ÑƒÑ, a portmanteau of Ð¢Ð°Ð¹ÑÐºÐ¾ (Thai) and Ð ÑƒÑÑÐºÐ¸Ð¹ (Russian)) is a synthetic gemstone manufacturer. ... For other uses, see Atom (disambiguation). ... In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... Wikipedia does not have an article with this exact name. ...

The mined diamond industry is evaluating marketing and distribution countermeasures to these less expensive alternatives. Gem-quality diamonds grown in a lab can be chemically, physically and optically identical to naturally occurring ones although they can be distinguished by spectroscopy in infrared, ultraviolet, or X-ray wavelengths. The DiamondView tester from De Beers uses UV fluorescence to detect trace impurities of nickel or other metals in HPHT diamonds, or hydrogen in some LP CVD diamonds. Furthermore, all three manufacturers have made public statements about selling their diamonds with full disclosure and have implemented measures to laser-inscribe serial numbers on their gemstones.^[8]^[19] Extremely high resolution spectrogram of the Sun showing thousands of elemental absorption lines (fraunhofer lines) Spectroscopy is the study of the interaction between radiation (electromagnetic radiation, or light, as well as particle radiation) and matter. ... Infrared spectroscopy (IR spectroscopy) is the subset of spectroscopy that deals with the infrared region of the electromagnetic spectrum. ... For other uses, see Ultraviolet (disambiguation). ... X-ray spectroscopy is a gathering name for several spectroscopic techniques for determining the electronic structure of materials by using x-ray excitation. ... De Beers, founded in South Africa by Cecil Rhodes, comprises companies involved in rough diamond exploration, diamond mining and diamond trading. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized Cadmium selenide (CdSe) quantum dots. ... General Name, symbol, number nickel, Ni, 28 Chemical series transition metals Group, period, block 10, 4, d Appearance lustrous, metallic and silvery with a gold tinge Standard atomic weight 58. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... For other uses, see Laser (disambiguation). ...

LifeGem is a company offering to synthesize diamonds from the carbonized remains of people or pets. LifeGem is a company offering to synthesize diamonds from the carbonized remains of people or pets. ...

Contents

History

The GE Diamond Project

Properties of synthetic diamond

Manufacturing technologies

High Pressure, High Temperature (HPHT)

Chemical Vapor Deposition of Diamond (CVD)

Applications

Wear Resistance

Electronics

Synthetic gems

See also

Notes

External links

Further reading

Contents

History GA_googleFillSlot("encyclopedia_square");

The GE Diamond Project

Properties of synthetic diamond

Manufacturing technologies

High Pressure, High Temperature (HPHT)

Chemical Vapor Deposition of Diamond (CVD)

Applications

Wear Resistance

Electronics

Synthetic gems

See also

Notes

External links

Further reading

History