Lab-grown diamonds are produced in a synthetic environment that replicates the natural diamond formation process beneath the Earth's mantle. Two methods are utilised for producing lab-grown diamonds, namely CVD (chemical vapor deposition) and HPHT (high pressure high temperature). Both methods are efficient in generating high-quality, genuine diamonds that are indistinguishable from naturally occurring ones.

The process of creating CVD diamonds involves using atomic hydrogen to transform graphite into diamonds. In nature, hydrogen is commonly found in the form of hydrogen molecules, which consist of two hydrogen atoms bonded together.

To produce CVD diamonds, the first step is to dissociate molecular hydrogen into atomic hydrogen. This can be achieved by utilising a gas activation agent such as an intense plasma or a hot filament.

Once the hydrogen gas is dissociated into its atoms, it is carefully applied to the substrate, which is typically graphite. The hydrogen selectively erodes the graphite surface and breaks its double bonds, causing the graphite bonds to be converted into diamond bonds.

The process begins by placing a thin seed diamond in a sealed chamber and heating it to high temperatures, generally around 800 degrees Celsius. Subsequently, hydrogen or a mixture of carbon-rich gases that includes hydrogen and methane is introduced into the chamber. By applying the methods mentioned above, the gases become ionised and their molecular bonds are broken. This results in the deposition of pure carbon onto the diamond seed, and as additional carbon atoms are formed, they form atomic bonds that are identical to those of diamonds.

Creating an HPHT lab diamond involves a series of steps that require expertise, precision, and specialised equipment. HPHT is a process in which pure carbon is subjected to intense heat and pressure within a metal cube by using electric pulses. The carbon eventually breaks down and crystallises into a diamond. Any metal residues within an HPHT diamond are usually microscopic and not easily visible.

According to most experts, HPHT diamonds are of higher quality than CVD diamonds. CVD diamonds are produced quickly, which can result in internal marks and graining. Additionally, CVD diamonds often have a brownish hue, necessitating post-growth treatment to enhance their appearance. HPHT diamonds are generally produced to a higher standard and do not require post-growth treatment.

Similar to natural diamonds, lab diamonds undergo rigorous grading evaluations during certification by grading organisations such as GIA and IGI. Therefore, you can filter your diamond search based on the usual cut, colour, and clarity standards to find a lab diamond that is equally beautiful as a top-quality natural diamond.