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reports2023/01/13

Lab-Grown vs Natural Diamonds: What's The Difference?

by Alexandra Morris Robson

Alexandra Morris Robson is CEO and founder of Augustine Jewels, a luxury British Jewellery brand using traditional design techniques and hand-selected gemstones. She explains what lab-grown diamonds are and how they are both fundamentally similar to and different from naturally mined diamonds.

What are lab-grown diamonds?

There’s a change in the air in the world of diamonds. Recently the diamond market has been flooded with lab-grown diamonds. These are diamonds that are 'grown' in a laboratory in a process that mirrors that of the natural world over millions of years. Thus, lab-grown diamonds are, in their molecular structure exactly the same as 'natural' diamonds.  Both have the chemical formula C for carbon. Lab-grown diamonds are not therefore 'fake’ but they are actual diamonds. The fact that they are structural diamonds, makes it very difficult to distinguish them from natural diamonds — a very high calibre microscope and much expertise are needed to distinguish lab grown from natural. 

How much do lab-grown diamonds cost?

Lab-grown diamonds are about one-third to one-half of the price of a natural diamond and have therefore become quite popular! Some people also say that lab-grown are more “ethical” since they do not involve mining. 

How are lab-grown diamonds made? 

There are 2 methods for making diamonds in a lab – one method is called high-pressure, high-temperature (HPHT) and the second is called chemical vapour deposition (CVD) diamonds. Personally, I find HPHT diamonds better than CVD, but it can depend on the manufacturer. 

What are synthetic alternatives to lab-grown diamonds?

There have for a long time, been synthetic replacements for diamonds. Cubic Zirconia is a well-known diamond substitute. It looks completely different under a basic microscope and is easy to spot. Another synthetic is moissanite. Again, it is structurally different to a diamond. Synthetic moissanite is more expensive and better looking than CZ. 

What are natural alternatives to lab-grown diamonds?

There have also been, for many years, natural replacements for diamonds. White topaz and white sapphire both make very pretty and natural alternatives. They lack the sparkle and strength of diamonds, but they can be a lovely natural alternative. There is also naturally occurring moissanite. Moissanite is a naturally occurring silicon carbide and its various crystalline polymorphs. It has the chemical formula SiC and is a rare mineral, discovered by the French chemist Henri Mossian in 1893. But moissanite on the market is usually more synthetic than natural

How are lab-grown diamonds graded?

Lab-grown diamonds are graded in exactly the same way as natural diamonds. This is commonly known as the 4 Cs of diamonds. They are: 

Colour – this is the colour of the diamond. The best diamonds are graded colour D and the worst Z. If you are wondering what happened to A, B and C, well, when the GIA (Gemmological Institute of America) started the grading system, there were so many existing systems using the letters A, B and C that they decided to start afresh making D the best colour. A D-coloured diamond would actually have no colour at all. A Z colour would be quite tinted yellow. At around colour grade H, you can start to see a tinge of yellow. Most top jewellers would not sell beyond grade G. 

Clarity – this is a definition of how clear a diamond is. The best diamond would be IF — Internally Flawless. These stones are really used for investment purposes. The next would be VVS1 or Very, Very Slightly Included, then VS, Very Slightly Included and then the next SI or Slightly Included. Most top jewellers stop at SI and would not sell beyond that point. A diamond which is the next level, I meaning Included, would have marks inside that would be visible to the naked eye and therefore would not be very appealing.

Carat – this is the weight of the diamond. The larger the weight, in general, the more expensive the price.

Cut – this not only refers to the type of cut and shape of the stone but also to the quality of the cut. So for example, the shape of the stone might be pear, square, octagon, cushion, radiant, Asscher or round. However, the cut refers to the quality of the cut. Excellent is the best cut, and good, well it’s good enough. The cut also considers how symmetrical the cut is. 

Are lab-grown diamonds more ethical?

This debate is raging – some people say that lab diamonds are more ethical and responsible as they do not involve digging large pits, mining a finite resource, potentially exploiting labour or transporting diamonds. Others say that the amount of energy and resources used to create the diamonds in a lab is too extreme. When fossil fuels are used, GHG emissions for lab-grown diamonds can be up to three times that of mined diamonds, according to a TruCost Report. However, new systems are reducing the energy required and switching to clean energy that significantly reduces its impact, so it looks like lab-grown diamonds are here to stay. 

So should you buy lab-grown or natural diamonds?

So, what is a girl to do? We have only ever used natural gemstones and diamonds and would never make anything in CZ or moissanite. But we are thinking of using lab-grown diamonds in our next collection. The price, ethics and beauty are making us think again! It’s a big debate. 

Our advice would be — if it is a special piece, such as an engagement ring or a 40th birthday then buy natural. If it’s a Valentine's Day gift, maybe you could look at lab-grown diamonds?