My systematic involvement with synthetic diamonds started 8 years ago during which I have been travelling constantly. I attend relevant conferences and am a guest at research centres in Europe, the most important of which is the De Beers research centre. At the same time I train in the identification of synthetic diamonds, both in bonded jewellery and loose stones, gemologists and jewellery appraisers in many countries, including Austria, Italy, Spain, Cyprus, Cyprus, UK and USA.
More and more often I receive more specific questions about the origin of diamonds, mineral or laboratory. After all, this is a procedure that has been added to the IGLcert diamond testing protocol anyway, as we have been detecting synthetic diamonds since 2016. In fact, at my conference in Athens in 2015, the largest synthetic diamond in the world was presented, surprising the audience.
The purpose of the article is to clarify the picture between minerals and synthetic/lab-grown diamonds and to highlight their similarities and differences, both at the laboratory and commercial level.
So let's first clarify the difference between a mineral diamond, a synthetic diamond and an imitation diamond. A mineral diamond is one that has been created 2.5 billion years ago in the upper mantle of the earth and has come to the surface through volcanic activity. The diamond deposit is not renewed but to this day we are still discovering deposits that were created during that period.
In contrast, the synthetic diamond has been created in a laboratory. It carries the same chemical composition and physical properties as the mineral diamond. Synthetic diamond reserves are unlimited as they are produced in laboratories with unknown production volume per unit. Finally, imitation diamonds are stones that have no relation in terms of chemical composition and physical properties to diamond but attempt to imitate it visually. Classic examples of imitations are cubic zirconia (zircon) and moissanite.
“The most important thing for me is to be absolutely clear to the consumer what exactly they are buying; how exactly it is with jewellery set with zirconium or synthetic ruby for example.”
Their composition
Synthetic diamonds are not a new product. Crystallization efforts began in 1797, when it was discovered that diamonds are mostly composed of carbon. Since then, there have been several attempts that usually resulted, if they did, in the creation of nanocrystals of diamond that could not be exploited. It was also very difficult to confirm the success of the crystallization, as all experiments used mineral diamond as a seed.
Efforts were made in 1953 by the Swedish power company ASEA, which succeeded in crystallizing synthetic diamonds in the laboratory. But due to their small size, they could not be used in jewellery making. Their effort was not announced until 1980 and ASEA lost the lead to General Electric. The latter managed to create synthetic diamonds of a satisfactory size in 1970. Their continued efforts to create them and the advancement of technology has brought us to the present day. Thousands of companies around the globe now crystallize synthetic diamonds. For industrial use, but also for use in the jewellery industry.
Regarding the technical part, there are two methods of crystallizing synthetic diamonds. These are the high pressure and high temperature method ( HPHT - High Pressure / High Temperature ) and the chemical vapour deposition method ( CVD - Chemical Vapor Deposition ).
More specifically, the HPHT method simulates the high-pressure and high-temperature conditions that the diamond crystallized in the depths of the earth. A “seed” of synthetic diamond is placed in carbon and exposed to high pressure and high temperature. The carbon then melts and begins to crystallize around the seed, creating a larger synthetic diamond. Theoretically, the longer the process takes, the larger the synthetic diamond will result. There are of course several technical limitations to this. The largest synthetic diamonds in existence today have been created using this method.
In the CVD method, a “skin” of synthetic diamond is used as a “seed”. Usually this “seed” is another synthetic diamond created by the HPHT method. It is then placed in a chamber and heated at a relatively low temperature. Nitrogen-rich gases are then added to the chamber. The gases create a plasma around the “seed”. The resulting pure carbon crystallises in layers on the surface of the seed crystal.
Synthetic diamonds of larger size, but also very small ones are usually obtained by the HPHT method. While for the other sizes the CVD method is used. For all larger sized synthetic diamonds (above 0.20ct) most gemological laboratories issue gemological reports describing the 4Cs (weight, clarity, cut, coloration).
As with mineral diamonds (some laboratories use the same criteria with variations of category names). They make sure that it is easily and immediately distinguishable that these are laboratory developed diamonds. Either by the colour and title of the form, or by the description inside it (Laboratory Grown Diamond).
With regard to small size diamonds (Melle), we at IGLcert thoroughly examine whole batches of diamonds for the presence of synthetic diamonds before they are set into jewellery. As well as every tied jewel that enters the lab for testing and issuing a gemological report.
The technology around synthetic diamonds has developed rapidly in recent years. It allows hundreds of companies to produce ever larger quantities in a much shorter time. Better quality than in the past, but also at a lower cost. Today CVD synthetic diamond production is estimated to cost 300$ - 500$ per carat. As opposed to 4.000$ per carat in 2008 ( Source: Antwerp World Diamond Center ). This has created competition between lab and mineral diamond supply companies. While both sides have listed their arguments corresponding to their interests, some of which will be analyzed below.
Synthetic Diamonds and Jewellery
Several years ago, laboratory diamonds had almost the same value as minerals. In some rare cases even higher. Today, and as production increases and competition grows, the value of synthetic diamonds is decreasing. Central to this was the creation of Light Box, a subsidiary of De Beers. One of the largest mineral diamond distributors, which set a new standard in the jewellery industry.
Light Box retails lab-grown diamonds at a much lower price than minerals. At 800$ per carat, one can buy earrings or pendants in silver or low carat gold set with lab developed diamonds. The carat weight of the stones offered by Light Box starts from 0.25ct and goes up to 2.00ct staying at the same price per carat. The company does not offer rings (solitaire stones), aiming for the inexpensive everyday gift. And not to replace the jewellery offered at more important moments in the consumer's life. The move has caused a rapid drop in the prices of synthetic diamonds, both strung and unstrung, at wholesale and retail. Nevertheless, several companies have included jewellery with synthetic diamonds in their collections (Swarovski, Pandora, etc. ).
The trend, therefore, is for synthetic diamonds to be available in the most everyday jewellery. The most important thing for me is that the consumer should be absolutely clear about what they are buying; just as is the case with jewellery set with zirconium or synthetic ruby, for example.
That's it for the use of diamonds in jewellery making. Because as far as the industrial use of diamonds is concerned, the winner is undoubtedly synthetic diamonds. It is known that about 30% of mineral diamonds are used in jewellery making and 70% in industry. Films of synthetic diamonds of minimum thickness are used in the industry. From mobile phones to medical devices and car engines. Reducing losses during charging, cooling circuit boards. But also reducing engine wear, while minimising emissions.
Environmental Factors
In recent years there has been much concern about the energy footprint of all human activity on the planet. Taking it for granted, as far as the diamond industry is concerned, that both synthetic and fossil diamonds leave an energy footprint. Let us examine the claims of both mining companies and diamond production companies.
Most, if not all, laboratory diamond companies label their product as environmentally friendly. Few, however, provide evidence to support their claims. This is why the FTC ( Federal Trade Commission ) in the US has advised them to be particularly careful in their eco-friendly claims.
It is taken for granted that to crystallise a synthetic diamond, like mining a mineral, energy is required. However, how much energy is required in each case remains a mystery. There is some aggregate data from the diamond mineral industry. There is no corresponding data from the synthetic diamond industry collectively. Only individual data from some companies. However, the main claim of synthetic diamond producers remains that they do not mine, so they automatically become environmentally friendly.
At the same time was conducted research by the NDC (Natural Diamond Council), whose members are the 3 largest mining companies (De Beers, Alrosa, Rio Tinto). It was claimed that, because synthetic companies operate in countries where the main source of energy comes from coal or natural gas, Carbon Dioxide emissions are 3 times higher than those of mineral diamonds. (For example, 160 Kg for each carat of mineral diamond and 511 Kg for each carat of synthetic diamond).
In fact, both industries use huge amounts of iron (a mining product). One in the heavy mining machinery, the other in the presses that crystallize synthetic diamonds. In the first case we have a certain amount of equipment. In the other, an unknown number of companies producing synthetic diamonds, and therefore an unknown number of presses.
Humanitarian Agentsς
After the film “The Blood Diamond” was shown, the diamond industry was accused of using unethical practices. It was found that armed groups during the civil war in Sierra Leone had been financed by the sale of diamond minerals. A charge that is still being pursued today. The diamond industry in collaboration with the United Nations created in 2003 a body for the control and transparency of diamond sources called the Kimberley Process. So that it is impossible to traffic diamonds coming from war zones, mines employing children or any other unethical situation. The civil war in Sierra Leone has been over for almost 20 years. The Kimberley Process appears to have successfully yielded 99.9%, so the issue of blood diamonds is probably considered closed.
All of the above was used in support of the synthetic diamond industry, emphasizing that their sources are legal and no violence is used in the closed production facilities. Assuming that this is the case, I don't know how ethical it is for one industry with no real advantage (obviously no violence anywhere) to try to dramatically reduce the other's production. Depriving basic livelihoods (shelter, food, health care, education, etc.) to communities that make their living solely from working in diamond mining.
Conclusion
The issue is multifaceted and complex. Given that it will be several years before there is accurate data from both sides, I believe that for the time being both industries are trying to reduce their energy footprint. The reason is simple, because in doing so they are also reducing their energy costs. As energy consumption equals capital consumption, it is also in their interest to do so economically. Companies or people may be or have been greedy, immoral or even violent, diamonds never.
By George Spyromilios
Adamantologist
