Natural Diamonds are one of the oldest, hardest and most coveted materials on Earth. So how do they compare to lab-grown Diamonds and Moissanites?
How old are natural Diamonds and how do they form?
Diamonds are one of the most unique and special materials in the world, and for so many reasons. Not only have they been one of the most coveted treasures since the 4th century BC and throughout history, they are known as the hardest material on Earth, as well as one of the oldest.
All natural, Earth-mined Diamonds are between twenty million and two and a half billion years old! After forming in the upper mantle of the Earth, about 140 metres below the Earth’s surface, they get pushed to the surface in magma and a rare combination of extreme heat and pressure. In reality, most of the world’s diamonds never make it to the Earth’s surface at all. Plus, If any change of pressure occurs during this process, the pure carbon of the Diamond will simply convert into a graphite-like material resembling pencil lead. The process of a Diamond forming in the Earth over millions to billions of years and finally making it to the surface in one piece, especially as a glittering, colourless specimen of high clarity (or even rarer, in a fancy colour!) is truly a magical and rare occurrence.
What are lab-grown Diamonds?
Lab-grown Diamonds were first created by scientists in the 1950s and were originally used for industrial purposes due to their excellent hardness and ability to cut and polish other materials. Lab-grown Diamonds have the same all-carbon chemical structure and composition as natural Diamonds. However, instead of being created naturally in the Earth through millions of years of heat and pressure, it is now possible to re-create that same process scientifically, sometimes in a matter of weeks. The original method for creating a lab-grown Diamond was referred to as High Pressure High Temperature (HPHT), which re-creates the very high heat and pressure environment required for a Diamond to form, and is also sometimes used to colour treat natural Diamonds.
In the early 2000s, lab-made Diamonds were also created using the Chemical Vapor Deposition (CVD) method, which still requires very high temperatures (up to 1130° celsius) but lower pressure. During this method, carbon-rich gas is used to build a Diamond crystal one very thin layer at a time.
Can anyone tell the difference between a natural Diamond and a lab-grown Diamond?
So, are there truly any differences between a lab-grown Diamond and a natural Diamond? And, perhaps most importantly, can someone tell whether you're wearing a lab-grown Diamond? The chemical and physical structure of a natural Diamond and a lab-made Diamond are identical. In fact, one of the only ways to identify a lab-grown Diamond with the human eye is potentially through it's lack of inclusions and other imperfections!
What are Diamond testers and how do they work?
Diamond testing machines used by jewellers or others in the trade, and sometimes seen on social media, are actually testing for trace amounts of nitrogen. In general, nitrogen is only found in natural Type Ia Diamonds, which accounts for approximately 90% of Diamonds on the market. Most lab-grown Diamonds fall into the highly sought-after Type IIa category, which means they don't usually contain nitrogen, the element which causes the colour Yellow in both Diamonds on the D-Z scale, and fancy Yellow Diamonds. Thus, contrary to popular belief, Diamond testers can't immediately identify lab-grown Diamonds—only that they are not Type Ia, which means that they could be a very rare, natural Type IIa, or lab-grown.
What is the difference between Diamond and Moissanite?
Diamond simulants appeared on the market as early as the 1700s and were usually made of glass, and sometimes backed by foil or metal to create extra colour and more realistic sparkle. Due to their lower hardness level, Diamond simulants (which refers to any material used to look like a Diamond) generally have a softer lustre, more rounded-looking facet edges, and can get scratched much easier. They also have lower thermal conductivity (they get much hotter faster when exposed to heat versus Diamonds which are always cool to the touch) and higher specific gravity, which means they’re usually much heavier than they look. Of course, one of Diamond’s most unique and special traits, it’s fire and dispersion, is what sets it apart from almost all other gemstones, and what definitely sets it apart from simulants. Both attributes contribute to Diamond’s trademark sparkle and ability to break white light into bright white flashes and rainbow colours.
Now, simulants have come a long way, with two of the most popular currently being Cubic Zirconia and Moissanite. Natural Moissanite was actually discovered in the United States in 1893 by Nobel Prize winning chemist Dr. Henri Moissan. He discovered its tiny crystals when analyzing meteorites in Arizona. While both Cubic Zirconia and Moissanite can occur as natural minerals, they are both very rare on Earth, and so all gems found on the market today are lab-made. One of the biggest tell-tale signs of Moissanite, which is made of silicon carbide versus the pure carbon of Diamond, is that while it's generally a bit darker in appearance, it actually has more fire than Diamond and is doubly refractive, which means it displays far more spectral (or rainbow) colours when you look at it face-up, and the appearance of its facets will look “doubled.” Some may find themselves especially attracted to this high-wattage and eye-catching sparkle. Cubic Zirconia remains another popular Diamond simulant and has been on the market since the 1970s. Softer than both Moissanite and Diamond, CZ is prone to scratching, and develops a ‘hazy’ look over time.
Moissanites can also be excellent pieces for use in travelling, surprise proposals, promise rings, and of course, for generally getting the look of a rare and priceless Diamond for a very budget-friendly price.
Wondering which form of Diamond is considered the most sustainable? Read about Sustainable Jewellery here.