Hong Kong's home of lab made diamond jewellery
Where It Began
Scientists initially discovered that diamonds consist of pure carbon in 1797. At this point, the mission began to try to create a synthetic diamond. During the 1900s, scientists made an effort to replicate the conditions needed for diamonds to form within laboratory settings. Many attempts were made, but none succeeded.
1954: Early Break-Through Success
In December of 1954, the first ever proven synthetic diamonds were made by GE (General Electric) in their laboratories as a part of a project named “Project Superpressure,” which initially commenced in the 1940s but was delayed due to the second world war. Scientists experimented for years with different temperatures, pressures, and methods to create diamonds from carbon. They used a high-pressure belt press to subject tiny seed crystals to 1600 degrees Celsius and 100,000 atmospheric pressure. Within the belt press, graphite (made purely from carbon) was dissolved in metals such as nickel, iron, and cobalt to fast-track the transformation of graphite into diamonds.
The scientists believed they had finally succeeded when the finished material broke their cutting tools. With a Mohs hardness of 10, diamonds can scratch and even destroy metal tools. They then confirmed that they had, in fact, managed to create diamonds.
The diamonds created through this process were used for industrial purposes as they were too small to be used as gems. Regardless, this laid the foundations for GE to finally create gem-quality crystals in 1971. This process involved adding heat and pressure to a graphite seed in the center using a tube until it eventually developed into a diamond.
Even though this was a significant discovery, utilizing such high temperatures to produce these gems proved too expensive to compete economically with natural diamonds. These early gem-quality lab-produced diamonds were frequently yellow and contained many inclusions, meaning they would struggle to receive high grades according to color and clarity standards for colorless diamonds.
Improvements: Closer to Perfect
Further research uncovered that an excess of nitrogen caused the yellow color in these stones. After making some amendments, the teams were finally able to produce colorless diamonds. A few decades later, research carried out by scientists in the USA, China, and Russia made it possible for these lab-created diamonds to reach large sizes. It was from this point that these stones entered the diamond market.
Production Methods
GE's original method, a high-pressure/high-temperature process, is commonly known as HPHT. This process replicates the conditions that form diamonds underground within the earth.
Nowadays, most lab-grown diamonds (including ours here at Lab Grown Diamonds Centre in Hong Kong) are made using a process called chemical vapor deposition or, in short, “CVD”. This consists of a natural diamond seed being heated by carbon gas in a chamber, resulting in the carbon sticking to the seed and growing into a larger diamond. CVD enables scientists to have greater control over specific properties of lab-grown diamonds and allows for producing large gem-quality diamonds. The chemical vapor deposition method can also be carried out at lower pressures and temperatures, making it much less expensive.
Although the first patent for CVD was issued in 1950, the process wasn’t perfected to produce gem-standard diamonds until the 1980s. Even more, time was required for this process to become commercially practical, as only one diamond seed could go through CVD at a time. At the time, this was very costly, most likely tens of thousands of dollars to produce each diamond.
The Takeoff
Lab-grown diamonds took off around 2013 and 2014 when the movement for sustainability and ethical sourcing became stronger.
Since 2018, the Federal Trade Commission has recognized lab-made diamonds as real diamonds. Fast-forward to today, and lab-grown diamonds have exceeded 30 carats in size. With technology becoming more advanced daily, opportunities are becoming more and more limitless when it comes to lab-grown diamonds.