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Diamonds are made from highly organized carbon. Natural Diamonds take around 1 billion to 3 billion years to form. Lab Grown Diamonds are created by applying heat and pressure to a diamond seed. This chamber replicates the conditions which are present inside the earth’s surface. The diamonds take around six to eight weeks to form. The diamonds are then cut, polished and graded. It is virtually impossible for the naked eye to tell the difference between lab grown and mined diamonds. They are a revolution in the diamond industry. Lab Created Diamonds many advantages over mined diamonds.<br>
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Introduction • Diamonds are made from highly organized carbon. Natural Diamonds take around 1 billion to 3 billion years to form. Lab Grown Diamonds are created by applying heat and pressure to a diamond seed. This chamber replicates the conditions which are present inside the earth’s surface. The diamonds take around six to eight weeks to form. The diamonds are then cut, polished and graded. It is virtually impossible for the naked eye to tell the difference between lab grown and mined diamonds. They are a revolution in the diamond industry. Lab Created Diamonds many advantages over mined diamonds.
Chemical Vapour Deposition (CVD):- • CVD Process is used to create gem quality diamonds.CVD process uses ultra pure rich carbon gases in a controlled environment/chamber. • Some CVD Processes are mentioned below:- • Low-pressure CVD (LPCVD) • Ultrahigh vacuum CVD (UHVCVD) • Plasma-enhanced chemical vapour deposition (PECVD) • Microwave Plasma Vapour Deposition (MPCVD)
High Pressure High Temperature:- • In HPHT the machines have the ability to boils up the pressure of almost 60,000 atmospheres and temperature of 2,500°C.It contains all the elements that are needed to grow a diamond. It includes a tiny diamond seed, highly refined graphite and a catalyst mixture containing metals and powders. The catalyst inside react to added heat and pressure resulting in molten form. • The molten catalyst solution causes the graphite (carbon) to dissolve. After this the cooling process takes place. It requires a controlled environment to produce a gem quality diamond.
Two main press designs are used to supply required temperature and pressure.
Belt Press:- • High Pressure is created by using two high strength pistons which provide equal pressure in opposing directions.
Cubic Press:- • This technique uses many pistons that provide pressure from many different directions.