This early research of diamond synthesis in the U.S., Sweden and the Soviet Union yielded the discovery of the CVD diamond (chemical vapor deposition) and HPHT diamond (high-pressure high-temperature) processes. These two processes still dominate the production of synthetic diamond, but researchers have since discovered a third and fourth method of diamond synthesis. A third method, known as detonation synthesis, entered the diamond market in the late 1990s. In this process, the detonation of carbon-containing explosives creates nanometer-sized diamond grains. Scientists have also demonstrated a fourth method of diamond synthesis, treating graphite with high-power ultrasound, but this process currently has no commercial application.
Introduction
Synthetic diamond
Synthetic diamond | Introduction
1954 1879 1954 1879
when was the first man made diamond made
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Bundy and Strong made the first improvements, then more were made by Hall. The GE team used tungsten carbide anvils within a hydraulic press to squeeze the carbonaceous sample held in a catlinite container, the finished grit being squeezed out of the container into a gasket. The team recorded diamond synthesis on one occasion, but the experiment could not be reproduced because of uncertain synthesis conditions, and the diamond was later shown to have been a natural diamond used as a seed. Hall achieved the first commercially successful synthesis of diamond on December 16, 1954, and this was announced on February 15, 1955.
Synthetic diamond | GE diamond project
Synthetic diamond (also referred to as laboratory-grown diamond, laboratory-created diamond, or cultured diamond) is a diamond made of the same material as natural diamonds: pure carbon, crystallized in an isotropic 3D form. Synthetic diamond are different from both natural diamond, which is created by geological processes, and imitation diamond, which is made of non-diamond material. Records of attempted diamond synthesis date back to the turn of the twentieth century. Numerous scientists claimed to have successfully synthesized diamonds between 1879 and 1928, but none was confirmed. In the 1940s, systematic research began in the United States, Sweden and the Soviet Union to grow diamonds, which culminated in the first reproducible synthesis of diamond in 1954.
Synthetic diamond | Introduction
Von Platen left the project before it succeeded in producing the first synthetic diamonds in 1953.
Baltzar von Platen (inventor) | Biography
He suggested that most diamonds that had been produced up to that point were likely synthetic spinel.
Synthetic diamond | History
Howard Tracy Hall (October 20, 1919 – July 25, 2008) was an American physical chemist and the first person who grew a synthetic diamond by a reproducible, verifiable, and witnessed process, using a press of his own design.
Tracy Hall | Introduction
His breakthrough was using a "belt" press, which was capable of producing pressures above and temperatures above . The press used a pyrophyllite container in which graphite was dissolved within molten nickel, cobalt or iron. Those metals acted as a "solvent-catalyst", which both dissolved carbon and accelerated its conversion into diamond. The largest diamond he produced was across; it was too small and visually imperfect for jewelry, but usable in industrial abrasives. Hall's co-workers were able to replicate his work, and the discovery was published in the major journal "Nature". He was the first person to grow a synthetic diamond with a reproducible, verifiable and well-documented process.
Synthetic diamond | GE diamond project
An independent diamond synthesis was achieved on February 16, 1953 in Stockholm by ASEA (Allmänna Svenska Elektriska Aktiebolaget), one of Sweden's major electrical manufacturing companies. Starting in 1949, ASEA employed a team of five scientists and engineers as part of a top-secret diamond-making project code-named QUINTUS. The team used a bulky split-sphere apparatus designed by Baltzar von Platen and Anders Kämpe. Pressure was maintained within the device at an estimated 8.4 GPa for an hour. A few small diamonds were produced, but not of gem quality or size. The work was not reported until the 1980s. During the 1980s, a new competitor emerged in Korea, a company named Iljin Diamond; it was followed by hundreds of Chinese enterprises.
Synthetic diamond | Later developments
The high-pressure synthesis of diamond in 1953 in Sweden and in 1954 in the US, made possible by the development of new apparatus and techniques, became a milestone in synthesis of artificial superhard materials. The synthesis clearly showed the potential of high-pressure applications for industrial purposes and stimulated growing interest in the field. Four years after the first synthesis of artificial diamond, cubic boron nitride c-BN was obtained and found to be the second hardest solid. Synthetic diamond can exist as a single, continuous crystal or as small polycrystals interconnected through the grain boundaries. The inherent spatial separation of these subunits causes the formation of grains, which are visible by the unaided eye due to the light absorption and scattering properties of the material.
Superhard material | Synthetic diamond
He left GE in 1955, and three years later developed a new apparatus for the synthesis of diamond—a tetrahedral press with four anvils—to avoid violating a U.S. Department of Commerce secrecy order on the GE patent applications.
Synthetic diamond | GE diamond project
After the 1797 discovery that diamond was pure carbon, many attempts were made to convert various cheap forms of carbon into diamond. The earliest successes were reported by James Ballantyne Hannay in 1879 and by Ferdinand Frédéric Henri Moissan in 1893. Their method involved heating charcoal at up to 3500 °C with iron inside a carbon crucible in a furnace. Whereas Hannay used a flame-heated tube, Moissan applied his newly developed electric arc 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.
Synthetic diamond | History
Iljin Diamond allegedly accomplished diamond synthesis in 1988 by misappropriating trade secrets from GE via a Korean former GE employee. Synthetic gem-quality diamond crystals were first produced in 1970 by GE, then reported in 1971. The first successes used a pyrophyllite tube seeded at each end with thin pieces of diamond. The graphite feed material was placed in the center and the metal solvent (nickel) between the graphite and the seeds. The container was heated and the pressure was raised to about 5.5 GPa. The crystals grow as they flow from the center to the ends of the tube, and extending the length of the process produces larger crystals.
Synthetic diamond | Later developments
James Ballantyne Hannay FRSE(1855–1931) was a Scottish chemist who believed he had synthesized diamond in 1880. However, modern testing showed that the surviving samples from his experiments were natural diamond, not synthetic. While his techniques were conducive to diamond formation, modern diamond production – not achieved until the 1950s – requires capabilities not available in Hannay's time. Hannay was also known for making precision instruments.
James Ballantyne Hannay | Introduction
It was known since experiments of Antoine Lavoisier that diamond was a form of carbon. Wells's story appeared a few years after the claims of James Ballantyne Hannay in 1879 and Ferdinand Frédéric Henri Moissan in 1893, that they had made artificial diamonds. Moissan heated charcoal (a form of carbon) and iron in a furnace until the iron melted; then rapidly cooled, the iron would generate high pressure and transform the charcoal into diamonds. Others tried to repeat this experiment in later years, and very small diamonds were created; commercially successful production of synthetic diamonds was not achieved until the 1950s.
The Diamond Maker | Historical background
In 1941, an agreement was made between the General Electric (GE), Norton and Carborundum companies to further develop diamond synthesis. They were able to heat carbon to about under a pressure of for a few seconds. Soon thereafter, the Second World War interrupted the project. It was resumed in 1951 at the Schenectady Laboratories of GE, and a high-pressure diamond group was formed with Francis P. Bundy and H. M. Strong. Tracy Hall and others joined the project later. The Schenectady group improved on the anvils designed by Percy Bridgman, who received a Nobel Prize for his work in 1946.
Synthetic diamond | GE diamond project
Initially, a week-long growth process produced gem-quality stones of around 5 mm (1 carat or 0.2 g), and the process conditions had to be as stable as possible. The graphite feed was soon replaced by diamond grit because that allowed much better control of the shape of the final crystal. The first gem-quality stones were always yellow to brown in color because of contamination with nitrogen. Inclusions were common, especially "plate-like" ones from the nickel. Removing all nitrogen from the process by adding aluminium or titanium produced colorless "white" stones, and removing the nitrogen and adding boron produced blue ones.
Synthetic diamond | Later developments
On 12 February 1898, the school was officially christened "McPherson College." In 1926, J Willard Hershey synthesized one of the world's earliest synthetic (man-made) diamonds on the McPherson College campus. Reporting on his experiments, Hershey wrote, "Since we first began our experiments in their manufacture more than 50 diamonds have been made synthetically at McPherson College, ranging in size from the smallest, one millimeter (about 1/25 inch) in diameter, to the largest, which, is two millimeters by one and one half millimeters by one millimeter, weighing 1/30 carat." One of the diamonds is on display at the McPherson Museum in McPherson, Kansas.
McPherson College | History
Moissan published his work in a series of articles in the 1890s. Many other scientists tried to replicate his experiments. Sir William Crookes claimed success in 1909. Otto Ruff claimed in 1917 to have produced diamonds up to 7 mm in diameter, but later retracted his statement. In 1926, Dr. J Willard Hershey of McPherson College replicated Moissan's and Ruff's experiments, producing a synthetic diamond; that specimen is on display at the McPherson Museum in Kansas. Despite the claims of Moissan, Ruff, and Hershey, other experimenters were unable to reproduce their synthesis. The most definitive replication attempts were performed by Sir Charles Algernon Parsons.
Synthetic diamond | History
A prominent scientist and engineer known for his invention of the steam turbine, he spent about 40 years (1882–1922) and a considerable part of his fortune trying to reproduce the experiments of Moissan and Hannay, but also adapted processes of his own. Parsons was known for his painstakingly accurate approach and methodical record keeping; all his resulting samples were preserved for further analysis by an independent party. He wrote a number of articles—some of the earliest on HPHT diamond—in which he claimed to have produced small diamonds. However, in 1928, he authorized Dr. C. H. Desch to publish an article in which he stated his belief that no synthetic diamonds (including those of Moissan and others) had been produced up to that date.
Synthetic diamond | History
The first lab-made diamonds can be dated back to the 1950s, while memorial diamonds started to appear in the market in the early 2000s. More than one company has claimed to be the first to provide memorial diamonds, and both Heart In Diamond and LifeGem have claimed to have a patent covering the growing of a "personalized gem diamond".
Memorial diamond | History
synthetic diamonds, invented in the 1950s, found almost immediate industrial applications; 3 billion carats (600 tonnes) of synthetic diamond is produced annually.
Carbon | Diamonds
Since the 1950s, techniques can produce diamonds of essentially any desired chemistry or size. Although some manufacturers do label their synthetic diamonds with serial numbers there is no guarantee that a given diamond is not man made, although sometimes an unnatural chemical composition or pattern of flaws may suggest a diamond is synthetic. It is much cheaper to produce diamonds through artificial synthesis than to mine them, although currently the cost of synthesis is still significant. The inability to guarantee that a diamond is naturally occurring could undermine the premium price still currently charged over synthetic diamonds. However, new technological advances have allowed some independent gem labs such as GIA (Gemological Institute of America) to issue a specific Synthetic Diamond Grading Report which identifies a diamond as laboratory-grown and laser inscribes it with "laboratory grown".
Diamonds as an investment | Synthetic diamonds
This early research of diamond synthesis in the U.S., Sweden and the Soviet Union yielded the discovery of the CVD diamond (chemical vapor deposition) and HPHT diamond (high-pressure high-temperature) processes. These two processes still dominate the production of synthetic diamond, but researchers have since discovered a third and fourth method of diamond synthesis. A third method, known as detonation synthesis, entered the diamond market in the late 1990s. In this process, the detonation of carbon-containing explosives creates nanometer-sized diamond grains. Scientists have also demonstrated a fourth method of diamond synthesis, treating graphite with high-power ultrasound, but this process currently has no commercial application.
Synthetic diamond | Introduction
A professor invents a way of manufacturing diamonds.
The Man Who Made Diamonds | Plot summary
Sir Robert Robertson (17 April 1869 – 28 April 1949) was a British chemist who served as HM Government's Government Chemist between 1921 and 1936. He was the first person to establish that two types of natural diamond existed.
Robert Robertson (chemist) | Introduction
Kelley experimented with several formulas and processes for making synthetic artificial gems. One method involved using temperature difference techniques to create crystals in a way water icicles are formed. One of these man-made gemstones made this way was a transparent clear crystal resembling glass. It looked to the naked eye like a real diamond when faceted correctly and no glass was involved in its manufacture. A second technique involves small pieces ("seeds") of mined gems put into a heated up chemical liquid. The liquid then is slowly cooled, and recrystallized to form larger pieces of the gemstone. Man-made gemstones grow from these "seeds." Kelley's technical success in growing crystals led to the founding of the Shelby Gem Factory in 1970.
Larry Paul Kelley | Shelby Gem Factory
These stone axes, made predominantly of the mineral corundum (sapphire and ruby in its colorful gem forms) were fashioned as early as 4000 BC, so that they represent the earliest use of the mineral corundum, as well. The finding's media coverage included a front-page article in China's largest English-language newspaper, the China Daily.
Peter Lu | Man's first use of diamond
These claims have been investigated by a number of scientists including Sir Robert Robertson, (1869–1949) the first person to establish that two types of natural diamond existed, who took a great personal interest in them. In 1876 he was elected a Fellow of the Royal Society of Edinburgh. His proposers were Thomas Edward Thorpe, William Dittmar, William Thomson, Lord Kelvin and Alexander Crum Brown. In the later years of his life Hannay turned away from scientific investigation and moved his attention to examining aspects of the origin and development of religion and published a number of works critical of the Hebrew Scriptures.
James Ballantyne Hannay | Life
Lu continued his interdisciplinary combination of art history and physics with his discovery, with a group of collaborators, of man's first use of diamond, in neolithic China. Prior to this work, evidence for man's first use of diamond was known primarily from Indian texts dating to the latter half of the first millennium BC, and there was no reported evidence for its use in prehistoric times. In 2005, Lu and collaborators reported strong evidence that the ancient Chinese used diamonds to polish ceremonial stone burial axes as early as 2500 BC, placing the earliest known use of diamond two thousand years before the mineral is known to have been used elsewhere.
Peter Lu | Man's first use of diamond
The first of the optically "improved" simulants was synthetic rutile (TiO, pure titanium oxide). Introduced in 1947–48, synthetic rutile possesses plenty of life when cut—perhaps too much life for a diamond simulant. Synthetic rutile's RI and dispersion (2.8 and 0.33) are so much higher than diamond that the resultant brilliants look almost opal-like in their display of prismatic colors. Synthetic rutile is also doubly refractive: although some stones are cut with the table perpendicular to the optic axis to hide this property, merely tilting the stone will reveal the doubled back facets. The continued success of synthetic rutile was also hampered by the material's inescapable yellow tint, which producers were never able to remedy.
Diamond simulant | 1947–1970
The Man Who Made Diamonds is a 1937 British crime film directed by Ralph Ince and starring Noel Madison, James Stephenson and Lesley Brook.
The Man Who Made Diamonds | Introduction
Hall left GE in 1955 and became a full professor of chemistry and Director of Research at Brigham Young University. At BYU, he invented the tetrahedral and Cubic press systems. He transferred the technology for the cubic press system to China in about 1960, and today the vast majority of the world's synthetic diamond powder is produced using the many thousands of cubic presses of Hall's design presently operating in that country. For many years, the first tetrahedral press was displayed in the Eyring Science center on campus at BYU. In the early 1960s, Hall invented the first form of polycrystalline diamond (PCD).
Tracy Hall | Later years
In 1772, the French scientist Antoine Lavoisier used a lens to concentrate the rays of the sun on a diamond in an atmosphere of oxygen, and showed that the only product of the combustion was carbon dioxide, proving that diamond is composed of carbon. Later in 1797, the English chemist Smithson Tennant repeated and expanded that experiment. By demonstrating that burning diamond and graphite releases the same amount of gas, he established the chemical equivalence of these substances.
Diamond | Etymology, earliest use and composition discovery
The first crystalline artificial diamond simulants were synthetic white sapphire (AlO, pure corundum) and spinel (MgO·AlO, pure magnesium aluminium oxide). Both have been synthesized in large quantities since the first decade of the 20th century via the Verneuil or flame-fusion process, although spinel was not in wide use until the 1920s. The Verneuil process involves an inverted oxyhydrogen blowpipe, with purified feed powder mixed with oxygen that is carefully fed through the blowpipe. The feed powder falls through the oxy-hydrogen flame, melts, and lands on a rotating and slowly descending pedestal below. The height of the pedestal is constantly adjusted to keep its top at the optimal position below the flame, and over a number of hours the molten powder cools and crystallizes to form a single pedunculated pear or "boule" crystal.
Diamond simulant | 1900–1947
He then sold these synthetic artificial man-made gems for just under a hundred dollars each. He progressed from making rubies to manufacturing other man-made gems including an imitation diamond. Kelley turned this into a business of making man-made artificial gems for all the traditional birthstones of each of the twelve months.
Larry Paul Kelley | Career
In the HPHT method, there are three main press designs used to supply the pressure and temperature necessary to produce synthetic diamond: the belt press, the cubic press and the split-sphere (BARS) press. Diamond seeds are placed at the bottom of the press. The internal part of press is heated above 1400 °C and melts the solvent metal. The molten metal dissolves the high purity carbon source, which is then transported to the small diamond seeds and precipitates, forming a large synthetic diamond. The original GE invention by Tracy Hall uses the belt press wherein the upper and lower anvils supply the pressure load to a cylindrical inner cell.
Synthetic diamond | High pressure, high temperature
For economic reasons, the growth of most synthetic diamonds is terminated when they reach a mass of to .
Synthetic diamond | Later developments
Synthetic diamonds are diamonds manufactured in a laboratory, as opposed to diamonds mined from the Earth. The gemological and industrial uses of diamond have created a large demand for rough stones. This demand has been satisfied in large part by synthetic diamonds, which have been manufactured by various processes for more than half a century. However, in recent years it has become possible to produce gem-quality synthetic diamonds of significant size. It is possible to make colorless synthetic gemstones that, on a molecular level, are identical to natural stones and so visually similar that only a gemologist with special equipment can tell the difference.
Diamond | Synthetics
However, synthetic rutile in a range of different colors, including blues and reds, were produced using various metal oxide dopants. These and the near-white stones were extremely popular if unreal stones. Synthetic rutile is also fairly soft (hardness ~6) and brittle, and therefore wears poorly. It is synthesized via a modification of the Verneuil process, which uses a third oxygen pipe to create a "tricone burner"; this is necessary to produce a single crystal, due to the much higher oxygen losses involved in the oxidation of titanium. The technique was invented by Charles H. Moore, Jr. at the South Amboy, New Jersey-based National Lead Company (later NL Industries).
Diamond simulant | 1947–1970
"The Diamond Maker" is a short story by H. G. Wells, first published in 1894 in the "Pall Mall Budget". It was included in "The Stolen Bacillus and Other Incidents", the first collection of short stories by Wells, published in 1895. In the story, a businessman hears an account from a man who has devoted years attempting to make artificial diamonds, only to end as a desperate outcast.
The Diamond Maker | Introduction
In 1837, Gaudin made the first synthetic rubies by fusing potash alum at a high temperature with a little chromium as a pigment. In 1847, Ebelmen made white sapphire by fusing alumina in boric acid. In 1877, Edmond Frémy and industrial glass-maker Charles Feil made crystal corundum from which small stones could be cut. In 1887, Fremy and Auguste Verneuil manufactured artificial ruby by fusing BaF and AlO with a little chromium at red heat. In 1903, Verneuil announced he could produce synthetic rubies on a commercial scale using this flame fusion process, later also known as the Verneuil process.
Ruby | Synthetic and imitation rubies
There are several methods used to produce synthetic diamonds. The original method uses high pressure and high temperature (HPHT) and is still widely used because of its relatively low cost. The process involves large presses that can weigh hundreds of tons to produce a pressure of 5 GPa at 1500 °C. The second method, using chemical vapor deposition (CVD), creates a carbon plasma over a substrate onto which the carbon atoms deposit to form diamond. Other methods include explosive formation (forming detonation nanodiamonds) and sonication of graphite solutions.
Synthetic diamond | Manufacturing technologies
The practice is documented among European aristocracy as early as the 15th century, though ruby and sapphire were more desirable gemstones. The modern popularity of diamonds was largely created by De Beers Consolidated Mines, which established the first large-scale diamonds mines in South Africa. Through an advertising campaign beginning in the 1930s and continuing into the mid-20th century, De Beers made diamonds into a key part of the betrothal process and a coveted symbol of status. The diamond's high value has been the driving force behind dictators and revolutionary entities, especially in Africa, using slave and child labor to mine blood diamonds to fund conflicts.
Diamond (gemstone) | Introduction
This was the first simulated diamond variety. It became the first business anywhere to mass-produce cubic zirconia (CZ). In the 1970s the Shelby Gem Factory rode a wave of popularity CZ then enjoyed. At its peak, tons of cubic zirconia were produced for the world market. Subsidiary factories were opened in China, India, and Panama to keep up with demand. The factory closed in 2019, after 50 years of manufacturing.
Shelby Gem Factory | History
As with many important inventions, the circumstances surrounding Hall's synthesis is the object of some controversy. What is undoubted is that he produced synthetic diamond in a press of his own design on December 16, 1954 and that he and others could do it over and over in the following week and that success led to the creation of a major super materials industry. What is also undoubted is that Hall was one of a group of about a half dozen of researchers who had focused on the syntheses for almost four years. These years had seen a succession of failed experiments, an increasingly impatient management, and a complex blend of sharing and rivalries among the researchers.
Tracy Hall | The invention
In 1919, Lazare Kaplan's cousin, mathematician Marcel Tolkowsky, first published the mathematical formula for diamonds cut to "ideal" proportions, a formula designed to optimise the brilliance, fire and sparkle in a polished diamond. In the same year, LKI became the first commercial-scale operation to cut its diamonds to ideal proportions. In 1957, LKI developed the modern oval cut, and in 1983 it developed and patented the laser inscription process. In 2002, LKI was awarded a patent, jointly with the General Electric Company, for the high-pressure high-temperature (HPHT) process for improving the color of certain all-natural diamond types. In addition, LKI has secured numerous patents on diamond setting techniques and innovations in displays for loose polished stones and jewelry.
Lazare Kaplan International | Technical innovation
Auguste Victor Louis Verneuil (; 3 November 1856 – 27 April 1913) was a French chemist best known for inventing the first commercially viable process for the manufacture of synthetic gemstones. In 1902 he discovered the "flame fusion" process, today called the Verneuil process, which remains in use today as an inexpensive means of making artificial corundum, or rubies and sapphires.
Auguste Victor Louis Verneuil | Introduction
After contemplating the diamond for almost a year, Winston chose Lazare Kaplan to study the Jonker diamond. Lazare Kaplan was chosen to cut the diamond into several gemstones. The process of examining the diamond to determine the optimal cuts took place over the course of several months. On 27 April 1936, the first cut was made which cut off a 35-carat section, finally ending with the diamond being cut into 13 pieces. The largest piece produced the Jonker I, a 142.90 ct D-color flawless diamond which was later re-cut to 125.35 carats.
The Jonker | Cut
In 1902 Joseph Asscher designed and patented his namesake original Asscher cut. This emblematic cut was the world's first patented diamond cut protecting it from replication by other companies. The Asscher Diamond Company held its exclusive patent until the Second World War and saw strong sales internationally, particularly during the 1920s and 30s when the cut and company were both at the height of success. The original design had 58 Step cut facets, a small table, high crown and steep pavilion with cut corners. An accurate description would be a cut cornered square emerald cut diamond. Also known as square emerald cuts, Asscher cut diamonds are roughly square in shape when viewed from above but have cut corners for more light to enter the diamond.
Royal Asscher Diamond Company | The Asscher Cut
HMS "Diamond" was a destroyer of the British Royal Navy. She was built by John Brown & Company in Clydebank, Scotland, and launched on 14 June 1950. This ship was John Brown & Company's first all-welded ship (as opposed to the rivetted construction more commonly used up to that time).
HMS Diamond (D35) | Introduction
Synthetic diamonds are produced via high pressure, high temperature (HPHT) or chemical vapor deposition (CVD) technology. These diamonds have numerous industrial and commercial uses including cutting tools, thermal conductors and consumer diamond gemstones.
List of synthetic diamond manufacturers | Introduction
Asscher’s grandfather founded the Asscher Diamond Company (now the Royal Asscher Diamond Company) in 1854, but it was Abraham and his brother Joseph who built its international fame. In 1907 the brothers opened a new factory at 127 Tolstraat in Amsterdam and soon they received a request from King Edward VII of Great Britain to cleave the legendary Cullinan Diamond, the largest rough gem-quality diamond ever found.
Abraham Asscher | Early career
Removing nitrogen also slowed the growth process and reduced the crystalline quality, so the process was normally run with nitrogen present. Although the GE stones and natural diamonds were chemically identical, their physical properties were not the same. The colorless stones produced strong fluorescence and phosphorescence under short-wavelength ultraviolet light, but were inert under long-wave UV. Among natural diamonds, only the rarer blue gems exhibit these properties. Unlike natural diamonds, all the GE stones showed strong yellow fluorescence under X-rays. The De Beers Diamond Research Laboratory has grown stones of up to for research purposes. Stable HPHT conditions were kept for six weeks to grow high-quality diamonds of this size.
Synthetic diamond | Later developments
In 1796 Smithson Tennant was experimenting on diamonds when he decided to burn one. Using only sunlight and a magnifying glass he managed to ignite a diamond sufficiently for it to produce a gas, which he collected and was able to identify as carbon dioxide. Having started with only diamond and oxygen, and produced a gas which contains only carbon and oxygen, Tennant had discovered that diamonds are made of carbon. Unaware of atomic theory at the time, scientists were unable to explain how carbon, already known to exist as one of the softest substances in the form of graphite, could also be the sole constituent element of the hardest known substance: diamond.
Chemistry: A Volatile History | Smithson Tennant discovers what diamonds are made of
The modern era of diamond mining began in the 1860s in Kimberley, South Africa with the opening of the first large-scale diamond mine. The first diamond there was found in 1866 on the banks of the Orange River and became known as the Eureka Diamond. In 1869, an even larger diamond was found on the slopes of Colesberg Kopje on the farm Vooruitzigt belonging to the De Beers brothers. This sparked off the famous "New Rush" and within a month, 800 claims were cut into the hillock which were worked frenetically by two to three thousand men. As the land was lowered so the hillock became a mine—in time, the world-renowned Kimberley Mine.
Diamond (gemstone) | Modern
The first purely synthetic element to be made was curium, synthesized in 1944 by Glenn T. Seaborg, Ralph A. James, and Albert Ghiorso by bombarding plutonium with alpha particles.
Synthetic element | Curium
Diamonds became popular as ornaments in jewelry in the 1400s and the different techniques and styles of diamond cuts were gradually developed over many years. Lodewyk van Bercken was a Flemish diamond polisher who invented the scaif. This ingenious polishing wheel enabled him to quickly cut facets into diamonds with precision. The scaif transformed the diamond trade. It opened the doors to the creation of complex diamond cuts which otherwise would have never been possible. The scaif is still used today as an essential tool for the diamond industry in order to create facets on diamonds. In 1475, Lodewyk van Bercken invented the world's first Pear Cut Diamond.
Lodewyk van Bercken | Legacy
He decided to enter into diamond mining, having previously had experience prospecting in California. This was soon after the first discovery of diamonds in the region. Babe was unimpressed with the technique that was then in use on the diamond fields, of excavating a quantity of gravel and then removing it to the nearest water source, often some distance away, for washing and screening. He devised a type of dry sorting pan that could sort diamonds from the gravel without the use of water. This machine was first used at the Vaal River field in 1871 and became known as the "Yankee Baby" or simply the "Baby" after Babe's surname.
Jerome Babe | Biography
The company developed five generations of plasma reactor designs using software simulations of plasma physics to develop its technology for managing a high-density plasma for diamond growth at extremely high temperatures. As contrasted with diamond simulants (which are non-diamond material that appears similar to diamond) and natural mined diamonds, synthetic diamonds are actual diamonds that are produced by a manufacturing process. The company "grows" diamond using the chemical vapor deposition (CVD) method, by placing a small piece of natural diamond in a plasma reactor for a period of about two weeks. The resulting man-made diamond is essentially identical to natural diamond (atomically, molecularly, chemically, visually, in terms of hardness, optical brilliance, crystalline structure, etc.) but without the resource intensiveness, hazards, and environmental concerns that occur with diamond mining.
Diamond Foundry | Technology
National Lead and Union Carbide were the primary producers of synthetic rutile, and peak annual production reached 750,000 carats (150 kg). Some of the many commercial names applied to synthetic rutile include: "Astryl", "Diamothyst", "Gava" or "Java Gem", "Meredith", "Miridis", "Rainbow Diamond", "Rainbow Magic Diamond", "Rutania", "Titangem", "Titania", and "Ultamite". National Lead was also where research into the synthesis of another titanium compound—strontium titanate (SrTiO, pure tausonite)—was conducted. Research was done during the late 1940s and early 1950s by Leon Merker and Langtry E. Lynd, who also used a tricone modification of the Verneuil process. Upon its commercial introduction in 1955, strontium titanate quickly replaced synthetic rutile as the most popular diamond simulant.
Diamond simulant | 1947–1970
The process of Diamond cutting has been known in the Indian Subcontinent as early as 6th century AD. A 6th century treatise Ratnapariksa, or Appreciation of Gems states that the best form in which to have the diamond is in its perfect natural octahedral crystal form, and not as a cut stone indicating that diamond cutting was widespread practice. Al Beruni also describes the process of diamond grinding using lead plate in the 11th century AD Agastimata written before 10th century states: A 12th or early 13th century diamond ring attributed to Muhammad Ghauri contains two diamonds whose crude Octahedral natural states are maintained but they are in limpid condition exhibiting diamond polishing and shaping predated Europe where first diamond processing dates back to mid 14th century AD.
Diamond cut | Ancient India
The first Rapaport Price List was produced by Martin Rapaport, the Rapaport Diamonds Group founder, in 1978.
Rapaport Diamond Report | History
ALTR Created Diamonds is a division of the R.A. Riam Group, a wholesale jeweler based in New York City. The principles of Riam Group were heirs to a heritage of 80 years in the mined diamond business, when they released their first lab-grown diamond. Riam introduced ALTR Created Diamonds at JCK Las Vegas trade show in 2016.
ALTR Created Diamonds | History
The development of laser heating began only 8 years after Charles Weir, of the National Bureau of Standards (NBS), made the first diamond anvil cell and Alvin Van Valkenburg, NBS, realized the potential of being able to see the sample while under pressure. William Bassett and his colleague Taro Takahashi focused a laser beam on the sample while under pressure. The first laser heating system used a single 7 joule pulsed ruby laser that heated the sample to 3000 °C while at 260 kilobars. This was sufficient to convert graphite to diamond. The major flaws within the first system related to control and temperature measurement.
Diamond anvil cell | History
Historically diamonds were known to be found only in alluvial deposits in southern India. India led the world in diamond production from the time of their discovery in approximately the 9th century BC to the mid-18th century AD, but the commercial potential of these sources had been exhausted by the late 18th century and at that time India was eclipsed by Brazil where the first non-Indian diamonds were found in 1725.
Carbon | Diamond
The cubic press was created shortly thereafter to increase the volume to which pressure could be applied. A cubic press is typically smaller than a belt press and can more rapidly achieve the pressure and temperature necessary to create synthetic diamond. However, cubic presses cannot be easily scaled up to larger volumes: the pressurized volume can be increased by using larger anvils, but this also increases the amount of force needed on the anvils to achieve the same pressure. An alternative is to decrease the surface area to volume ratio of the pressurized volume, by using more anvils to converge upon a higher-order platonic solid, such as a dodecahedron.
Synthetic diamond | High pressure, high temperature
After a failed experiment that involved compressing a sample with a diamond piston inserted into a cylindrical hole bored into a 7.5 carat diamond crystal, Weir proposed an opposed anvil device that would take advantage of the high compressive strength of diamond (as opposed to its less impressive tensile strength) to perform infrared absorption measurements at high pressure. In 1958, Weir took the lead role in designing the first diamond anvil cell, and fabricated it himself using the tools available to him in the laboratory.
Charles E. Weir | Career
The inner diamond has a flat shape, its size is 1.9 × 2.1 × 0.6 mm. The diamond was discovered during the sorting process by the specialists of the Yakut Diamond Trading Company (YDTC). Specialists handed it over to the Research and Development Geological Enterprise of Alrosa. At the Enterprise, diamond was studied by a complex of methods, including Raman spectroscopy and infrared spectroscopy, as well as X-ray microtomography. As a result of the research, it was concluded that the inner diamond appeared before the external diamond. How an external diamond formed is not entirely clear. Two hypotheses are proposed to explain the formation of an external diamond.
Matryoshka (diamond) | Introduction
The company web site shows an example of the lettering of one of its laser inscriptions, which includes both the words "Gemesis created" and the serial number prefix "LG" (laboratory grown).
Synthetic diamond | Gemstones
As De Beers Industrial Diamond, the company was set up initially to concentrate on the industrial applications of natural diamond. Following the development of diamond synthesis in the early 1950s, the company acquired the technology and by 1958 was able to manufacture material based on a high pressure, high temperature process. By the 1960s, the company was offering a range of diamond grit products that was followed by nickel and coated diamond materials plus grinding products based on cubic boron nitride. In 1992, breakthroughs in chemical vapour deposition technology opened the opportunity to synthesize diamond films and a new raft of application areas became possible.
Element Six | History
The history of Alrosa dates back to 1954, when the first primary deposit of diamonds in the Soviet Union, the kimberlite pipe Zarnitsa, was found. In 1955 the Mir kimberlite pipe and the Udachnaya pipe were discovered. A total of fifteen primary diamond sources were found in 1955. In 1957, a decision was made to begin mining and production operations on alluvial and ore deposits in Yakutia. To manage the facilities construction and subsequent operations, the Yakutalmaz group of companies was established with headquarters in Mirny. The first commercial-grade diamonds were recovered the same year. Two years later, the Soviet Union sold the first shipment of diamonds on the world market.
Alrosa | History
The designer and inventor of the first South Africa origin patent cut diamonds registered in over 30 countries worldwide The My Girl diamond USA patent number US 29/175,153 dated January 30, 2003, is the flagship diamond for Shimansky currently sold exclusively at shimansky stores only. the only diamond in the world with the perfect balance of fire, brilliance and scintillation 33.33% in each area, making the diamond sparkle from every angle under any light condition shaping the internal light while absorbing external light to its maximum.
Yair Shimansky | My Girl Diamond
The Nassak Diamond was imported into the United States in 1927, and was considered one of the first 24 great diamonds of the world by 1930. American jeweller Harry Winston acquired the Nassak Diamond in 1940 in Paris, France and recut it to its present flawless emerald cut shape. Winston sold the diamond to a New York jewellery firm in 1942. Mrs. William B. Leeds of New York received the gem in 1944 as a sixth anniversary present and wore it in a ring. The Nassak Diamond was last sold at an auction in New York in 1970 to Edward J.
Nassak Diamond | Introduction
The barrel is filled with oil, which pressurizes upon heating, and the oil pressure is transferred to the central cell. The synthesis capsule is heated up by a coaxial graphite heater and the temperature is measured with a thermocouple.
Synthetic diamond | High pressure, high temperature
The diamond was discovered by South African farmer Johannes Jacobus Jonker on the 17th of January 1934. The diamond was first purchased by Joseph Bastiaenen an agent of the Diamond Corporation Ltd, a company owned by Sir Ernest Oppenheimer. In 1935 it was purchased by Harry Winston, a New York diamond dealer, for 150,000 pounds. Harry Winston toured the United States with the diamond that was photographed with a number of stars such as Claudette Colbert and Shirley Temple.
The Jonker | Discovery
Several companies also offer memorial diamonds grown using cremated remains. Gem-quality diamonds grown in a lab can be chemically, physically and optically identical to naturally occurring ones. The mined diamond industry has undertaken legal, marketing and distribution countermeasures to protect its market from the emerging presence of synthetic diamonds. Synthetic diamonds can be distinguished by spectroscopy in the infrared, ultraviolet, or X-ray wavelengths. The DiamondView tester from De Beers uses UV fluorescence to detect trace impurities of nitrogen, nickel or other metals in HPHT or CVD diamonds. At least one maker of laboratory-grown diamonds has made public statements about being "committed to disclosure" of the nature of its diamonds, and laser-inscribed serial numbers on all of its gemstones.
Synthetic diamond | Gemstones
In 1908, Oats was appointed chairman of De Beers. That year he told the company's annual general meeting, "Really, if one could believe all the stories which have been circulating about the discovery of new mines and methods for the artificial making of diamonds, it would be a marvel that people are willing to buy diamonds at all. ... There have been numerous discoveries of alleged mines in all parts of the world, but none of them have come to the serious production stage except German S.W. Africa where a discovery has been made of some superficial deposits of diamonds, but fortunately for our prices, these, singularly enough, are all small in size." Oats was making a serious error in discounting the German discovery, which had large and high quality diamonds, and dismissing Ernest Oppenheimer's Premier Mine, which was producing more than the total output of De Beers.
Francis Oats | Chairman of De Beers
In 1974, Boart International invested capital which helped Longyear to become the world's leading manufacturer of diamond bits. Boart Longyear engineers in North Bay, Ontario, secured a reliable source of high-performance synthetic diamonds, which triggered the development of a new bit design – the impregnated-diamond bit. With decades of powder metallurgy experience behind them, Longyear engineers set out to develop a new crown that consisted of synthetic diamonds evenly distributed throughout a composite matrix. This new design could drill further and faster than surface-set bits and cut through much harder material. By 1980, 75 percent of Longyear's Canadian-produced bits were of the new impregnated type, and Longyear was manufacturing diamond bits in more than eight countries.
Boart Longyear | 1974 to 2000
J Willard Hershey (6 February 1876, Gettysburg, Pennsylvania – 27 September 1943) was an American chemist who was best known for his work on synthetic diamond production. There is, however, some doubt whether his success was real, or whether co-workers introduced the diamonds without his knowledge. He also studied the effects of rare gases such as helium on animal life. He was awarded a B.S. degree in 1907 and an M.S. degree in 1910 by Gettysburg College. He studied at Harvard in 1907 and 1908 and at Johns Hopkins University in 1910 and 1911, and was awarded a Ph.D. by the University of Chicago in 1924.
J. Willard Hershey | Introduction
The novel first appeared in "Fantastic Adventures" in 1950 before a revision was printed in book form. It has since had numerous reprints, notably a 1953 Italian translation and a 1957 Pyramid Books reprint under the title "The Synthetic Man".
The Dreaming Jewels | Publication history
I thought I had the jack of diamonds at first. I guess he laid down top pair, but I've laid down top pair before when there was four to a flush on board."
David Steicke | Introduction
In popular culture, diamond threads were first described by Arthur C. Clarke in his sci-fi novel "The Fountains of Paradise" set in the 22nd century, written in 1979. Nanothreads were first investigated theoretically in 2001 by researchers at Penn State University and later by researchers at Cornell University. In 2014, researchers at Penn State University created the first sp-carbon nanothreads in collaboration with Oak Ridge National Laboratory and the Carnegie Institution for Science. Prior to 2014, and despite a century of investigation, benzene was thought to produce only hydrogenated amorphous carbon when compressed. As of 2015, threads at least 90 nanometers in length had been created (compared to .5 meters for CNTs).
Carbon nanothread | History
The hardness of synthetic diamond (70–150 GPa) is very dependent on the relative purity of the crystal itself. The more perfect the crystal structure, the harder the diamond becomes. It has been reported that HPHT single crystals and nanocrystalline diamond aggregates (aggregated diamond nanorods) can be harder than natural diamond.
Superhard material | Synthetic diamond
It was done secretly, so that others would not copy his work, and so that he could sell his diamonds without it being known that they could be produced in large quantities. After his money ran out he conducted his experiments in cheap lodgings in Kentish Town, and had various menial jobs. He finally succeeded when, using an idea suggested by experiments of Gabriel Auguste Daubrée, he put the mixture which might produce diamonds together with dynamite in a cylinder too strong to burst. However, as he inspected the results a neighbour in the lodgings house, thinking he was a bomb-making anarchist, told him he had called the police.
The Diamond Maker | Story
The diamond was dedicated on February 19, 2006.
Pat Kenelly | Introduction
In 1967, 100 years after the diamond's discovery, De Beers purchased the diamond and donated it to the South African people. The diamond was placed in the Kimberley Mine Museum, where it is currently on display.
Eureka Diamond | First purchase to current time
As there is little evidence for diamond cutting before 1400, it is likely the jeweller had merely squared off (described as ""quarré"" on the original invoice) its natural form. When the Brothers made their first appearance in an inventory—that of Duke Philip the Good of Burgundy in 1419—the jewel was described as: In 1587 the Three Brothers were listed among jewels delivered to Elizabethan courtier Mary Radcliffe and described as:
Three Brothers (jewel) | Description
The Rise and Fall of Diamonds by Edward Jay Epstein. (1982) Industrial Diamond review volume 40.(1980) The Diamond Invention by Edward Jay Epstein. (1982)
Otto Oppenheimer | Bibliography
The process of diamonds being used for drilling ornamental beads dates back to 2nd millennium BC. Archaeologists working in Yemen have excavated beads with evidences of diamond drilling from 1200 BC to 1st century AD from the site of Hajar ar Rayhani, while double diamond drilling from 7th century BC. The double diamond drill technique was present in Western India prior to 600 BC (7th century BC). There is also evidence of technique of double diamond drilling from Southern Thailand dating back to 400 BC. Before diamonds were discovered in Brazil in the 1700s, India was the only place where diamonds were mined.
Diamond (gemstone) | Early
In 1988, he was commissioned by them to act as master cutter for the Centenary Diamond, a task which took three years. This monumental diamond remained untouched for over a year while the correct tools and technical conditions were created by Gabi and his team. The gem was "kerfed" (hand cleaved) in order to avoid heat- or vibration-related damage from saws or lasers. Finally in 1991 the Tolkowsky's De Beers Centenary Diamond was finished weighing presents 247 facets and is acknowledged as the largest, most colour-perfect and flawless modern diamond cut in the world.
Gabi Tolkowsky | Centenary Diamond
Diamond is an allotrope of carbon where the atoms are arranged in a modified version of face-centered cubic ("fcc") structure known as "diamond cubic". It is known for its hardness (see table above) and incompressibility and is targeted for some potential optical and electrical applications. The properties of individual natural diamonds or carbonado vary too widely for industrial purposes, and therefore synthetic diamond became a major research focus.
Superhard material | Diamond
Henri Lemoine ("fl." 1905–1908) was a French fraudster who claimed to be able to produce synthetic diamonds.
Henri Lemoine (fraudster) | Introduction
Diamond was a merchant ship built on Isle of Man in 1824. She made a number of voyages between England and India with cargo and undertook one voyage transporting convicts to New South Wales.
Diamond (1835 ship) | Introduction
The Diamond (released in the US as The Diamond Wizard) is a 1954 British film noir crime film starring Dennis O'Keefe, Margaret Sheridan and Philip Friend. It has the distinction of being Britain's first 3D film, though according to the British Film Institute (BFI), it was shown in 3D only once, on 13 September 2006 in Hollywood. Despite the 2006 showing the film was listed on the BFI 75 Most Wanted list of lost films. The film, however, is not lost and can be viewed on Amazon Prime.
The Diamond (film) | Introduction
Cubic boron nitride or c-BN was first synthesized in 1957 by Robert H. Wentorf at General Electric, shortly after the synthesis of diamond. The general process for c-BN synthesis is the dissolution of hexagonal boron nitride (h-BN) in a solvent-catalyst, usually alkali or alkaline earth metals or their nitrides, followed by spontaneous nucleation of c-BN under high pressure, high temperature (HPHT) conditions. The yield of c-BN is lower and substantially slower compared to diamond's synthetic route due to the complicated intermediate steps. Its insolubility in iron and other metal alloys makes it more useful for some industrial applications than diamond.
Superhard material | History
At the World's Columbian Exposition in 1893 Labram ran a machinery exhibition. In 1893 Labram was employed by the De Beers company in Kimberley to build and manage a crushing mill. In 1898 he was promoted to chief engineer. Under Labram's supervision as manager of the crushing plant, Fred Kirsten devised an automated diamond extraction process. Up to that time all diamonds were manually extracted by sight.
George Labram | Career
Heritage: The Case of the Hannay Diamonds. New Scientist, 21 February 1980, p. 591.
James Ballantyne Hannay | External links
The history of diamond cuts in Europe can be traced to the late Middle Ages, before which time diamonds were employed in their natural octahedral state—anhedral (poorly formed) diamonds simply were not used in jewelry. The first "improvements" on nature's design involved a simple polishing of the octahedral crystal faces to create even and unblemished facets, or to fashion the desired octahedral shape out of an otherwise unappealing piece of rough. This was called the "point cut" and dates from the mid 14th century; by 1375 there was a guild of diamond polishers at Nürnberg. By the mid 15th century, the point cut began to be improved upon: the top of the octahedron would be polished or ground off, creating the "table cut".
Diamond cut | Europe
During the 1930s, Longyear took on a project drilling for core samples for the proposed Golden Gate Bridge in San Francisco. In spite of the financial crisis, the 1930s saw improvements in diamond drilling technology, including the use of industrial-quality diamonds mined in Africa that were called “boarts.” In 1936, South Africa's Anglo American Corporation formed Boart Products South Africa (Pty) Limited, which was later named Boart International. The new company developed the first mechanically-set diamond core bits, which were less expensive than the hand-set core bits that used more expensive Brazilian diamonds (carbonados).
Boart Longyear | 1920s to 1930s
The Hope Diamond was formed deep within the Earth approximately 1.1 billion years ago. Like all diamonds, it is formed when carbon atoms form strong bonds. The Hope Diamond was originally embedded in kimberlite, and was later extracted and refined to form the gem it is today. The Hope Diamond contains trace amounts of boron atoms intermixed with the carbon structure, which results in the rare blue color of the diamond.
Hope Diamond | Geological beginnings
Diamonds is a British television drama produced by ATV for the ITV in 1981. Created by John Brason, the series was set amongst the exclusive world of diamond merchants, Coleman and Sons, in London and lasted for thirteen episodes.
Diamonds (British TV series) | Introduction