The Difference Between Lab-Grown and Natural Diamonds
Whether you're planning to propose or just looking for an amazing piece of jewelry for yourself, it's important to understand the difference between lab-grown and natural diamonds. Lab-grown diamonds, also known as synthetic or cultured diamonds, have become increasingly popular over the past few years. While both natural and lab-grown diamonds share the same physical, chemical, and optical properties, Lab-grown diamonds are made in factories and natural diamonds are mined from the earth. In this blog post, we'll explore the differences between lab-grown and natural diamonds to help you make an informed decision about which is the best option for you.
The Creation Process
Natural diamond crystal
When discussing the difference between lab-grown and natural diamonds, it's important to understand how each type of diamond is created. Natural diamonds are the result of a process that occurred millions of years ago deep within the Earth’s mantle. Over time, immense heat and pressure forced carbon atoms to arrange in the packed diamond crystal structure. These precious stones then made their way to the surface through a kimberlite pipe, a very specific type of volcano.
Lab-grown/synthetic diamond crystal
Lab-grown diamonds, on the other hand, are created in factories using the same process that occurs beneath the Earth's surface. A diamond seed along with carbon powder (usually super pure graphite) is placed inside a chamber and exposed to extremely high temperatures and pressures. The result is a replica of a natural diamond that is chemically and optically identical. This technology, named HPHT (High Pressure – High Temperature) was the first one used and has made it possible for us to recreate diamonds in a fraction of the time it takes for nature to produce them. Another method developed later but recently more used is the CVD (Chemical Vapor Deposition). The process takes place inside a reactor chamber where in a fraction of the atmospheric pressure a plasma torch ionizes methane gas which releases Carbon atoms. Those atoms precipitate on a disc on which a number of synthetic diamond seeds are placed. CVD diamonds grow layer by layer without the need for extreme pressure like in the HPHT process making the method more economically viable and easier to control since it takes place in a closed space where chemicals can be used to dope the crystals.
Chemical Composition
The most important classification of natural diamonds from the chemical point of view has been made in the 1930s defining 2 types of diamonds, depending if Nitrogen is present as an impurity or not. Later the classification evolved with new subcategories but still, the most common type of diamond contains Nitrogen in several states of aggregation. When Nitrogen is present as an impurity in a single atom form, so not aggregate, the diamond exhibits a saturated yellow canary color. Until a few years ago the lab-grown diamond production was almost completely yellow since it was not possible to get rid of the single nitrogen impurity. More recently it has been possible to synthesize colorless diamonds with the development of “Nitrogen-getter” elements which avoid the contamination of the crystal lattice during its growth. Essentially it was this improvement in the growing methods that allowed the availability of colorless crystals in large quantities. They are all type IIa (meaning without nitrogen impurities).
Despite the presence or not of nitrogen impurities, Lab-grown diamonds and natural diamonds have the same chemical composition. Both are made of carbon atoms arranged in a crystalline lattice structure. The only difference between lab-grown diamonds and natural diamonds is their origin.
Lab-grown diamonds are identical to natural diamonds in terms of physical properties such as hardness, sparkle, and durability but are created in factories using advanced technology and processes which usually last not more than a few days.
Natural diamonds formed deep within the Earth’s mantle under extreme temperatures and pressures through a process that can take over millions of years. Subsequently, the diamonds were raised to the surface through volcanic eruptions. This chain of events is unique in our planet’s history and cannot happen anymore. As a result of their long journey from the Earth’s interior, natural diamonds may have unique inclusions that are sometimes extremely useful to understand the complex geologic process that characterized our planet's history.
No matter if a diamond is lab-grown or natural, besides the minor differences due to impurity traces they will always contain the same elemental makeup. Lab-grown diamonds are 100% real diamonds with the same physical, chemical, and optical characteristics as natural diamonds.
Physical Characteristics
Although lab-grown diamonds and natural diamonds may look similar to the naked eye, they are not identical. The biggest difference between the two is the nature and shape of the inclusions. While there is a large number of different types of inclusions that can be embedded in a natural diamond, the ones featured in synthetic are relatively less and can be diagnostic at the microscope. In HPHT synthetic diamonds the most common inclusions are relics of the nickel-iron-based flux used in the growth process, while in CVD it’s common to spot small black particles which differ from the similar ones found in natural diamonds. As the growth process keeps improving, though, it’s often rarer to find inclusions in synthetic diamonds and other techniques need to be used for their correct identification.
Elongated metallic flux inclusion found in HPHT created lab -grown/synthetic diamonds
Pricing
When it comes to the cost of lab-grown and natural diamonds, there is a significant difference between the two. When the synthetics started to appear consistently on the market their price was already from 15 to 40 percent less than natural ones. In a few years, due to the improvement of growing methods and the huge investments in countries like China and India, prices of synthetic are in free fall. We can say that, at the moment, the cost of synthetic rough is not much higher than one of its common simulants. What still keeps the price of the polished synthetic diamond far higher than cubic zirconia (CZ) or synthetic moissanite is the cutting process which, especially in small sizes exceeds by folds the price of the rough material.
Which should you buy?
When selecting the right diamond for you, the decision is ultimately yours. Before making your choice, though, consider the advantages and disadvantages of both lab-grown and natural diamonds.
Lab-grown diamonds offer a few advantages over natural diamonds. Likely one of the main reasons why they are preferred over the natural diamond is the certainty that they have not been mined by spoiling disadvantaged populations or are in some way connected with wars or illegal activities, they are, in a few words: ethical. The diamond industry has taken action against conflict diamonds; starting in 2000, they established an international initiative in an effort to eliminate the trade of conflict diamonds called the Kimberley Process. Other reasons can be the extremely low prices and even the availability of many different colors at prices comparable to the colorless ones.
Natural diamonds have their own set of benefits as well. Being the result of a unique geological process that occurred in a specific and unrepeatable timeframe of our planet's formation, their availability is limited. The conditions required for their formation in the deep earth mantle are unique too, besides the availability of carbon, very specific pressure and temperature are needed for an extended period to allow the formation of the crystals. Once formed then, these crystals had to be protected in some way by kimberlitic rock to arrive on the surface without burning. Natural diamonds are a miracle of nature.
Ultimately, choosing a lab-grown or natural diamond is up to you. Weigh the pros and cons of each before making your decision. Be sure to do your research and find a reliable source for whichever type of diamond you decide to purchase.