Synthetic diamond (also known as laboratory-created diamond, laboratory-grown diamond, cultured diamond or cultivated diamond) is diamond produced in an artificial process, as opposed to natural diamonds, which are created by geological processes. Synthetic diamond is also widely known as HPHT diamond or CVD diamond after the two common production methods (referring to the high-pressure high-temperature and chemical vapor deposition crystal formation methods, respectively). Although often referred to as synthetic, this term has been considered somewhat problematic.
The properties of synthetic diamond depend on the details of the manufacturing processes; however, some synthetic diamonds (whether formed by HPHT or CVD) have properties such as hardness, thermal conductivity and electron mobility that are superior to those of most naturally-formed diamonds. Synthetic diamond is widely used in abrasives, in cutting and polishing tools and in heat sinks.