Differences between natural diamonds, lab-grown diamonds, and diamond simulants

Diamond simulants, including lab-grown diamonds, are seen everywhere these days.
This article explains the differences between them and how to tell them apart.

■Introduction to Natural Diamonds, Lab-Grown Diamonds, and Diamond Simulants

-Diamonds-
Diamonds are rare minerals that have formed in nature over tens of millions of years, and are crystals made of carbon atoms. They possess extremely high hardness and luster, and boast the highest value as gemstones. The price of diamonds varies greatly depending on their origin and rarity. Additionally, diamonds are often used as gifts, such as for engagement rings, and thus hold emotional value.

-Lab-Grown Diamonds-
Lab-grown diamonds are diamonds created artificially, possessing the same physical properties as natural diamonds. Lab-grown diamonds are created by artificially synthesizing diamonds under high temperature and high pressure. As a result, impurities present in natural diamonds are removed, producing high-quality diamonds of consistent quality. They are less expensive than natural diamonds and are an eco-friendly option.

-Cubic Zirconia-
Cubic zirconia is a crystal of zirconium oxide (a synthetic stone) created artificially from a substance not found in natural minerals. It has a luster similar to diamonds and a similar appearance, so it is sometimes used as a gemstone. However, it has lower hardness than diamonds and is more prone to scratches, thus lacking in durability. It is also very low in price and widely known as a diamond substitute.

-Moissanite-
Moissanite is a type of silicon carbide mineral that is extremely rare in nature, and natural moissanite is very difficult to find. Therefore, the moissanite seen in the market is a "synthetic stone" that has been artificially synthesized with the exact same chemical composition as the mineral.
It has an appearance very similar to diamonds and, like cubic zirconia, is used as a diamond substitute. Moissanite is characterized by its extremely high hardness, strong brilliance, and high refractive index. Furthermore, its specific gravity is lighter than diamonds, and its price is also lower than diamonds, making it an attractive option for those who want to obtain a high-quality gemstone at an affordable price.

■Chemical Properties of Diamond Simulants

※Hardness is Mohs hardness, and refractive index indicates actual measured values.

From the table above, it can be seen that diamonds and lab-grown diamonds have almost the same chemical properties, such as hardness, refractive index, and conductivity. From a chemical perspective, they can be said to be the same. On the other hand, cubic zirconia is characterized by a slightly lower hardness and a lower refractive index than diamonds. Moissanite, meanwhile, has a very similar appearance to diamonds and is characterized by its high hardness. Regarding thermal conductivity, moissanite is the highest, and cubic zirconia is the lowest.

■How to Identify Diamond Simulants

In conclusion, distinguishing between diamonds and lab-grown diamonds is extremely difficult, and most amateurs cannot tell the difference. Typically, lab-grown diamonds often have a more perfect shape than natural diamonds, and may not have minute internal characteristics. Also, because lab-grown diamonds are artificially created, larger sizes of diamonds can sometimes be obtained at a relatively lower price.

On the other hand, cubic zirconia and moissanite are characterized by their strong resemblance to diamonds. However, since their physical properties such as hardness and refractive index differ, expert appraisal by jewelers or gemologists is necessary. Furthermore, since moissanite is a relatively new material, it can be difficult for non-experts to distinguish.

As explained above, these materials are so similar that expert appraisal is required to distinguish them. Especially distinguishing between diamonds and lab-grown diamonds is very difficult, so consult a reliable gemologist.

■Summary

How was it? I hope this was helpful regarding diamonds, lab-grown diamonds, and diamond simulants.

Please check out our other articles for more detailed information on lab-grown diamonds!

Related Article
「Lab-Grown Diamonds VS Natural Diamonds: Which Will You Choose?」