The laboratory synthesis of diamonds
The laboratory synthesis of diamonds is the process of creating diamonds in controlled laboratory conditions. This process simulates the natural conditions under which diamonds form in the Earth’s crust, but it is much faster. There are various methods of synthesizing laboratory diamonds but the two most commonly used are Chemical Vapor Deposition (CVD) and the High Pressure High Temperature method (HPHT).
The CVD (Chemical Vapor Deposition) method
Chemical Vapor Deposition (CVD): This method involves introducing a suitable carbon-containing gas (such as methane) into a vacuum chamber where a substrate (often a metal plate or diamond crystal) is placed. The gas is then ionised or heated to produce active carbon atoms which deposit themselves on the surface of the substrate and form the crystal structure of the diamond.
The HPHT (High Pressure High Temperature) method
High Pressure High Temperature (HPHT) – this method simulates the conditions in the Earth’s crust where natural diamonds are formed. A carbon-containing base material (such as graphite or a diamond crystal) is placed in a high pressure and high temperature environment where the carbon atoms then arrange themselves into the crystal structure of a diamond. Both of these methods produce diamonds with similar physical and optical properties to natural diamonds. Laboratory synthesis of diamonds is key for the production of diamonds to be used in jewelry making, scientific research and industry.