There are many questions surrounding diamonds, especially among first-time jewellery buyers. As you research online, perhaps for an engagement ring, you may have seen much information about naturally formed diamonds versus lab-grown diamonds. To ease your confusion and make sure you make the best decision when purchasing your diamonds, we will discuss what a diamond is, how they are created, the types of diamonds, the differences between the diamonds, and diamond alternatives. We hope that after reading this, you'll be confident that your diamond will last a lifetime.
What is a diamond?
Diamond is the hardest, most stable form of pure carbon. This solid elemental form of carbon has its atoms arranged in a crystal structure called diamond cubic. Diamonds are renowned for their hardness. Measured by the resistance to scratching, diamond is the only substance able to scratch diamonds.
How are they made?
Naturally formed diamonds are created when pure carbon undergoes exceptionally high temperature and pressure over billions of years within the earth's mantle (80 – 120 miles deep). They are then brought to the surface in rare molten rock over aeons of violent volcanic eruptions.
Not all organic diamonds are created the same, with colour, size, and clarity differences. These differences are caused by minerals and other conditions influencing the diamonds as it grows. For example, diamonds with a yellow hue are caused by trace amounts of nitrogen, and trace amounts of boron cause blue diamonds.
Lab or man-made diamonds are made under similar conditions to natural diamonds but in highly controlled laboratory settings. A common misconception is that lab-grown diamonds are 'fake' or 'synthetic' diamonds; this is not true.
Lab-grown diamonds have essentially the same chemical composition, crystal structure, and optical and physical properties as naturally formed diamonds. There are two categories of lab-grown diamonds:
High Pressure, High Temperature (HPHT) - laboratory-grown diamonds produced in laboratories that mimic the earth's high pressure, high-temperature conditions of natural diamond formation. HPHT diamond growth occurs at pressures of 5–6 GPa (roughly equivalent to the pressure exerted by a commercial jet airplane if balanced on the tip of a person’s finger) and at temperatures of 1300–1600°C.
Chemical Vapour Deposition (CVD) - laboratory-grown diamonds using moderate temperatures (700°C to 1300°C) and lower pressures. Carbon-containing gas is pumped into a vacuum chamber, depositing onto a diamond seed and crystallising as a laboratory-grown diamond.
The Difference between Natural and Lab-Grown
When considering the similarities and differences between natural and lab-grown diamonds, you won't find any discrepancies with the naked eye when comparing a diamond from each with identical characteristics of the 4 C's (Colour, Cut, Clarity, and Carat). However, there will be internal differences that trained gemologists can see using 10x magnifications. This is down to the environmental differences between natural and lab-grown diamonds.
Both lab-grown and natural diamonds will have inclusions (not visible to unaided eyes) except in sporadic cases where natural diamonds emerge in perfect conditions. Lab-grown inclusions are usually metallic due to the metallic solution they're formed in. These do not occur in natural diamonds.
Naturally formed diamonds include inclusions caused by all the
elements and violent volcanic eruptions it endured to get to the surface. Every diamond gets a clarity rating by a professional lab (we use GIA and IGI). These ratings signify how noticeable the inclusions are within diamonds. Natural and lab-grown have different rating systems.
As previously mentioned, the colour of natural diamonds is determined by a trace amount of elements that become trapped inside the diamond lattice as it grows. Therefore, natural diamonds can come in an infinite number of hues, saturation, and tones.
On the other hand, lab-grown diamonds are produced in several colours (yellow, blue, pink, green, and white) with varying colour grades. Sometimes these are then colour treated to enhance the colour through HPHT. Alongside improving the colour, lab-grown diamonds can also be treated to be de-colourised. This is often the case in CVD lab-created diamonds, which come out brown and are then de-colourised to be colourless or near colourless.
Regarding the price difference between natural and lab-grown diamonds, lab-grown are generally 30% cheaper in price than natural diamonds with the same 4 C's. The majority of this price difference is due to the rarity factor involved with natural diamonds. Lab-grown diamonds are usually created in 6 – 10 weeks. When you compare that to natural diamonds close to the earth's surface, created 1.1 – 3.3 billion years ago, there's a vast difference. Natural diamonds are therefore an artefact, making them a pretty special thing to wear as jewellery.
It is important to note that if your emphasis is not primarily focused on the resale value of a diamond, then Lab-grown diamonds are a fantastic route. Lab-grown diamonds don't generally hold the same resale value as a natural diamond, but they offer more bang for your buck. The resale value is not the same because natural diamonds have been bought and sold for hundreds of years, creating an established market. Lab-grown diamonds are a relatively new thing, so although there's a demand there, they do not match up to a natural diamond's resale value.
While researching diamonds, you may have encountered words such as 'synthetic' or 'simulant' diamonds. These are different to both natural and lab-grown diamonds as although they look similar to diamonds, they have very different chemical and physical properties. Many fantastic alternatives to diamonds look like and can work as substitutes for diamonds; however, it's important to note that these do not share the durability and sparkle that diamonds offer. Some of these alternatives are: