India is the biggest consumer of Diamonds in the World. However, due to time consuming and intricate process for mining diamonds from Earth there is an associated high cost. Thus there is need for the option, like many developed countries, to develop diamonds in the Lab. India is also working on this sophisticated Lab diamond technology which scientist believe will be the new luxury.
Diamond Synthesis or preparing diamond in Lab is not new to the world. Many scientists have tried to synthesize diamond using approaches somewhat similar to high pressure, high temperature (HPHT) method during the later parts of 18th and early 19th Century.
Presently, USA, European Union, Russia, China, Japan, South Korea and Singapore have already developed various technologies and are producing lab diamonds. India,the biggest consumer of natural diamond, is still dependent on import and the concept of lab diamond is still unknown. Lab diamond is 15 to 20 per cent less expensive to the real natural diamond. Since the technology is intricate and demands rocket science level of attention for processing, it is still not in the reach of average consumer.
Several Labs in India are working on the preparation of diamond through Chemical Vapour Deposition (CVD) of carbon bearing molecules in plasma state. Currently CVD process is the preferred method due to lower cost of equipment, ease of operation, better quality of crystals and overall lower running costs of the process. All this is on research and development phase.
Acting Director,Dr. S.K. Mishra at CSIR Institute of Minerals and Materials Technology, Bhubaneswar, told UNI that CVD diamond is being pursued in several places such as in IMMT Bhubaneswar, CGCRI Kolkata, IIT-Madras Chennai, IIT Mumbai, BIT-Mesra Ranchi, and Technos Instruments Jaipur.
Currently only colored gemstone and gem identification work is ongoing in Western India. However, there is no gemstone processing work going as yet in India, he added.There are two different ways to make synthetic or Lab diamond. Thus diamonds can be made in laboratory either by HPHT or by CVD method.
Dr Mishra said, “At IMMT, we are able to make diamond coating (which consist of microscopic diamond crystals) in a microwave plasma CVD reactor. Although the process is quite complex.” He added that Gem grade diamond can be grown by the plasma CVD method using small seed crystals of diamond grown by HPHT method. The growth rate of diamond is quite slow so it takes about couple of weeks to get a millimetre size crystal! Diamond crystals with striking colour can be made by suitably doping boron, nitrogen and other elements or by introducing controlled amount of defects.
In 1954 GE (USA) scientists reported the formation of synthetic diamond by HPHT route by applying very high pressure (around 50,000 times atmospheric pressure and high temperature). However, growing large diamond crystals of interest for use as gems still require a complicated, very time and energy consuming process. For this reason, this process is very much prohibitive in cost and not practical.
Synthetic diamond seems to be the best future option but this will not displace the real diamond any time soon as there is not a larger cost different.