The History of Lab Grown Diamonds

Synthetic, lab-grown, artisan-created, man-made, or cultured. Whatever you choose to call them, lab-grown diamonds are highly controversial these days, and the diamond media reports regularly on new developments in this growing industry. Whether you like it or not, lab-grown diamonds are not going away, and the technology used to grow them is improving rapidly. As with any product or service, when there is demand for something, companies will continue to enter the marketplace to provide the supply to meet that demand. The demand for lab-grown diamonds is growing in some of the major diamond-consuming nations, but not in others. In my next series of articles, I will take an in-depth look at the burgeoning phenomenon of lab-grown diamonds. I’ll examine their history, how they are made, and their applications. I’ll also discuss how the natural diamond market is reacting to them, how the supply/demand fundamentals are shaping up, and how they are currently being priced in the market.

While we tend to think about lab-grown diamonds primarily in the context of the gem and jewelry industry, the truth is that scientists and product engineers are looking for new ways to make diamonds that can be used in other industrial and medical applications. Imagine car paint infused with diamonds so it can’t be scratched, or nanoclusters of diamonds that can deliver chemotherapy drugs directly to the cells without the negative effects of today’s delivery agents. Although we commonly hear about two primary methods for growing diamonds, namely High-Pressure, High Temperature (HPHT) and Chemical Vapor Deposition (CVD), scientists have successfully found other ways to manufacture diamonds in a laboratory.

Ever since the 1797 discovery that diamond is a pure form of carbon, scientists have been working on and theorizing ways to manufacture them from more abundant forms of carbon. In 1911, science fiction writer H. G. Wells described the concept of synthetic diamonds in a short story titled “The Diamond Maker”. James Ballantyne and Ferdinand Frédéric Henri Moissan reported the earliest written accounts of attempts to manufacture diamonds, in 1879 and 1893, respectively. Hanney reported that he heated charcoal to temperatures above 3500°F, along with iron, inside a crucible furnace. The rapid cooling of iron created the high pressure needed in addition to the heat already supplied.

Moissan, on the other hand, was first turned onto the idea after the discovery of small diamonds in a meteorite crater in Arizona. He used his newly-invented electric arc furnace, in which an electric arc was struck between carbon rods inside a block of lime. While Moissan believed that he had discovered a new way to grow diamonds, he had actually created a new material that was made of silicon carbide, and not a diamond. Moissanite, the gemstone that Moissan unknowingly created, still bears his name today. He was awarded the Nobel Prize in Chemistry in 1906.

In 1917, Otto Ruff adapted and repeated Moissan’s experiments, and reported that he had produced diamonds larger than 7 mm, but he later retracted his statements. In 1926, Dr. J. Willard Hershey of McPherson Collage in Kansas recreated Moissan and Ruff’s work, and successfully created a synthetic diamond, which can still be found on display at the McPherson museum in Kansas. Prominent engineer Sir Charles Algernon Parsons, who amassed a great fortune and standing after his invention of the steam turbine in 1884, reportedly spent as long as 40 years, and a sizable part of his fortune, trying to make diamonds. Although he is believed to have been successful, in 1928, for unknown reasons, he published an article in which he stated his belief that no synthetic diamonds had been produced to that date, and that other ‘successful’ attempts had likely produced synthetic spinel, not diamond.

In 1941, General Electric assembled a team to advance diamond synthesis techniques. Their work was interrupted by the Second World War, but was later resumed. In December 1954, Tracy Hall of GE announced a verified and repeatable process to synthesize diamonds. His breakthrough utilized a ‘belt’ press that could produce pressure in excess of 10 GPa, and temperatures above 3630°F. The press used a container in which graphite dissolved in catalyst metals such as nickel, cobalt, or iron, which both dissolved the carbon, and accelerated conversion into diamond. The largest diamond he produced was 0.15 mm across, far too small for use in jewelry, but perfect for industrial applications. His method could mass-produce synthetic diamond for the first time, and GE was a dominant player in industrial diamond development for many years after. Hall received the American Chemical Society Award for Creative Innovation for his work.

The Swedish electrical utility ASEA (Allmänna Svenska Elektriska Aktiebolaget) reportedly synthesized diamonds before GE in 1953, but kept their discovery a secret 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. Iljin Diamond allegedly accomplished diamond synthesis in 1988 by misappropriating trade secrets from GE, via a Korean former GE employee.

By 1971, GE had managed to grow gem-quality diamonds for the first time, using seeds of natural diamond in a process now known as HPHT, still the primary manufacturing technique today. Leaving the machines in use for up to a week could produce stones as large as 5mm (1 carat). The first gem-quality stones were always yellow to brown in color because of contamination with nitrogen, and inclusions were common, especially the introduction of nickel into the crystal structure. Removing all nitrogen from the process by adding aluminum or titanium produced colorless "white" stones, and removing the nitrogen and adding boron produced blue ones. Removing nitrogen also slowed the growth process and reduced the crystalline quality, so the process was normally run with nitrogen present. After decades of dominance, GE sold its super abrasives unit in 2003 to a private equity firm. It was sold again to Sweden’s Sandvik in 2007.

Also in the 1970s, Soviet scientists took advantage of the invention of the microwave. They rediscovered a new diamond-like mineral created by two German mineralogists in 1937, whose work was cut-short with the onset of World War II. The Germans found that the mineral occurred so infrequently in nature that they failed to even give it a name. In an attempt to grow diamond crystals, the Soviets took the mineral, now named zirconium oxide, and superheated the stones with the addition of stabilizing oxides to created cubic minerals they believed at the time to be diamond.  What they had actually created was cubic zirconium (CZ), which would not gain fame until the late 1970s, when Swarovski & Company began mass-marketing the crystal in its jewelry. By 1980, global production of cubic zirconia had already reached 50 million carats a year.

Not to be forgotten, De Beers has been a major player in the development of synthetic diamonds since as early as 1946, when Sir Ernest Oppenheimer established Industrial Distributers Ltd. to focus on finding new industrial uses for natural diamond. At the time, he was looking for new uses for many of the low-quality diamonds coming out of De Beers mines, which were essentially useless, and commanded practically no value. By 1960, IDL had developed its own methods for HPHT diamond synthesis from its operations in South Africa. By 1989, they were successful in growing diamonds using CVD. In 2002, the company rebranded itself as Element 6, in reference to carbon, the sixth element on the periodic table. Element 6 is now one of the largest synthetic diamond companies in the world, both from a production standpoint, and as a research unit exploring new processes for development and industrial applications.

Lab-grown diamonds clearly have a long and interesting history. Next week I will take a closer look at the ways in which diamonds can be synthesized in a laboratory, including some new developments that may change the game for the future.

      The views expressed here are solely those of the author in his private capacity. No one should act upon any opinion or information in this website without consulting a professional qualified adviser.