A diamond, incarcerated in its subterraneous prison, rough and unpolished, differs not from a common stone
Charles Caleb Colton
Synthetic diamonds that are commercially sold are mostly yellow in color and made from a process known as High Pressure High Temperature (HPHT). The yellow color present in many is produced by nitrogen impurities. Yellow is not the only color that might be present. Other synthetic stones may produce shades of blue, green or pink that result from additions such as boron or because of irradiation.
Some synthetic diamonds are used as cheaper versions of the more expensive naturally formed diamonds. Traditionally the demand for industrial diamonds (the so-called "ugly" type of diamond, used for construction purposes) has been satisfied with synthetic diamonds. Because of the many gemological as well as industrial uses of diamonds, there has been a large demand for rough stones.
The diamond cutting process involves several steps. These stages of gem development include planning, cleaving or sawing, bruting, polishing, and final inspection. Here is a closer look and a definition of what those steps all mean. Cleaving or sawing – Cleaving is the separation of a piece of diamond rough into separate pieces, to be finished as separate gems. Sawing is the use of a diamond saw or laser to cut the diamond rough into separate pieces. Bruting - the process whereby two diamonds are set onto spinning axles turning in opposite directions, which are then set to grind against each other to shape each diamond into a round shape. This can also be known as girdling. Polishing - the name given to process whereby the facets are cut onto the diamond and final polishing is performed. This step gives the diamond its brilliant sparkle that we know so well. Final inspection – the final stage of diamond cutting involves thoroughly cleaning the diamond in acids, and examining the diamond to see whether it meets the quality standards of the manufacturer.