How Synthetic Diamonds Are Made

Natural diamonds are formed when carbon, exposed to high temperatures and pressures deep within the Earth for millions of years, transforms into diamond and is then rapidly pushed to the surface by tectonic movements, where it is mined. ‘Synthetic diamonds’ (synthetic diamond) are created by artificially replicating this formation process using high-pressure equipment to forcibly synthesize graphite into diamond. They are also known as ‘man-made diamonds’ (man-made diamond) or “lab-grown diamonds.”

Synthetic diamonds can be produced with crystal structures and physical properties nearly identical to those of natural diamonds, and some even possess superior characteristics in terms of hardness, thermal and electrical conductivity, and electron mobility compared to natural products. After all, because they can be supplied with consistent quality, synthetic diamonds have long been used for so-called “industrial applications” such as abrasives, cutting tools, and heat sinks. Furthermore, “synthetic” diamonds are being reevaluated from the perspective of issues such as conflict diamonds (a source of war funding) and child labor, which are particularly problematic in Africa. Additionally, technological innovations have made it possible to produce large stones—something previously considered difficult—leading to their growing presence in the jewelry market in recent years.

Here, we will introduce the principles behind the current mainstream methods of synthetic diamond manufacturing.

The specks of light visible in the cross-section are diamond particles. This lump is finely crushed and then dissolved and extracted using strong acid. It is then sorted by size and processed into finished products.