How Are Lab Grown Diamonds Made?

You have many options when it comes to the type of gemstones to buy. While researching diamonds, you likely have come across information about problems within the mined diamond industry and are now considering lab grown diamonds.

Lab-grown, lab-created, human-made, ethically-grown, CVD: there are plenty of ways to describe diamonds that are created in labs, but there are two primary ways these clean alternatives to mined diamonds are made. Before exploring those two methods, it’s important to understand exactly what lab-grown diamonds are and how they compare to mined diamonds.

What Are Lab Grown Diamonds?

First and foremost, lab-grown diamonds are exactly what their name implies-they are real diamonds that are grown in a lab. These diamonds may be created by human technology, but the methods used are simply an accelerated process of those that happened inside the earth over millions of years. 

Like earth diamonds, clean lab diamonds are composed of pure carbon, crystallized into isotropic 3D forms. Lab-grown diamonds are identical chemically, structurally, and optically to earth-grown diamonds, but, without the associated problems of extracting them through mining. 

All diamonds, whether mined or created in a lab, are graded by the 4 Cs-cut, color, clarity, and carat-in gemological laboratories by diamond graders and gemologists. The high standards used by these labs ensure that your pure lab-created diamond is something you can be proud of. Each lab requires that several specialists individually grade each diamond. They analyze how each diamond was cut from its original shape; how flawless it is, inside and out; how clear the diamond is; and how much it weighs.

In addition to the ethical problems associated with diamond mining, lab diamonds differ from mined diamonds in their origin and their cost. Mined diamonds have to be wrested from deep inside the earth, or extracted from stream, river, and ocean beds, while lab-grown diamonds are created in controlled environments. The prices for mined diamonds can be up to 40% more expensive than lab-grown, but average about 30% higher. All-in-all, buying lab-grown diamonds is both more affordable and socially conscious than purchasing mined diamonds.

What Methods Are Used To Create Lab Diamonds?

Inventors and chemists first attempted to recreate earth diamonds as early as the 1800s, mostly for industrial purposes. Because they rate as the hardest materials on the Mohs Scale, diamonds have been used in industry for many years to cut, polish, and grind other products. Creating diamonds was thought to be a better, less expensive alternative to mining them. Diamonds would finally be successfully grown in independent labs in the 1950s, by both General Electric and the Swedish company, ASEA. The first gem-quality stones were grown by GE in 1970, although the pure quality we know today took years to perfect.

The two main methods used to create diamonds are referred to by their initials: HPHT and CVD. The original method, High Pressure High Temperature (HPHT), is widely used due to its relatively low costs. The preferred method of most lab grown diamond jewelers is the Chemical Vapor Deposition (CVD) method.

HPHT involves the use of powerful presses, either the belt press, the cubic press, or the split-sphere (BARS) press, combined with heat in excess of 1400 degrees Centigrade. A diamond seed is placed in the press, then heated until a solvent metal dissolves a pure carbon source (like graphite), which attaches to the diamond seed and crystallizes into a diamond gem. Most diamonds made with HPHT are in the one to one and a half carat range. Because of the smaller sizes and the lower production costs, HPHT diamonds are more suitable for industrial applications.

The second method, CVD, is the preferred method for gem-quality diamonds. Chemical Vapor Deposition (CVD), creates a diamond crystal from a hydrocarbon gas mixture. First a substrate that has been cleaned with diamond powder is placed into a chamber; the chamber is filled with carbon (usually methane) and hydrogen gases, then heated to about 800 degrees Celsius. The process allows the carbon atoms to bond with the substrate and build over time into a pure carbon crystal that grows into a raw diamond. Hydrogen is important to the process, as it selectively etches off any non-diamond carbon from the growing crystal. 

There are important benefits to using the CVD method. First, diamonds can be grown over large areas, allowing more and larger diamonds to be grown at the same time. Impurities within the crystals can be better controlled, allowing for higher quality diamonds. And finally, unlike HPHT, the CVD method does not require high pressures or as intense heat, so less energy is required to produce fine diamonds.

The Clearest Choice

Lab grown diamonds provide the diamond jewelry industry a clean beginning. By offering diamonds free from the issues surrounding diamond mining, lab diamonds allow you to make purchases based on your high standards and principles. You now have more choices than ever before: whether it's what food to put into your body, which health and beauty products to use, or what type of diamond to put into your fine jewelry. With technology intersecting luxury, you now have the clearest choice in lab grown diamonds.