What is a Lab-Grown Diamond?

Lab-grown diamonds, also known as lab-created, man-made, engineered, or cultured diamonds, are produced in controlled laboratory settings that replicate the natural conditions under which diamonds form in the Earth’s mantle. These diamonds are made of carbon atoms arranged in the same crystal structure as natural diamonds, giving them identical optical and chemical properties.

How Are Lab-Grown Diamonds Made?

Lab-grown diamonds start with tiny carbon seeds from existing diamonds. Scientists use advanced techniques to simulate the natural diamond formation process. This involves either:

  1. High Pressure High Temperature (HPHT): This method replicates the intense conditions found deep within the Earth. Carbon material is subjected to extreme pressure (over 870,000 lbs. per square inch) and high temperatures (1300 – 1600 degrees Celsius) in a large machine to create a rough diamond. After formation, the diamond is cut, polished, and set into jewellery like earrings, necklaces, or bracelets.

  2. Chemical Vapor Deposition (CVD): In this process, a seed diamond is placed in a vacuum chamber filled with heated hydrogen and carbon gases. The gases break down, allowing layers of carbon to crystallise around the seed, gradually forming a diamond. Some CVD diamonds might also undergo additional pressure and heat treatment after growth.

Distinguishing between natural diamonds and lab-grown diamonds, whether made using the HPHT or CVD method, is not possible with the naked eye. Only specialised equipment can detect the differences, which are due to the specific conditions under which the diamonds were created.

Lab-Grown Diamonds vs. Natural Diamonds

Visually, lab-grown and natural diamonds are indistinguishable—they both exhibit the same fire, scintillation, and sparkle. The key difference lies in their origin: one is formed naturally deep within the Earth, while the other is grown in a lab. Lab-grown diamonds may have different trace elements compared to natural diamonds, but these do not affect their appearance. Only with specialised testing can lab-grown diamonds be differentiated from natural ones.