Chemically, physically, and optically, lab-grown diamonds are identical to natural ones. They’re real diamonds with the same crystal structure and beautiful sparkle as natural diamonds. Lab-grown diamonds also have the same famous Mohs hardness of 10. They’re just as durable as natural diamonds, but they’re a bit easier on your pocketbook.

At first glance, there’s no way to tell the difference between a lab-made diamond and a natural one. However, there are two small details you could look for.

With a magnifying glass, try to find a tiny laser inscription on the girdle — the widest part of the diamond that forms its outline when you look at it from the top. See if you can read it. Many lab-made diamonds have an inscription that identifies them as lab-made.

Diamonds can also have a lab report number inscribed on the girdle. If you go to the laboratory website, you can enter this number to get the report, which will tell you whether the stone is mined or lab-grown, along with plenty of other information.

If there’s nothing on the girdle, only a major gemological laboratory can tell you whether the diamond is mined or created.

Lab-made diamonds have the same thermal and electrical conductivity as mined diamonds. So, they will pass a diamond tester exam.

Since a lab-grown diamond appears identical to a mined diamond, most jewelers won’t be able to tell the difference. (Assuming, of course, that the diamond has no girdle inscriptions). However, jewelers who are also trained gemologists may be able to tell whether a diamond is lab-grown with the aid of a powerful microscope. Still, the only way to be certain is to send it to a gemological laboratory.

Lab-made diamonds have the same thermal and electrical conductivity as mined diamonds. So, they will pass a diamond tester exam.

Two processes can create jewelry-quality diamonds: HPHT and CVD.

HPHT stands for High Pressure/High Temperature. This process mimics the way that diamonds grow in nature, subjecting carbon to high temperatures and pressing it together. This costly method requires a lot of energy.

CVD stands for Chemical Vapor Deposition, and it’s not as scary as it sounds. In this process, a mixture of hydrogen and methane gas is placed in a chamber with a seed crystal. Typically, microwave power heats the chamber to a high temperature, which excites the gas. The diamond grows on the seed crystal. The CVD method is cheaper than HPHT and has become more common in recent years, as new technology has made higher-quality diamonds possible.

Lab-made diamonds typically have good clarity. Like a high-quality natural diamond, lab-made diamonds won’t get cloudy.

Ethical diamond mining has become a hot topic, and the easiest way to avoid unethically mined diamonds is to choose a lab-made one. Diamonds grown in a lab are never “blood diamonds” and have a smaller environmental footprint than mined diamonds. That makes lab-made diamonds a more environmentally sustainable option, too. Still, there are ways to purchase ethically mined diamonds. Diamond mines in Canada, Botswana, and Australia have opted for a more transparent supply chain. You can also shop for a “recycled,” secondhand diamond.

As long as they have a nice cut, lab-grown diamonds will sparkle!/p>