Are lab-grown diamonds our new best friend?

05 September 2023

Jewellery expert Mary Collins from Mappin & Webb tells us about laboratory-grown diamonds; their increase in popularity, how they differ from natural diamonds and what you and your clients should be aware of.

Large gemstone held in tweezers


Jewellery designers, luxury brands and many famous people including royalty are embracing lab-grown diamonds (also known as synthetic). Why? They have the same chemical make-up, physical and appearance qualities as natural diamonds, are quicker and arguably more ethical and environmental to produce and are far cheaper. Lab-grown diamonds sell for 30%-40% less than their natural counterparts.

The desire to produce lab-grown diamonds dates back to the 1700s but it wasn’t until 1971 that the first gem-quality diamond was created. The process was too expensive, low quality and wouldn’t meet the high grades in the four C’s to compete with natural stones (cut, carat (size), colour and clarity). Since then, the process has been refined and we now have gems officially recognised as diamonds and available on the market.

What are laboratory-grown diamonds?

Both natural and synthetic diamonds are formed of the same material - pure carbon. However, whereas natural diamonds have ages between 1 billion and 3.5 billion years and are formed at depths between 150 and 250 kilometres (93 and 155 miles) in the Earth’s mantle, lab-grown diamonds are produced in a matter of weeks in a laboratory.

The most current popular methods used to create lab-grown diamonds are known as HPHT (High Pressure High Temperature) and CVD (Chemical Vapour Deposition). The properties of a lab-grown diamond depend on the manufacturing process. However, some lab-grown diamonds have properties such as hardness that is superior to those of most naturally formed diamonds. Both CVD and HPHT diamonds can be cut into gems and various colours can be produced: clear white, yellow, brown, blue, green and orange.

Well-known jewellery companies are investing in lab-grown diamonds

Global reserves of natural diamonds are depleting. This has in-part driven the eagerness for lab-grown gems on a grand commercial level. De Beers, the world's largest diamond miner, launched its own synthetic diamond brand Lightbox Jewellery in 2018. Diamond Foundry has just announced their proposed factory in Spain, due to start production in 2024, will be able to produce up to 10 million carats of industrial and gem crystals annually. Watch companies such as Tag Heuer have launched new models using lab-grown diamonds and Breitling has vowed to phase out mined diamonds by 2024 citing a more sustainable production.

Identifying synthetic diamonds

Because laboratory-grown diamonds are essentially chemically and optically the same as their natural counterparts, traditional gemological observations and old-style “diamond detectors” are not able to tell them apart.

Most natural diamonds have internal flaws that occurred during the stones’ formation, synthetics tend to be cleaner. This is because they are created through a controlled process designed to minimize defects, and as a result, there are fewer flaws in the crystal structure of synthetics.

The only way to tell them apart is with specialist equipment often meaning the gem would need to be sent away for analysis. However, the majority of lab-grown diamonds over 0.20ct should be supplied with a certificate from a recognised authorised independent gemmological laboratory such as Gemological Institute of America (GIA), International Gemological Institute (IGI) and Gem Certification and Assurance Lab (GCAL). A certificate attests to the gem’s origination, quality and characteristics. Just as natural diamonds are examined and graded on their attributes, so are created diamonds (and you would expect a similar certificate for a natural diamond).

What does this mean for your high net worth client?

Lab-grown diamonds are becoming more readily available and with natural diamond reserves depleting and the difference between the two almost impossible to tell apart, proving the value of the diamond you own is ever more important. A 1-carat lab-grown diamond might be worth c.£6,750 whereas a 1-carat natural diamond could be worth c.£26,000 – a huge difference. It’s not difficult to see why over 50% of jewellery and watches are expected to be underinsured1. As a result, insurers may require documentation (certificate) before adding diamonds to a policy or accepting a claim. 

Why worry? With the rise in the cost of living, the risk of a high net worth individual being targeted for theft is a rising concern so being vigilant and protecting valuables is all the more important.

Ecclesiastical recommends these three top tips:

  1. Ensure that any jewellery, watch or item with diamonds is regularly valued and insured appropriately, whether natural or lab-grown
  2. Gain an authorised certificate, seek a trusted analysis from an approved valuations company that will provide a clear description of the item, materials and stones used, the cut, colour, clarity and carat
  3. Ensure that your jewellery and watches are stored in an appropriate cash rated safe and the safe has been installed by an approved and recognised Safe installer.

1 Ecclesiastical research 2023 of 119 brokers who place HNW business.

Other data provided by the author, Mappin & Webb.

About Mappin & Webb

Mappin & Webb is a true British treasure with over 240 years of tradition and historical significance in the world of silver and fine jewellery. Renowned for combining timeless craftsmanship with superior quality and contemporary design, we have produced exquisite fine jewellery, elegant silverware, watches, glassware and the unique lifestyle accessories that have long been at the heart of affluent British society.

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