Lab Grown Diamonds

Today we’d like to dispel some myths and help you make a better-informed decision when it comes to selecting a new diamond for your engagement ring. The skyrocketing popularity of gem-quality lab grown diamonds in the last five years has shaken up our industry and provoked enthusiastic debate among jewellers. In short, we welcome these stones and the level of innovation that made them possible — but there are some common misunderstandings about lab grown diamonds that need to be cleared up.

When people hear about lab diamonds they often assume that the stones are somehow 'fake' or substandard compared to a diamond that is mined from the earth in the traditional way. That’s a huge misconception. In fact, lab grown diamonds are identical to mined diamonds in almost every way. They are made of crystallised carbon, meaning they have the very same chemical, optical, physical, and thermal features — while also being cut to the same high standard.

Even industry experts struggle to tell the difference without the use of highly specialised equipment to scan for crystal patterns and irregularities. People are often surprised to learn that lab grown diamonds generally test positive on a diamond tester.

There are two methods to grow diamonds; the HPHT (high-pressure high temperature) method, and the CVD (chemical vapour deposition) method.

HPHT was the original method. It involves heating carbon to extreme temperatures (up to 1500 degrees Celsius) and applying pressure of approximately 1.5 million pounds per square inch. Technicians create lab grown diamonds from 'seeds,' or tiny diamond fragments. A complex mix of gases is directed at the seed under these conditions, causing the diamond to gradually develop, atom-by-atom until it emerges as a perfect gemstone.

Industrialists valued these stones for their hardness and conductivity. The early prototypes were not as large or as clear as the best mined diamonds, and most were coloured yellow or brown due to the nitrogen that was used for stabilisation.

By contrast, the Chemical Vapour Deposition (CVD) technique involves the use of a sealed, airless chamber heated to around 800 degrees Celsius. The chamber is pumped full of ultra-pure carbon-rich gasses like hydrogen and methane. Carbon atoms in the gas separate and descend onto a thinly sliced diamond substrate, building up layers to form a rudimentary diamond crystal.

These stones take six to ten weeks to reach maturity. The diamond seed is cut by laser from the crystal, so that it can be reused to grow more diamonds.

A lab grown diamond is most definitely not to be confused with a diamond simulant! The latter type of stone is not carbon-based; it is simply manufactured to look like a diamond, even though it is made from altogether different materials like cubic zirconia or moissanite.

Cubic zirconia is produced from zirconium dioxide. It’s very inexpensive, so it’s often used in cheap rings and costume jewelry. It discolours and scratches easily, so it’s not a compelling diamond alternative.

Conveniently for the discerning shopper, lab-created diamonds are certified using the same system and standards as mined diamonds. This means they are individually graded on Cut, Colour, Clarity, and Carat Weight.

They are an exciting option if you are looking for an affordable alternative to natural diamonds — prices are typically 20-40% lower than for naturally-mined stones.

The absence of supply constraints does mean that their value will depreciate over time, affecting their resale value. However, these lab-made stones have the same lifespan and the very same sparkling finish as their natural equivalents, so you are not compromising on brilliance or quality.