The Different Types Of Lab Grown Diamonds An overview of CVD and HPHT.
What are Lab-Grown Diamonds? Lab-grown diamonds, also known as synthetic diamonds, man-made diamonds, or cultured diamonds, are diamonds produced in a laboratory setting using technological processes that mimic the natural diamond creation process. These diamonds consist of actual carbon atoms arranged in the characteristic diamond crystal structure. Due to their identical chemical composition and atomic structure, lab-grown diamonds possess the same optical, physical, and chemical properties as natural diamonds.
Two Primary Methods for Creating Lab-Grown Diamonds 1. Chemical Vapor Deposition (CVD)
2. High-Pressure/High-Temperature (HPHT)
CVD involves placing a diamond seed crystal in a vacuum chamber filled with carbon-containing gases like methane. The gases are heated to break down their molecular bonds, and the carbon atoms precipitate onto the seed crystal, gradually building up the diamond’s crystal lattice structure. CVD diamonds often require additional treatments, such as irradiation or annealing, to enhance their color.
HPHT replicates the conditions deep within the Earth where natural diamonds form. In this process, carbon materials are subjected to immense pressures (around 1.5 million pounds per square inch) and high temperatures (approximately 2,700 degrees Fahrenheit) in the presence of a metal catalyst. The carbon melts and then crystallizes around diamond seeds, forming larger diamonds.
Lab-Created Diamond Alternatives
It's important to distinguish lab-grown diamond from diamond simulants. These alternatives mimic the appearance of diamonds but do not possess the same chemical composition or properties. Cubic Zirconia (CZ): A synthetic gemstone made of zirconium dioxide. CZ is visually similar to diamonds but lacks their hardness and brilliance. Moissanite: A naturally occurring mineral (silicon carbide) that is also synthesized in laboratories. Moissanite is known for its exceptional sparkle and is more durable than CZ but still distinct from diamond. White Sapphire: A colorless variety of the mineral corundum. White sapphires are durable but lack the brilliance and fire of diamonds.
Conclusion Lab-grown diamonds offer an ethical, sustainable, and cost-effective alternative to mined diamonds. Understanding the different methods of creation, CVD and HPHT, as well as distinguishing them from diamond simulants like cubic zirconia, moissanite, and white sapphire, ensures informed choices for jewelry consumers. Source: articleted.com