The diamonds are highly appreciated and really valuable. For this reason, for more than 150 years man has tried to make diamonds artificially or synthetically. It was not a simple task, nor without controversy. we explain the history of artificial diamonds, who was their inventor, and what methods were used.

Who Invented the Artificial Diamond

The history of synthetic diamonds is shrouded in the greatest confusion. Scotsman James Ballantyne Hannay was the first to conceive the idea of ​​making artificial diamonds.

When Were Artificial Diamonds Invented

  • He tried to put it into practice and began his experiments in 1878 using animal charcoal oil, paraffin oil, and lithium as raw materials.
  • These elements were introduced into a steel cylinder and subjected to strong pressures to cause the evaporation of the fatty bodies which, when reacting with lithium, gave carbon, which remained adhered to the cylinder walls.
  • Hannay repeated the experiment eighty times in two years; only three cylinders withstood the pressure. In 1880, Hannay reported that he had found tiny crystals of pure carbon inside these.
  • Whose density of 3.5 corresponded to that of a diamond.
  • He sent these crystals to the head mineralogist at the British Museum, who declared that they were real diamonds.
  • Hannay’s diamonds were deposited in the British Museum, available to anyone who wanted to analyze them.

Technique Improvement

In 1896 Henri Moissan, inventor of the electric furnace also devoted his attention to obtaining artificial diamonds, using charcoal, iron, and graphite as raw materials, the latter as a lining for its container.

Origin Of Artificial Diamonds

He put the powdered mixture into his electric oven and subjected it to a temperature of 4,000 ° C.

The steel was completely melted and with it a significant part of the charcoal. He then immersed these molten materials in cold water.

  1. Since iron expands as it cools, Moissan hoped that sudden cooling would only harden the outer shell of the molten nodule. While inside there would be a magma that would tend to solidify, and therefore to expand.
  2. But, that in doing so it would meet the resistance of the envelope.
  3. Extremely high pressure would then be created in the nodule which, according to Moissan’s reasoning, would cause the formation of diamonds.
  4. Indeed, once the ingots were completely cold, he dissolved them in acid and found that inside them, mixed with graphite, crystals had formed whose density was between 3 and 3.5.
  5. These two experiments seem valid; that of Moissan, in particular, was confirmed by Sir William Crookes, who found that the Moissan method did indeed lead to the formation of diamonds.

It also reported that the industrialist Sir Andrew Noble had also managed to obtain diamonds by causing an explosion of cordite inside some steel cylinders, at 15,000 atmospheres of pressure and 4,000 ° C of temperature. In the years that followed, various researchers would see how well-founded the Moissan method was.

System Questioned

But in 1928, after twenty years of research, Sir Charles Parsons, inventor of the steam turbine, announced that he did not believe that Hannay or Moissan had managed to obtain real diamonds, but simply some type of crystal of great hardness, capable of scratching the glass.

According to Parsons, although a study based on the X-ray diffraction method (unknown in the time of Hannay and Moissan) showed that Hannay’s diamonds were true diamonds, it was not for this reason that Hannay made them.

Parsons cast doubt on Hannay and Moissan’s work without advancing the issue, which remained unclear until the late 1980s. (One question remains: if Hannay’s diamonds were not such diamonds, what carbon compound had he made then?).

Although Parsons ‘remarks were successful in discrediting Hannay, they did not affect Moissan’s credibility as dramatically, a scientific authority worth as much as Parsons’ own.

It is possible that Parsons’ skepticism stems from the notorious scam of Henri Lemoine, an adventurer who persuaded the president of De Beers. Sir Julius Wernher, that he had succeeded in making industrial diamonds.

Lemoine betrayed himself by sending Wernher specimens supposedly made by him that were actually natural diamonds from De Beers’ own mines.

The excessive resemblance of its alleged production to natural diamonds was precisely what the fraud discovered … and its author had to spend six years behind bars.

History of the industrial manufacture of artificial diamonds

In 1941, the American P. W. Bridgman, a pioneer of studies on high pressure, organized a research center for the study of the manufacture of artificial diamonds at high pressure, in which three North American societies participated.

World War II interrupted these studies, and they were independently resumed in 1949 by Norton International Inc. and General Electric.

Synthetic Diamond Manufacturing History

  • In 1955, General Electric claimed to have completed its investigations with success. But he was greatly disappointed when the Swedish firm Aktiebolaget announced that it had been working on the same issue. He had been doing it since 1930, and by February 1953 he had reached his goal.
  • The Swedish claim of paternity raised international skepticism. Especially taking into account that the team that claimed to have manufactured diamonds, led by engineer B. von Platen, stated that they were interested in jewelry diamonds and not industrial diamonds.
  • Now, to make diamonds of sufficient quality to be used in jewelry, it is necessary to apply pressures close to 60,000 atmospheres. A condition that could hardly be covered with the technology of the time. And yet the Swedes proved how well-founded their claims were.
  • The Swedish procedure, for which they had applied the most advanced resources that the mechanics and metallurgy of the moment could offer, consisted of introducing graphite pellets and a catalyst (such as nickel, cobalt, or iron) into a matrix made with tungsten carbide.
  • This matrix was subjected to very high pressures by means of a set of convergent truncated pyramids operated with a press. This system, known as the Belt System, was developed by General Electric.

In 1958, the South African firm De Beers, dedicated to the exploitation and commercialization of rough diamonds, announced that it had also obtained conclusive results.

Making artificial jewelry diamonds is not impossible, but it is uneconomical. At present, to make necklaces, earrings, rings, etc., natural diamonds are mainly used.

In 1970, General Electric succeeded in producing a one-carat artificial diamond with beautiful waters, now on display at the Smithsonian Institution in Washington, but its cost price is considerably higher than that of a natural stone.

The total production of the approximately 140 million carats currently made by South Africa, Sweden, Ireland, Russia, Japan, and the United States is made up of diamonds for industrial use. Such as grinders, electrophone read heads, drill heads, and so on…

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